®!|E ^. ^. ^tU ICtbravg ^ort{| darolma ^tate College 'NrjNESiUNG NORTH CAROLINA STATE UNIVERSITY LIBRARIES III nil: jjiiiiiiiji 11.11 ;iiiiiiiii in S01950166 S THIS BOOK IS DUE ON THE DATE INDICATED BELOW AND IS SUB- JECT TO AN OVERDUE FINE AS POSTED AT THE CIRCULATION DESK. APR -9 1986 100M/7-85 f07 W\ THE FEEDING OF DAIRY CATTLE BY ANDREW C. McCANDLISH, M.S. A. Professor of Dairy Husbandry, Iowa Stale College of Agricullure and Mechanic Arts NEW YORK JOHN WILEY & SONS, Inc. London: CHAPMAN & HALL, Limited 1922 Copyright, 1922 By ANDREW C. McCANDLISH PRESS OF BRAUNWORTH & CO. BOOK MANUFACTURERS BROOKLYN, N. Y. Imp. Jewel's Guernsey Lily DEDICATED TH1-: COW WITH THE CRUMPLED HORN V^ P> 1730^ PREFACE The art and science of feeding dairy cattle has ever been changing, and during the last two decades greater improve- ments have been brought about in this branch of agriculture, by practical feeders and investigators, than ever before. The importance of the dairy cow as an economic factor is now recognized. This is primarily due to the fact that, with little waste of energy, she converts the roughages and other feeds grown on the farm into products suitable for human consumption. In making this presentation of the feeding problem the aim has been to render the work broad enough to be of aid to the student. For this purpose the earlier sections contain a brief resume of material which belongs to the field of nutri- tion rather than to that of feeding. It is hoped that this will render it possible for the student to link up his work on feeding dairy cattle with the training he has previously received in nutrition. At the same time it is hoped that the man interested in feeding, but with little foundation in nutrition, may obtain some information of value from the earlier part of the work. To put it briefly, the main object in view has been to review, in a non-technical manner, the main principles on which the feeding of dairy cattle is founded and then discuss the problems of practical feeding. Much of the technical information included has been ob- tained from Government and State Experiment Station Vlll PREFACE publications, but as this is not intended to be a reference work, direct mention of these could not always be made. The remaining material consists of information obtained in the practical management of a herd and from many feeders, as well as from experience gained while connected with the practical and investigational work of the Dairy Husbandry Department of Iowa State College, during the past eight years. All of the illustrations are taken from the Iowa State College herd, and the writer wishes to express his thanks to Dean C. F. Curtiss for permission to use these. The author also wishes to express his appreciation of the advice received from Professor H. H. Kildee; of the excellent suggestions received from Professor E. Weaver, who read the manuscript; and of the valuable editorial aid given by Professor F. W. Beckman. Andrew C. McCandlish. Iowa State College, Ames, Iowa. September, 19 21 CONTENTS PART I THE FUNDAMENTAL PRINCIPLES OF DAIRYING CHAPTER PAGE I. The Individual Cow as the Unit in Profitable Dairying. ... 3 Breeding 3 Selection 7 II. The Importance of Feeding 15 Liberal Feeding Essential 15 Beginning with the Young Stock 18 Necessity of Individual Feeding 19 PART II THE CHEMISTRY OF FEEDING III. The Elementary Composition of Feeds 25 Carbon 25 Hj'drogen 26 Oxj'gen 26 Nitrogen 27 Potassium 27 Sodium 27 Calcium 28 Magnesium 28 Iron 28 Sulphur 28 Phosphorus 28 Iodine 29 Chlorine 29 Fluorine 29 Silicon 30 ix CONTENTS CHAPTER PACE IV. The Constituents of Feeds 31 Water 32 Carbohydrates 32 Crude Fiber 32 Nitrogen-free Extract 32 F^ts ^^ Proteins 33 Non-protein Nitrogenous Compounds 34 Vitamines 34 Pigments 35 Ash 35 V. Digestion and Absorption 36 The Mouth 37 The Stomach 38 Rumen 39 Reticulum 40 Omasum 41 Abomasum 41 The Intestine 42 Small Intestine 42 Large Intestine 45 VI. The Utilization of Nutrients 46 The Body Activities 46 Maintenance 46 Fattening 47 Growth 47 Fetal Development 48 Milk Production Comparison of the Nutrients 49 Digestibility 49 Digestible Carbohydrate Equivalent 49 \ Total Digestible Nutrients 49 Nutritive Ratio 50 Energy Values 50 Functions of the Nutrients 52 Water 52 Carbohydrates 52 Fats 53 Proteins 53 Non-protein Nitrogenous Compounds : . . 53 Vitamines 54 Pigments 56 Ash 58 CONTENTS CHAPTER PAGE VII. The Influence of Nutrition on Production 60 Individual Nutrients 60 Water 60 Carbohydrates 60 Fats 61 Proteins 61 Amount of Protein 61 Nature of Protein 62 Non-protein Nitrogenous Compounds 63 Vitamines 63 Pigments 63 Ash 63 Plane of Nutrition 63 Overfeeding 63 Underfeeding 64 FART III THE REQUIREMENTS OE THE ANIMAL VIII. Feeding Standards 69 Development 69 Criticisms 72 Standards Based on Gross Weight 72 Standards Based on Total Nutrients 73 Standards 'Based on Digestible Nutrients 73 Standards Based on Energy Values 75 A Suitable Standard 76 Formulating Rations 77 IX. The Balance of Nutrients 81 ^ge 83 Size 83 Condition 84 Yield of Milk 85 Quality of Milk 85 Stage of Lactation 86 Individuality of the Cow 86 X. Characteristics of a Good Ration 88 Palatability 88 Variety ^2 Bulk 94 Succulence 06 Effect upon the Sj-stem q6 Efifect upon the Products 97 CONTEXTS PART IV THE FEEDING STUFFS CHAPTER PAGE XI. Silage loi i/^ Corn Silage loi cX Other Silage Crops io8 Non-leguminous io8 Leguminous 109 Mixed 1 10 XII. Soiling Crops in Leguminous in Alfalfa Ill Clovers 112 Sweet Clover 113 Peas 1 13 Vetches 114 Cowpeas 1 14 Soybeans > 114 Non-leguminous 115 Corn 115 Sweet Com 115 Lesser Cereals 115 Millets 116 Sudan Grass 117 Amber Cane 117 Other Sorghums 118 Grasses 118 Rape 1 19 Mixed 119 Pea Mixtures 119 Vetch Mixtures 120 Cowpea JMixtures 1 20 Soybean Mixtures 1 20 XIII. Miscellaneous Succulent Roughages 121 Pasture 121 Root Crops 124 Beet Pulp 125 Potatoes 1 26 Pumpkins 127 ^ XIV. Dry Roughages 128 Leguminous 128 Alfalfa Hay 129 CONTENTS xiii CHAPTER PAGE Clover Hays 130 Sweet-clover Hay 131 Field-pea Hay 131 Cowpea Hay 131 Soybean Hay 132 Leguminous Straws 132 Non-leguminous 132 Corn Fodder 133 Corn Stover. 133 Cereal Straws 133 Timothy Hay 133 Sudan-grass Hay 133 The Sorghums 133 The Millets 134 Buckwheat Straw 134 Flax Straw Mixed. 134 135 Mixed Hay 135 Oat and Pea Hay 135 XV. The Cereal Grains and Their By-products 136 Corn and Its by-products 136 Corn Preparations 138 Ear Corn 1 39 Shelled Corn 139 Cracked Corn. C39 Corn Meal 139 Corn-and-cob Meal 140 Com By-products 140 Hominy Feed 140 Germ-oil Meal 141 Corn Bran 141 Gluten Meal 141 Gluten Feed 142 Corn Distillers' Grains 142 Oats and Their By-products 142 Oats 143 Oat By-products 143 Wheat and Its By-products 143 Wheat 144 Wheat Bran 144 Wheat Middlings 144 Flour-wheat Middlings 145 Red Dog Flour 145 V CONTENTS A.PTER PAGE Barley and Its By-Products 145 Barley 145 Barley Bran and Barley Shorts 146 Malt Sprouts 146 Brewers' Grains 146 Rye and Its By-products 147 Rice and Its By-products 147 The Sorghums 148 The Millets 149 XVI. The Legumes, the Oil Seeds, and Their Bv-PRODrrTS. . . . 150 Peas 1 50 Cowpeas 151 Beans 151 Soybeans 151 Peanuts 152 Cottonseed and Its By-products 153 Cottonseed 1 54 Cottonseed Hulls 155 Cottonseed Meal 155 Cottonseed Feed 1 56 Cold-pressed Cottonseed Cake 156 Flaxseed and Its By-products 157 Flaxseed 157 Linseed-oil Meal 157 Coconut Meal 159 Palmnut Meal 1 59 XVII. Miscellaneous Concentrates 160 Buckwheat and Its By-products 160 Molasses 1 60 Dairy Products 161 Whole Milk 161 Skim Milk 162 Buttermilk 162 Whey 162 Dried Dairy Products 162 Packing-house By-products 163 Tankage 1 63 Blood Meal 1 63 Fishery By-products 163 Fish Meal 163 Whale Meal 164 Proprietary Feeds 164 Standard Feeds 164 CONTENTS PAGE Mixed Concentrates 164 Alfalfa-molasses Feeds 165 Peat-molasses Feeds 1 6 5 Fillers 167 Tonic Feeds j68 PART V FEEDING PRACTICE 171 XIX. Summer Milk Production i^p XVIII. General Feeding Consideration XX. Silage versus Soilage ' jg2 Advantages of Silage 182 Feeding Economy 182 Labor-saving ^82 Feed Reserve 83 Disadvantages of Silage 18^ Lack of Variety 18^ Necessity of Small Silo 184 Advantages of Soilage 184 Intensity of Production 184 Small Initial Outlay 185 Variety in the Ration 186 Disadvantages of Soilage 186 Labor Requirements j86 Succession of Succulence 187 Silage or Soilage j88 The Soiling Problem jgj Production of Soiling Crops igi Feeding of Soiling Crops 1^2 Practical Soiling .Systems 1Q4 XXI. Winter Milk Production jg5 200 XXII. Preparation of the Cow for Production. The Dry Cow 200 The Cow Immediately before Parturition 201 The Cow Immediately after Parturition 203 XXIII. Feeding for Records 20c Fitting 20s Short-time Tests 205 Long-time Tests 207 Feeding During Record Period 208 XVI CONTENTS CHAPTER PAGE Short-time Tests 208 Long-time Tests 210 Feeding for a High Fat Percentage 210 XXIV. Calf-raising 212 Early Treatment 212 Teaching to Drink 213 Fundamental Principles in Hand-feeding 214 Whole-milk Period 215 Skim-milk Period 216 Use of Other Dairy By-products 216 Buttermilk 216 Whey 216 Dried Products 217 Milk Supplements and Substitutes 217 Miscellaneous Feeds 218 Grain 218 Hay 221 Silage 223^ ^ Roots 223 Pasture 223 Water 224 Salt 224 Condiments 224 XXV. Feeding Dry Stock 225 The Growing Heifer 225 Bulls 227 XXVI. Feeding for Show and Sale 229 Early Preparation 230 Final Fitting 231 XXVII. Water and Salt 233 Water 233 Salt 235 XXVIII. Feeding Methods 237 Order of Feeding 237 Feeding of Roughages 238^ Feeding of Concentrates 238 L^ Preparation of Feeds 240 Grinding 24c Chopping 241 Soaking 241 Cooking 242 XXIX. Feeding Economy 243 Individual Feeding 243 CONTENTS CHAPTER PAGE Liberal Feeding 245 Use of Home-grown Feeds 246 The Protein Supply 247 Choice of Protein Supplements 247 XXX. Digestive Disturbances 250 Calves 250 Constipation 251 Indigestion 251 Bloat. 251 Common Scours 252 Mature Stock 253 Indigestion 253 Bloat. 253 Impaction 256 PART VI APPENDICES I. Digestible Nutrients in Feeds 259 II. A Feeding Standard for Dairy Cows 263 III. Mineral Elements in Feeds 265 rV. Relative Economy of Protein Supplements 267 LIST OF ILLUSTRATIONS Dairy Herd and Barns at Iowa State College Frontispiece Imp. Jewel's Guernsey Lily Dedication FIG. PAGE I. Scrub Cow No. 60 5 II. Half-blood Holstein Cow No. 207 Out of Scrub No. 60 5 III. Three-quarter-blood Holstein Cow No. 311 Out of Half-blood Holstein No. 207 6 IV. Scrub Cow No. 53 8 V. Half-blood Guernsey Cow No. 180 Out of Scrub No. 53 9 VI. Half-blood Guernsey Cow No. 253 Out of Scrub No. 53 9 VII. Scrub Cow No. 6 on Arrival at Iowa State College 16 VIII. Scrub Cow No. 6 Three Years Later 16 IX. A Good, Well-shaded Pasture is One of the Greatest Assets of a Dairy Farm 1 23 X. Robinhood Cavalier Lass, Showing Condition Desired at the Beginning of a Lactation Period 202 XL Miss of St. Louis II, in Good Working Condition when the Lacta- tion is Well Started 204 XII. The Foundation of Production 213 XIII. lowana Mercedes Homestead in Working Condition 227 PART I THE FUNDAMENTAL PRINCIPLES OF DAIRYING THE FEEDING OF DAIRY CATTLE CHAPTER I THE INDIVIDUAL COW AS THE UNIT IN PROFIT- ABLE DAIRYING A STUDY of any herd of cows, unless they have been very carefully selected, will show that in addition to wide dififer- ences in conformational characteristics there are large indi- vidual variations not only in total milk and butter fat production but also in economy of production. The aim of the dairyman is to obtain a herd of cows combining con- formational excellence with economical production and, as the causes of the large individual variations which occur in production are fundamental, they must be given consideration before the feeding problem can be studied in a satisfactory BREEDING It is frequently stated that the breeding of a cow is very largely responsible for her inherent ability to produce milk and butterfat. That this is true to a very considerable degree has been shown in a breeding experiment at Iowa State 4 THE INDRIDUAL COW AS A UXIT College. Scrub cows of no known breeding and of very low producing ability were mated to pure-bred bulls of the Guernsey, Holstein and Jersey breeds and each heifer resulting from such a mating was bred back to a bull of the same breed as her sire. Records are now available on two genera- tions of grades descended from the original scrub cows of the experiment and it has been found that the first gen- eration grades produced on the average 39 per cent more milk and 38 per cent more fat than their scrub dams, while the increases in the case of the second generation grades, as compared with the scrubs, was 117 per cent in milk and 105 per cent in butter fat. This shows the influence breeding has on production, and demonstrates that the use of good bulls can do much to increase production, as the yield of butter fat was raised from an average of 185.18 pounds per year in the case of the scrubs to 379.31 pounds per year in the case of the second generation of grades. TABLE I Average Production of Two Generations of Grades and Their Scrub Ancestors Dams Daughters Grand-daughters Group Milk, Pounds Fat, Pounds Milk, Pounds Fat, Pounds Milk, Pounds Fat, Pounds Holstein 3673-8 4158.6 4046 . 7 167.36 190.77 193-91 6697-3 4786.4 4933-4 277.27 237.22 265.88 10,209.2 7,426.7 5.659-4 398.63 380.16 298.94 Guernsey Jersey Average 3912-3 185,18 5492.5 266.69 8,507.0 379-31 Fig. I. — Scrub Cow No. 60, Average Production 3313.2 Pounds of Milk and 178.47 Pounds of Fat. Fig. II.— Half-blood Hol>uiii (m., X, . : .7 Oui n\ .>, lub Xu. Oo. Average Production 6306.2 Pounds of Milk and 2S7.74 Pounds of Fat. THE IXDIMDUAL COW AS A UMT Fig. III.— Three-quarter-blood Holstein Cow No. 311, Out of Half-blood Holstein No. 207. Average Production 10,428.3 Pounds of Milk and 460.73 Poiuids of Fut. TABLE II Average Increase in Production of Two Generations of Grades Over Their Scrub Ancestors Increase in Production 0\t=r Scrub Ancestors Group First Generation Second Generation Milk, Per Cent Fat, Per Cent Milk, Per Cent Fat, Per Cent Guernsey Holstein 15 82 22 24 65 37 79 178 40 99 138 54 Jersey Average .... 40 44 117 105 SELECTION 7 Since breeding is an important factor in determining pro- duction, great care must be taken in the selection of breeding herds, and this is especially true in the case of the bulls to be used. No herd of cows should be headed by anything but a pure-bred bull, and some pure-bred bulls are not good enough to head even a scrub herd. TABLE in A Comparison of Two Guernsey Bulls Bulls Average Records of Dams Average Records of Daughters Increase in Production Over Dams Milk, Pounds Fat, Pounds Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent "Fullwood Hopeful" . . . Imp. Rouge II's Son. . . . 3885.2 4295 -6 169.99 194 05 4045 • I 5360.1 172.58 275.81 4 25 2 43 The two pure-bred Guernsey buhs, "Fullwood Hopeful" and Imp. Rouge II's Son, were used in the breeding work just mentioned, and although they were both of excellent breeding the results they produced were very different. The daughters of "Fullwood Hopeful" produced only 4 per cent more milk and 2 per cent more butter fat than their dams, so that this bull can be considered useless; while Imp. Rouge II's Son sired heifers producing on the average 25 per cent more milk and 43 per cent more fat than their dams. This emphasizes the importance of care in the selection of a herd sire. SELECTION Though breeding has a profound influence on production, it must be remembered that even when the ancestry of a cow is definitely known her ability to produce milk and butter fat 8 THE IXDmDUAL COW AS A UNIT cannot be accurately foretold. This is very clearly demon- strated by the case of two grade Guernsey cows in the Iowa State College experimental herd. These cows were sired by the pure-bred Guernsey bull, Imp. Rouge II's Son, and were out of a scrub cow of no known breeding. Fig. IV. — Scrub Cow No. 53. Average Production 5258.7 Pounds of Milk and 233.63 Pounds of Fat. Table IV Production of a Scrub Cow and Her Two Gr.-vde Daughters Cow A\-ERAGE Production Increase in Production 0\ER Dam Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent Scrub Xo ^ 7. 5258.9 3639.0 6128.4 233.69 180.53 298.33 -31 17 Grade No. 180 Grade No. 253 -23 28 SELECTION Fig. V. — Half-blood Guernsey Cow No. i8o, Out of Scrub No. 53. Average Production 3641.5 Pounds of IVIilk and 180.53 Pounds of Fat. Fic. \1.— Half-blood (iurrn.i >■ (',,•,,- Xm. 25;,, Out of Scrub X-. 5,-; and Full Sister to Half-blood Guernsey No. 180. Average Production 6168.2 Pounds of Milk and 306.40 Pounds of Fat. 10 THE TXDTMDrAT, C(^\V AS A l-XIT The two animals, Xo. iSo and No. 25^^, though full sisters, varied widely in producing ability, Xo. 180 producing 31 per cent less milk and 23 per cent less fat than her scrub dam, while No. 253 produced 17 per cent more milk and 28 per cent more fat than did her dam. This is a wide variation in production and might be attributed to the fact that the dam of the cows being considered w-as a scrub and consequently would tend to produce daughters of doubtful producing ability. It is true that the results obtained in the mating of scrubs are more doubtful and vary more than those obtained where pure breds which have been carefully selected for generations are concerned; but similar results are obtained, though less frequently, with pure-bred animals. TABLE V PROOrCTIOX OF A Px-RE-BRF.D GUKRXSKY CoW AXD HeR DAUGHTERS Cow No. A\ER.\GE PrODUCTIOX IXCREASE IX PrODUCTIOX 0\-ER Dam Milk, Pounds Fat, Pounds Milk. Per Cent Fat, Per Cent 98 225 267 7258.7 6213.0 0772.8 294.87 294.16 473.38 -14 35 61 Here the same wide difference in producing ability between the two pure-bred cows, Nos. 225 and 267, even though the\ were full sisters sired by Imp. Rouge II's Son, is noticed as was found in the case of the grades. But this might be attributed to the bull used; another pure-bred bull may there- fore be considered. SELECTION 11 He is the Jersey bull, Pogis 8oth of Hood Farm, and he sired two heifers out of a pure-bred Jersey cow, No. 127 in the Iowa State College herd. TABLE VI Production of a Pure-bred Jersey Cow and Her Daitohters Cow No. Average Production Increase in Production Over Dam Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent 127 194 223 8190.5 3345-3 7837 -ft 382.92 175.68 419.89 -59 — 4 -54 10 Here it is seen that in one case the production of the heifer was above that of her dam, while in the other case there was a very marked difference, and in both cases the milk yield for the heifers was lower than for their dam. This clearly shows that there are wide individual differences in the pro- ducing abiUty of animals of the same breeding. Where a consistent system of breeding has been pursued for some time the chances of a decrease in production with each succeeding generation are less, but at the same time it should be remembered that when a high level of production has been reached in a herd it is more difficult to increase the average production than it is in the case of a poor herd. Rigid selection of the sires is needed in such cases, as is clearly demonstrated by a comparison of two Jersey bulls used at Iowa State College. Fox's Lad o' Dreamwold was a detriment to the herd, as his daughters produced 18 per cent less fat than their dams, 12 THE INDIVIDUAL COW AS A UNIT while Pogis 8oth of Hood Farm increased the average pro- duction of the herd by 12 per cent m fat yield. TABLE vn Comparison of Pure-bred Dauchters of Two Jersey Bulls Bulls Average Production OF Dams Average Production OF Daughters Increase m Production 0\T,R Dams Milk, Pounds Fat, Pounds Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent Fox's Lad o' Dreamwold. Pogis 80th of Hood Farm 7667.9 7280.4 356.30 343-25 6005.0 7300.2 200 . 84 385-92 — 22 -18 12 In breeding, and especially in the case of pure-bred animals, the problem of "nicking" must be given consideration. Some animals, even when capable of producing good offspring, will not give good results even when mated with individuals that are also good. This is most frequently found in the case of pure breds of dissimilar breeding, while good animals of similar breeding will generally "nick" well and give good results. This lesson can again be clearly shown from the breeding record of the Guernsey bull, Imp. Rouge II's Son. In stud}- ing these records it is found that Imp. Rouge II's Son was mated to two cows with average records below three hundred pounds of fat per year and three cows with an average production over this amount. It is found that the daughters of the high-producing cows were in every case poorer pro- ducers than their dams, and at first sight this might con- demn the bull as being unfit to mate with cows of this producing ability. However, when the other individuals SELECTION 13 are studied it is evident that the daughters of the poor pro- ducers were not only better than their dams but also better than either the daughters of the good producers or the good producers themselves. From this it is evident that the bull under consideration "nicked" well with some of the cows but did not "nick" with the others. In selecting a breeding herd it is difficult to tell whether or not the sire desired will "nick" with the foundation cows; however, attention to the results that have been obtained with animals of similar breeding will frequently be of great value as a guide in the selection of the herd sire. TABLE VIII "Nicking" as Demonstrated in the Case of Imp. Rouge II's Son Average Production OF Dams Average Production OF Daughters Increase in Production Ov'ER Dams Cow No. Milk, Pounds Fat, Pounds Cow No. Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent 97 98 5288.9 7258.7 229.42 294-87 247 286 322 225 267 8385.4 8309 -3 8908. 5 6213.0 9772.8 400 . 58 394 74 470.70 294.16 473-38 57 57 68 — 14 35 75 73 105 61 Average. . . 6305-5 264.27 8019.2 388.42 27 47 123 1S6 187 6326.9 6854.9 8328.7 322.22 312.41 365-19 292 254 226 5546.8 5264.5 6650.3 271.79 282.71 335-46 — 12 -23 — 20 -16 — 10 - 8 Average. . . 7303-6 336-14 5875-3 301.62 — 20 — 10 Grand Average. 6631.0 286.98 7253-5 357-43 9 25 14 THE INDIVIDUAL COW AS A UNIT The breeding of a cow determines, to a very considerable extent, her producing ability, but it must be remembered that for best results the breeding stock must be carefully selected. Then some level of production should be aimed at, and individuals faihng to come up to this should be dis- posed of, as there will always be a few culls produced even in a well-bred herd, though the number will be fewer than in a herd of scrubs or grades. It is only by disposing of such cows that the production of a herd can be increased or even main- tained at a definite level. The individual cow is the most important factor in profitable dairying and only good produc- ing cows should be maintained. CHAPTER II THE IMPORTANCE OF FEEDING A GOOD COW is essential for profitable milk production, but before the cow can work efficiently, her needs for the materials from which milk is produced must be met. The cow pro- duces milk; but she must be supplied with the raw materials, in the form of feed, from which the milk is produced. The individual cow is the most important factor to be considered by the dairjonan, and ranking closely to this problem is the consideration of feeding. LIBERAL FEEDING ESSENTIAL Feeding costs money ; and too many endeavor to reduce the cost of milk production by stinting the feed of their cows. This is not good economy, as without the feed the cows cannot produce the milk, and the lower the milk and butter fat yield the greater the cost of production per unit of product, as a general rule. The economy of liberal feeding has been clearly pointed out in the work conducted at Iowa State College with the scrub cows already mentioned, and the advantages of such a system are clearly seen from the records of two cows that reached the Station when they were four years of age. The scrub cows had been subject to very poor care and had rustled most of their feed, but when they were given good feed and care in the College Herd they increased in production from their first year. Unfortunately, no records are available 15 16 THE IIMPORTANCE OF FEEDING VTI ^ Annual i'ro N ) 6 on \rn\ il it low i St ilc Colkgc at 4 \Larsof Age. moil 2586.4 Pounds of Milk and 137-94 Pounds of Fat. Fig. VIII.— Scrub Cow No. 6 at 7 Years of Age. Annual Production 5468.7 Pounds of Milk and 244.79 Pounds of Fat. LIBERAL FEEDING ESSENTIAL 17 as to the milk and butter fat they produced under their former conditions. In their fourth lactation at the Station they were producing, on the average, 4907.7 pounds of milk and 229.91 pounds of fat, or 59 per cent more milk and 54 per cent more fat than during their first lactation period. It is known TABLE IX Average Production of Scrubs put on Good Feed AT Four Years of Age Average Production Increase in Production Over First Lactation Lactation Age, Years No. Milk, Fat, Milk, Fat, Pounds Pounds Per Cent Per Cent I 4 3084 . 6 149-24 2 5 3984-4 178 97 29 19 3 6 4618. I 217 79 50 46 4 7 4907 • 7 229 91 59 54 5 8 4224.0 197 59 37 32 6 9 1991-3 84 76 -35 -43 7 10 2862.5 ^33 70 - 7 — 10 8 II 2296.2 93 83 -26 -36 that as cows mature they increase in production, but the increase that could be attributed to the aging of the animals from four to seven years would, on the average, be only 10 per cent in milk and 8 per cent in fat. The major portion of the increase obtained in this experiment must, therefore, be attributed to feeding. 18 THE IMPORTANCE OF FEEDING BEGINNING WITH THE YOUNG STOCK With these four-year-old cows there were some cows past their prime and a few immature heifers. A comparison of these three groups brings out another important point. TABLE X Comparison of Scrubs Subjected to Good Conditions at Different Ages Group Average Production Increase in Production Over Mature Cows Milk, Pounds Fat, Pounds Milk, Per Cent Fat, Per Cent 3168.7 3597-7 4036 . I 153-64 166.36 191. 21 14 27 8 Heifers 24 In making this comparison, allowance has been made for the age at which the records were made. It is found that the cows which had been kept under poor conditions until they reached maturity and had then been subjected to good treat- ment had the lowest average production; those that were put under good care at four years of age were the next best; while those that had been liberally fed from the time they were calves gave the most milk and butter fat, or 27 per cent more milk and 24 per cent more fat than was produced by the group kept under poor conditions till maturity was reached. Liberal feeding during the lactation period of a cow is essential, but just as important is the feeding of the dry stock and especially the growing heifers. If heifer calves that are being grown out to take their places in the herd are NECESSITY OF INDIVIDUAL FEEDING 19 poorly fed, they can not give the best results when they come to producing age. The potential dairy cow must be liberally fed from birth. NECESSITY OF INDIVIDUAL FEEDING The individual cow is the unit in profitable dairying, and the most important factor, in addition to the inherent ability of the cow to produce, is feeding. As a consequence, the feed requirements of each individual cow in the herd must be considered if the best results are to be obtained. The abiUty of the cow to produce and her feed requirements are very closely associated. It has long been known that animals of the same or similar breeding and reared under identical conditions will not always be alike in producing ability when they reach maturity. Several illustrations of this have already been given. The reasons for this were not understood until work was conducted at the Missouri Experiment Station in an attempt to elucidate the problem. At the outset it was recognized that this individual varia- tion in producing ability might be due to one or more of the following factors: variation in the digestive powers of the animals ; difference in the quantities of feed required for body maintenance; utilization of part of the ration for the pro- duction of body fat ; difference in the amount of feed actually used in addition to that required for maintenance. Two Jersey cows which were a little more than half sisters and of about the same age were used. Previously they had received the same treatment, though one had proved to be a much better producer than the other. A complete record of the feed consumption of the animals was kept; the rations fed were of the same composition but were varied in quantity to suit the needs of the individuals. Exact records of the yields and composition of the milk were obtained. 20 THE IMPORTANCE OE EEEDING The animals were kept barren and at uniform weight throughout the experiment. At the period of maximum pro- duction, digestion trials were conducted, and at the end of the lactation period maintenance trials were made, the feed used being the same in composition as that used during the lactation period. The ration consisted of corn silage, alfalfa hay and a grain mixture made up of four parts ground corn, two parts wheat bran and one part oil meal ; during a portion of the trial some green feed was also given. As the animals were maintained at a uniform weight the difiference in production could not have been due to the production of body fat by the inferior producer, and likewise it was found that the differences in digestive powers and maintenance requirements were too small to account for the large differences in milk and butter-fat yields. TABLE XI Feed Consumption and Milk and Butter fat Production of Two Cows OF Varying Producing Ability Cow No Total production: Milk Fat Total feed consumed: Grain Hay Silage Green feed Feed used for production: Grain Hay Silage Green feed Pounds 3189 169 1907 1698 50cS8 2102 841 632 796 NECESSITY OF INDIVIDUAL FEEDING 21 The total feed consumption of the two animals varied widely, but their maintenance requirements varied little. So when the feed needed for maintenance is deducted from the total amount consumed there is found to be a very wide dif- ference in the amounts of feed available for productive purposes. The ratio between the milk produced by the two cows was I : 2.67, and for the butter-fat production it was i : 2.77, which coincided very closely with the ratio between the various amounts of feed actually used for milk production. This clearly shows that the good producing cow is simply the one that uses a large amount of feed, in addition to that needed for maintenance purposes, and utilizes it for milk and butter-fat production. The problem of the feeder, therefore, is to provide the cow with the maximum amount of feed, in addition to what she requires for other purposes. She will convert this additional amount of feed into milk and butter fat, and the greater the amount of feed used for this purpose, the more economical will be the production of the cow. PART IT THE CHEMISTRY OF FEEDING CHAPTER III THE ELEMENTARY COMPOSITION OF FEEDS In a consideration of the feeding problem, little attention is, as a rule, given to the individual elements which, in com- bination, form the complex compounds of the plant and animal tissues; yet the science of chemistry shows that all substances are ultimately derived from the simple chemical elements. The feeding stuffs used for farm animals are gener- ally vegetable products, though a few animal products, such as tankage and skim milk, are utilized. These feeding stuffs consist of complex compounds, and a knowledge of the source of these compounds is of value. The animal elaborates the constituents of its body from the compounds existing in plants or animal products, but the plants used as sources of feeds must elaborate these compounds from simpler substances. As will be noted later, the carbohydrates, fats, proteins and ash are the main constituents derived by the animal from the plant products it consumes; the first problem, therefore, is to locate the source from which the plant obtains these substances. The plant makes them from the elements and from some simpler compounds elaborated from the elements. A very large number of elements are found in plants, in the form of compounds, but only a few of them need be con- sidered, as all of them are not essential for animal life. CARBON The element, carbon, which is the main constituent of coal, and in the practically pure state forms such widely different 25 26 THE ELEjMENTARV COMPOSITION OF FEEDS substances as tliamonds and lampljlack, lonns about 50 per cent of the dry matter of j)lants and animals. It occurs in the air as a constituent of the gas, carbon dioxide, which when present in appreciable amounts in buildings may lead to difficulties, as it is poisonous to animals. Green plants have the power of absorbing this carbon diox- ide through their leaves and other green parts, during the hours of sunlight. Then the green coloring matter, chloro- phyll, which is present, deriving energy from the sunlight, converts this carbon dioxide and water into sugar which can be carried to the various organs of the plant and there used for a variety of purposes. During this process oxygen is given ofT by the plant. In addition, the plant roots in the soil take up water, which has many compounds in solution, among them carbonates which contain carbon. HYDROGEN Hydrogen occurs in the free state as one of the gases of the air, and with oxygen it forms water. The main source of hydrogen for plants is the water taken up by the roots. Some of the salts in solution in this water also contain hydro- gen. Like carbon, it enters into the composition of a very large number of compounds occurring in the various tissues of plants and animals. OXYGEN This gaseous element is most familiar as one of the most important constituents of the atmosphere of which it forms about one-fifth. Its presence there is essential for all the higher plants and animals. It is also one of the constituents of water. The plants derive some of it from the air through their pores and also obtain a large amount of it from the water absorbed and a smaller amount from some of the compounds in solution in the water. NITROGEN 27 NITROGEN About four-fifths of the air is nitrogen, and one group of plants, the legumes, have the ability to use this atmospheric nitrogen for their own purposes. Their powers of utilizing this nitrogen are due to the presence of bacteria in the nodules on the roots. These bacteria, which receive some of their nutrients from the legumes, with which they are combined, take the nitrogen from the air in the soil and from it form compounds which can be utilized by the legumes. Other plants do not have this power and so are dependent for their supply of nitrogen on the nitrates which are absorbed in solu- tion by the roots. The legumes also obtain some nitrogen in this manner. Nitrogen is a characteristic constituent of the proteins of both plants and animals. POTASSIUM The element potassium is not known in the free state, but its compounds are common. Some of the most familiar are potassium carbonate and caustic potash. Immense deposits of potassium salts are known. Potassium salts in solution in the absorbed water form the only source of supply for plants. This holds true for all the other elements which remain to be mentioned, and which, together with potassium, form the ash or inorganic portion of the plant. SODIUM This element is also unknown in the free state, but some of its compounds are very well known, including sodium chloride, sodium carbonate and sodium bicarbonate, which are generally recognized as common salt, washing soda and baking soda. The salts of sodium occur in large deposits and, like those of potassium, form a large proportion of the ma- terials in solution in sea water. 28 THE ele:\ientary co:mposition of feeds CALCIUM Calcium is never found in the free state, but occurs in large quantities in nature as calcium carbonate in the form of lime- stone and chalk, while other compounds are also abundant. It is one of the most important ash constituents so far as animal nutrition is concerned, as it is a large component of bone. MAGNESIUM Though not found in the free state, magnesium exists in the form of many compounds which are frequently found in conjunction with those of calcium. It is not so plentiful as calcium in the ash of animals. IRON Iron ores are very abundant, and varying amounts of iron compounds are universally distributed throughout the soils. Only small amounts of iron are found in the free state. In addition to being found in the ash of plants and animals, iron occurs in some proteins and is quite characteristic of some of the compounds of the blood. SULPHUR Though most generally recognized as the yellow flowers of sulphur, this element occurs to a limited extent in the free state. Its most common occurrence is in such compounds as sulphates and sulphides, which are quite widely distributed. Sulphur is also found in some proteins, as well as in the ash of plants and animals. PHOSPHORUS Though widely distributed in combination in nature, phosphorus is never found free. It occurs generally in the IODINE 29 phosphates, which are sometimes found in large deposits. Some of the phosphates of calcium may be taken as an illustration, though many phosphates are widely distributed. Phosphorus occurs in some proteins, as well as in the ash of living organisms. IODINE Iodine never occurs in the free state in nature, though iodides and iodates, especially of sodium and potassium, are widely known. Iodine is best known in the crystalline form, but on being heated it forms a violet-colored vapor which crystallizes on cooling. Compounds of iodine are common in sea water and many sea weeds contain relatively large proportions of them. In other plants and in the animal body, iodine compounds occur in smaller proportions, though they have some very important, though poorly understood, functions to perform in animal metabohsm. CHLORINE The greenish-yellow, poisonous gas, chlorine, does not occur free in nature. Many of the compounds, into the formation of which it enters, are well known, the most familiar one being common salt, or sodium chloride. Chlorine is also one of the constituents of hydrochloric acid, which plays an important role in digestion. FLUORINE The gas fluorine does not occur free, and its best-known compound is calcium fluoride. It appears to derive its im- portance from the fact that it occurs in small amounts in the enamel of the teeth. 30 THE ELEMENTARY COMPOSITION OF FEEDS SILICON Silicon never occurs in the free state, but in combination it is, perhaps, with the possible exception of oxygen, the most widely distributed element. Its most common compound is silicon oxide, or silica, which is best known as quartz and, in the granular condition, as sand. In the form of silicates it is also one of the most important constituents of the clays. Though of no known importance in the animal body, it occurs to some extent in both plants and animals. CHAPTER IV THE CONSTITUENTS OF FEEDS Feeding stuffs arc not simple substances, but complex mixtures of intricate, though definite, chemical compounds, and as it is the utilization of these substances that is of importance in the feeding of animals, some knowledge of their nature is essential. In studying them from the feeding stand- point, however, it is not necessary to adhere strictly to a chemical discussion of the feed constituents; it is better to group them according to the functions which they perform in the animal body. All of the substances found in feeding stuffs need not necessarily be of value to the animals consuming the feed, and those which have value are generally grouped together as nutrients. A nutrient may be stated to be any feed con- stituent, or group of feed constituents of the same general chemical composition, that may aid in the support of animal life. Used in the broadest sense, the term nutrient would include the oxygen of the air and drinking water, as they are essential to animal life, though their general abundance generally excludes them from discussion. The feeding stuffs may be divided into water and dry mat- ter, the dry matter being considered the more important as it is generally more expensive. The dry matter contains a very large number of materials, and may be divided into organic matter and inorganic matter, or ash. The latter is generally considered as a whole, while the other substances included in the term dry matter are grouped according to 31 32 THE COXSTITITXTS OF FEEDS their chemical nature, as carbohydrates, fats and proteins. The terminologv" used in feeding work is not always free from chemical inexactitudes, but it is sufficient when con- sidering practical problems. WATER Water occurs in all feeding stufts and is of much greater importance than is generally realized. The amount of it present varies very considerably, as only about 5 per cent of it is found in some grains and hays, while it may constitute as much as 90 per cent of some roots. Water is composed of eight parts by weight of oxygen and one part of hydrogen. CARBOHYDRATES The carbohydrates form a very large group of compounds of diverse properties. They obtain their name from the fact that they consist of carbon, hydrogen and oxygen, and the hydrogen and oxygen are present in the proportions in which they occur in water. This definition brings in a few sub- stances, such as acetic acid, which are not carbohydrates. For feeding purposes the carbohydrates are div-ided into two main groups, the crude fiber, and the nitrogen-free extract. This is rather a vague grouping, but is quite suitable for practical purposes. Crude Fiber. — When a feed is boiled with dilute acid and then with dilute alkah, all the more readily soluble sub- stances are removed and the residue is known as crude fiber. This portion of the carbohydrate group is not a simple sub- stance; it consists of the woody, more insoluble portions, such as the cellulose and the Hgnin of the cell walls of the plant. Nitrogen-free Extract. — The nitrogen-free extract consists of a group of carbohydrates of similar nature and value. It is a very poorly defined group, as is shown by the method in which FATS 33 it is determined in the chemical examination of a feed. WTien all of the other main groups of nutrients have been determined, the undetermined portion is grouped as the nitrogen-free extract. Topical examples of this group of nutrients are sugar, starch and similar compounds. FATS The fats, like the carbohydrates, contain carbon, hydrogen and oxygen, but the hydrogen and oxygen are not in the same proportions as in water. The true fats are compounds of glycerol and the fatty acids; but as the method used in determining them in the analysis of feeds is quite crude, other substances are generally included with them. To de- termine the amount of fat in a feed the material is extracted with ether, and as the resulting extract generally contains waxes, coloring materials and other substances in addition to the true fats, it is classed as ether extract, or crude fat. The amounts of fat present in the different feeding stuffs vary widely, and typical examples of them are corn oil and lin- seed oil. PROTEINS More complex in composition than either the carbohydrates or the fats are the proteins. In addition to carbon, hydrogen and oxygen, they always contain nitrogen and sometimes sulphur, phosphorus and iron. Chemically they may be looked on generally as compounds containing amino-acids. In feed analysis the method of arrixdng at the amount of pro- tein present is to determine the percentage of nitrogen and multiply this by 6.25, as the arfiount of nitrogen in the various proteins in feeds is fairly constant. This method is not quite correct, however, as it also takes into consideration the nitrogen present in some non-protein substances which will be considered later. Where the protein is determined in this 34 THE CONSTITUENTS OF FEEDS way it is called crude protein, to distinguish it from the actual or true protein present. So far, twenty-two amino-acids have been determined in the proteins of feeding stuffs, and even these vary greatly in complexity. In addition to the amino-acids, other chemical groupings also occur in some of the more complex proteins. The value of proteins for feeding purposes depends on the specific amino-acids which they contain, a problem which will be discussed under the utilization of the nutrients. The proteins are the characteristic constituents of the animal body in contradistinction to the carbohydrates, which pre- dominate in plants. Some typical proteins are the albumin of egg-white, the caseinogen of milk and the gluten of wheat. NON-PROTEIN NITROGENOUS COMPOUNDS This is a poorly defined group of substances of doubtful feeding value. As already mentioned, they are generally included with the true protein under the term crude protein in the analysis of feeding stuffs, as their determination re- quires a considerable amount of chemical work. They do not generally occur in large amounts in feeds and are most fre- quently found in young, immature plants. One of the best- known substances in this group is asparagin, which occurs in asparagus and many other plants. VITAMINES The vitamines, or food accessories, have been only recently recognized as of importance in animal nutrition. Their functions are quite dissimilar to those of the other groups of substances mentioned here. Three so-called vitamines are now recognized. Fat-soluble A, Water-soluble B and Water- soluble C. Their names are derived from the substances in which they are dissolved, but so far their true chemical PIGMENTS 35 nature has not been determined, as they are present in feeds in extremely small proportions. Their distribution is not uniform throughout the feeding stuffs, but this can best be discussed in connection with their functions. PIGMENTS Pernaps the most characteristic coloring material of plants is the green pigment, chlorophyll; but of more importance, so far as the feeding of dairy cattle is concerned, is the group of yellow pigments known as the carotinoids. These are found associated with the green pigment and also alone, as in the case of carrots. The chief members of this series are carotin, which was first isolated from carrots and the xanthophylls. The pigments occur in plants in but small amounts and are of no known nutritive value, their importance being due to the influence they have on the color of milk. ASH Excluding the vitamincs and pigments, the ash is generally the smallest constituent of the common feeding stuffs, though by no means the least important. The ash contains a large number of inorganic compounds, and as it is determined by burning the feed and weighing the residue it also includes not only these inorganic compounds, but also constituents, such as "ron and phosphorus which occur in organic combina- tion in the feed. There is practically no limit to the variety of elements occurring in the ash, but among the more common are cal- cium, magnesium, sodium, potassium, phosphorus, sulphur, iron, chlorine and silicon. CHAPTER V DIGESTION AND ABSORPTION When an animal consumes feed, the material ingested is generally of no immediate value to it. The feed materials must be converted into forms which can be assimilated by the animal body; this is the function of digestion, which is followed closely by absorption, or the transference of the digested nutrients from the alimentary tract into the tissues of the animal. The processes of digestion and absorption are complicated ones and all is not yet known about them. A certain knowledge of these activities is necessary, however, for a proper understanding of the principles of feeding. The digestive processes of the farm animals, as well as those of man, are all based on the same broad general principles, though there are some wide modifications due to differences in the structure of the digestive tract and the character of the feed adapted to the use of the various types of animals. There is thus a closer relationship between the digestive processes in man and the pig than there is in those of the horse and the cow. Only those of the cow will be discussed here. In discussing digestion the best method appears to be to start with the feed as it is taken in at the mouth and carry it through the digestive system, noting the changes and actions which occur in each section. This method renders impossible the complete discussion of the digestion of any one nutrient at a time, but it permits all the functions of one organ to be discussed collectively. 36 THE MOUTH 37 THE MOUTH The first function of the mouth is the prehension of the feed, and in this process the long, rough-surfaced tongue plays an important part. The incisor teeth and the pad on the upper jaw are also used in biting off grass, though they are not so useful for this purpose in the case of the cow as they are in the case of the sheep. This is due to the absence of the spHt upper lip and explains why cattle do not cut pasture so close as do sheep. After the feed enters the mouth it is masticated rapidly and rather incompletely and swallowed. Later this feed is regurgitated, a process to be discussed further, and is then masticated slowly and thoroughly. This is known as cudding, or chewing the cud. In the process of mastication the jaws move not only upward and downward but also laterally, and feed is masticated only in one side of the mouth at a time. During the process of mastication the salivary glands per- form an important function. There are three pairs of these glands, known as the parotid, sublingual and submaxillary, and the ducts from one of each of the pairs pour out saliva in the right half of the mouth and the others in the left. The salivary glands are most active during mastication, but they also secrete to some extent even when mastication has stopped. Saliva consists mainly of water, but it contains a number of substances in solution, including two enzymes known as ptyalin and maltase. The first function of the saliva is to moisten the feed, both before it is swallowed and after it has been regurgitated for further mastication. The amount of saliva secreted depends largely on the nature of the feed; with dry feeds, such as hay and oats, large amounts of it are secreted while with silage or roots the secretion is reduced. Where dry feed only is provided, the 38 DISGESTIOX AND AHSURITKJX COW may secrete lo to 12 gallons or more of saliva daily. The mastication, or grinding of the feed into line particles, and the moistening of it with saliva are merely mechanical prep- arations to bring the feed into proper condition for true digestive action. The remaining function of the saliva is due to the presence of its two enz)TTies, ptyalin and maltase, and their actions are important. Enz>Tnes are substances of unique powers. Their composition or constitution is not understood, but they have the property of bringing about chemical changes without themselves forming any part of the resulting products. In fact, under suitable conditions, where the end products are removed, a very small quantity of enzyme can keep some chemical change going on continually and not be itself affected. The ptyalin of the saliva acts on the starch of the feed, which takes up water and is converted into maltose and dextrin. The maltase, which is of less importance, acts on the maltose and converts it into dextrose. It is essential for the operation of these enzymes that the medium in which they work contain no free acid, and so the saUva is normally alka- line in reaction. THE STOMACH In the horse and man, and, in fact, in all other mammals except the ruminants, there is but a simple stomach, whereas in the cow and other ruminants there are three other com- partments besides the true stomach. Sometimes these are all called stomachs, and the cow is then said to have a stomach with four compartments, or even four stomachs; but as a matter of fact she possesses a true stomach and three com- partments which are really enlargements of the oesophagus or gullet. In the order of their occurrence in the digestive tract, they are the rumen, reticulum, omasum and abomasum. THE STOMACH 39 Considering these four divisions as a whole, it may be said that they fill about three-fourths of the abdomen of the ruminant, the greater portion of them being in the left half of the body cavity. The total capacity of these compartments varies from 30 to 60 gallons, depending largely on the size and age of the animal. It must also be remembered that these compart- ments do not arrive at their final relative sizes until the animal is about one and a half years of age. Then the rumen constitutes about 80 per cent, the reticulum 5 per cent, the omasum 7 to 8 per cent and the abomasum 8 to 7 per cent of the total capacity. In the new-born calf conditions are very different; the rumen and reticulum combined are about half as large as the abomasum, and the omasum is small and apparently functionless. By the time the animal is about three months old the combined volume of the rumen and reticulum is about double that of the abomasum, and in another month they are about four times as large as the omasum and abomasum combined. From then on, the development continues until the various compartments reach their ultimate relative sizes. Rumen. — The rumen, or paunch, is not a simple cavity but is somewhat divided into sacs by muscular pillars, and the mucous membrane lining it is studded with small projec- tions or papilla?. Beginning at the point of entrance of the oesophagus into the rumen is the oesophageal groove. This is a canal with an incomplete wall. It passes along the edge of the rumen and ends at the opening to the reticulum and omasum. While the animal is feeding, most of the feed passes into the rumen. The rough, coarse feed and practically all the water goes there, though some water may go to the reticulum through the esophageal groove, and any excess may pass on to the omasum and abomasum. Some of the finer material 40 DIGESTION' AND ABSORPTION of the feed may also pass on through the oesophageal canal without really entering the rumen. The feed and water gathered in the rumen do not remain there inactive, as the mass is kept rotating, this action being most marked during rumination and just after drinking. The contents are thus thoroughly mixed. No true digestive fluids are secreted in the rumen, although some mucous material is hberated. Nevertheless, chemical action is continually going on. The enzymes brought to the rumen by the alkaline saliva continue to function. The con- tents of the rumen vary in reaction, however, some being alkaline on account of the saliva while other portions are rendered acid by fermentative processes going on in parts of the feed. Of the cellulose in the feed, about 15 per cent is digested by bacteria and by enzymes contained in the feed itself. Although these changes in the carbohydrates of the feed are taking place, the main function of the rumen is to store and macerate the feed and in this way prepare it for further digestion. When a cow starts to ruminate, the rumen becomes quite active and its contents are kept moving toward the oesophageal groove for the purpose of regurgitation. Then portions of the feed, about 4 ounces in weight, are separated from the main mass and returned to the mouth for mastication. Reticulum.— The oesophageal groove affords a means of communication between the oesophagus and the reticulum, or honeycomb, while communication between the rumen and reticulum over the wall separating them is easy, and there is also an orifice which serves as a means of communication between the reticulum and omasum. The mucous membrane lining the reticulum has the appear- ance of a honeycomb and secretes no digestive fluids. The contents are watery in nature and alkaline in reaction. As a rule feed does not pass into the reticulum and its main THE STOMACH 41 function seems to be in aiding rumination. The walls can be contracted and the alkaline fluid passed over into the rumen where it helps in the preparation of the feed for further digestion. One of the peculiarities of the reticulum is that it is here that the nails, old wire and other "objets d'art" swallowed by the cow are generally collected. Omasum.— The openings of the omasum, or manyplies, which communicate with the reticulum and abomasum are both on its lower side, and a groove in its lower wall forms a direct passage, for fluids and fine materials which need no further preparation, from the reticulum to the abomasum. The omasum is lined with leaves of various sizes and covered with horny papillae, the function of which is to macerate feed which has not been finely ground. It secretes no digestive fluid and takes no part in absorption, while its contents are neutral in reaction and normally dry. After rumination, the material swallowed passes through the oesophageal groove and to the omasum. Much of the liquid and finely ground material passes on through the groove in the lower surface of the omasum to the abomasum, but the other material is macerated by the leaves of the omasum and then passed on. It is probable that the changes started by the enzymes of the saliva, and by bacteria in the rumen and the enzymes of the feeds themselves, continue up to this time. Abomasum. — The abomasum, or true stomach, is the only one of the four so-called stomachs of the cow in which true digestion takes place. The abomasum is Hned with mucous membrane, in certain portions of which are located glands which secrete the various constituents of the gastric juice. The various sets of glands have different functions to perform, but the main constituents of the gastric juice are hydrochloric acid and the enzymes, pepsin, rennin and gastric lipase. The feed entering the abomasum is in a finely divided form and alkaline in reaction, and as it is gradually mixed with the 42 DISGESTION AND ABSORPTION gastric juice the hydrcxliloric acid renders it acid in reaction; but as the hydrochloric acid has, lirst of all, to unite with the alkali, it is some time before the action of the enzymes of the saliva ceases breaking down the starches and maltose. When the medium becomes acid the pepsin acts on the proteins, breaking them down into the simpler bodies, peptones and proteoses. This action is continued in the intestine. In older animals, the enzyme rennin appears to have little to do, but in the case of calves its function is important. Like pepsin, it acts only in an acid medium, and when the milk in the stomach of the calf has been rendered acid the rennin coagulates the protein, caseinogen, thus preparing it for the action of the pepsin. The gastric juice sets free the fats of the feed, mainly by the solution of the materials surrounding them, though when the fats are in a finely divided form, as in milk, the enzyme lipase may act on them, breaking them down into free fatty acids and glycerin. When the contents of the abomasum have become mixed with the gastric juice and a certain degree of acidity has been reached, the pylorus, which separates the abomasum from the small intestine, opens. Part of the con- tents then pass to the intestine. THE INTESTINE The intestine is not a simple canal but is divided into several more or less distinct sections. It is divided, in the first place, into the small intestine and the large intestine. The small intestine consists of the duodenum, jejunum and ileum, while the large intestine, which is wider but shorter than the small intestine, is made up of the caecum, the colon and the rectum. Small Intestine. — When the acid contents of the stomach enter the small intestine they meet an alkaline medium in the duodenum. The partial neutralization of this by the acid from the stomach leads to the closing of the pylorus, which THE INTESTINE 43 does not open again to allow of further feed passage until the material in the duodenum has been rendered alkaline. The walls of the small intestine are lined with a mucous membrane which secretes a digestive juice; the bile and the secretion from the pancreas also enter the duodenum. These secretions are all mixed with the material from the stomach and have an important part to play in intestinal digestion. When the partially digested feed, or ch^me, passes from the stomach to the intestine, the hydrochloric acid which it con- tains acts upon a substance called prosecretin, which is present in the mucous membrane of the duodenum and con- verts it into secretin. The secretin in turn is carried by the blood to the pancreas and stimulates the production of the pancreatic juice. The pancreatic juice is poured into the duodenum through two, ducts and, being alkaline in reaction, neutralizes the acidity of the chyme. In addition it contains three enzymes or the substances from which they are derived. These are trypsinogen, which is inactive in that form, amylase and steapsin. On entering the duodenum, the trypsinogen comes in contact with enter okinase which is formed in the mucous membrane of the intestine. The enterokinase con- verts the inactive trypsinogen into active trypsin, which acts on the proteins of the intestinal content and breaks them down further than was done by the pepsin of the stomach. The trypsin really completes the work started by the pepsin, and the end products of protein digestion are in the main amino- acids. The amylase of the pancreatic juice converts the starches into the sugar maltose and the steapsin splits the fats into fatty acids and glycerin. The bile is continually formed by the liver, and is stored in the gall bladder and forced into the duodenum when chyme enters thereinto from the stomach. The bile carries off a large amount of waste material, but plays sopie part in di- 44 DIGESTION AND ABSORPTION gestion, though this function is not well understood. It aids in the breaking down of the fats into fatty acids and glycerin, but the manner in which it acts is not known, though it greatly assists the steapsin or lipase of the pancreatic juice. The secretion of the gland cells of the small intestine is known as the succus entericus. Part of the functions of the small intestine, in the production of secretin and enterokinase, have already been mentioned; but in addition it produces a number of enzymes. One of these is erepsin, which converts the proteoses and peptones which have been formed in earlier protein digestion into amino-acids, while another is nuclease, which breaks up the complex nucleic acids into simpler com- pounds. In addition it contains a number of inverting enzymes maltase, invertase and lactase, which act on the disaccharides, such as maltose, sucrose and lactose, and con- vert them into simple sugars like glucose, fructose and galactose. These various enz>Tnes, acting in the small intestine, complete the changes started by those of the mouth and abomasum and finally prepare the material for absorption into the body of the animal. It is true also that stomach digestion is continued for a short time in the small intestine, until the chyme has been rendered alkaline. Absorption is the process by which the nutrients, which have been digested in the alimentary canal, are absorbed and taken into the circulation of the animal. It is probable that very little, if any, absorption takes place before the feed reaches the small intestine, but there it becomes very active. The surface of the small intestine is studded with millions of small processes known as villi, and it is through these that actual absorption takes place. The villi are copiously pro- vided with capillaries from the arterial and venous blood systems and from the lymph system. The lymphatics take up the products of fat digestion, while the capillaries of the THE INTESTINE 45 venous blood system absorb the end products of the digestion of proteins and carbohydrates, and in addition take up a large amount of water and ash materials. Large Intestine. — When the material from the small in- testine passes through the ileocaecal valve to the large intes- tine the activities of the enzymes acting in the small intestine continue and the process of absorption is completed there. The large intestine is lined with a smooth mucous membrane, free from villi; but it is provided amply with capillaries from the blood and lymph systems, and these perform the same functions as they did in the absorption process in the small intestine. Even in the rectum, the last division of the large intestine, this process continues. The processes of digestion and absorption are not ab- solutely efficient, and so not all of the materials in the feed are digested and not all of the digested materials are absorbed. The efficiency of the processes, of course, depends to a con- siderable extent on the nature of the feed. This means that a considerable amount of refuse is left, and to this are added waste materials cast off in the bile and by other routes. The material left in this way is passed from the body as the fasces. CHAPTER VI THE UTILIZATION OF NUTRIENTS The utilization of the nutrients in the animal body involves a large number of processes which are generally considered under the subject of nutrition. Without taking up all of the nutritive processes, however, some knowledge can be obtained of the uses to which the nutrients are put in the animal body and the ultimate benefits which the animal derives from them. THE BODY ACTIVITIES The various processes which go on in the animal body are innumerable and complex, and though some of them are fairly well understood, many of them must still be discussed theoretically or, at best, with but a mere approximation of the truth. Broadly, however, the body activities can be divided into two main groups — those connected with the maintenance of the body and those concerned with production. The term production includes such activities as growth, fattening, fetal development, milk production and work. All of these, with the exception of work, are of importance to the feeder of dairy cattle and must be given consideration. Maintenance. — When the live weight of an animal that is not working is kept uniform for a period of time, it is gener- ally considered as being on a maintenance ration. Practically, this is nearly correct, but technically it is not, as an animal may remain constant in live weight and yet not have uniform amounts of nutrients and energy stored in its body. This is due to the fact that the tissues may lose some dry matter and 46 THE BODY ACTIVITIES 47 receive an extra supply of water, and that at times protein may be replaced with fat, or vice versa, and so alter the amount of energy stored in the body. Whatever may be the conception of maintenance, nu- trients are necessary to maintain the animal, and as mainte- tenance of the animal and all its vital body functions is essential, the nutrients necessary for it must be supplied in the ration. Other nutrients must be provided over and above the maintenance requirements for the productive body activities. It is the production of something by the animal from the feed supplied that brings the returns to the farmer; mere maintenance is not sufficient. Fattening. — The fattening of animals is one form of produc- tion that is easily recognized. It consists simply of the production and deposition of fat in the body from the nu- trients supplied in the feed. It is of more importance with beef than with dairy cattle; but even with the latter it must not be overlooked, as the cow will not do her best work when in poor condition, and she should be in good condition before freshening, to ensure the supply of body nutrients which can be used in the next lactation for the production of milk and butter fat. One of the primal instincts of the animal is preservation. As a consequence of this and of the fact that less work has to be expended in using the nutrients for body maintenance than in using them for the production of body fat the animal uses the feed needed for maintenance more efficiently and with less waste than it does that used for fattening. However, there is httle difference in the efficiency with which the feed is utilized for those two groups of body activities. Growth. — The importance of growth is evident, and the provision of feed for this purpose must be made in the case of all young, immature animals. Too many of the failures of cows to produce profitably are due to the fact that they 48 THE UTTLIZATTOX OF NUTRIENTS have received poor feed in insufticienl amounts while still undergoing development. The efficiency with which feed is used for growth is somewhat less than in the case of fattening, probably due to the fact that more energy is used up in the conversion of nutrients into new tissue substance, in growth, than in the conversion of an equal amount of nutrients into body fat. Fetal Development. — In the case of the dairy cow, the regular production of a calf is essential to true economy, and nutrients must be provided for the development of the fetus. From the limited amount of work available it appears that the nutrients are used less efficiently for the development of the fetus than for any of the general body activities first mentioned. This is undoubtedly due to the fact that the formation of a new individual requires the expenditure of even relatively more energy than is needed in the growth activities. Milk Production. — The nutrients supplied to a cow for the production of milk and butter fat are used more efficiently than those supplied for any other productive purpose or even for maintenance. This is perhaps due to the fact that it is easier to convert feed fat into milk fat, feed protein into milk protein, and so on, than it is to convert all feed nutrients into body fat or body protein, even to use them simply for maintenance. This is in spite of the fact that the nutrients are to some extent used interchangeably for the formation of milk sugilr and butter fat. It is simply a demonstration of one of the great fundamental functions of all living or- ganisms — preservation of the race: the cow can use her feed more efficiently for the production of milk, presumably to feed her calf, than she can use it for her own maintenance. It is this fact, more than any other, which makes the cow the most efficient of farm animals, so far as the conversion of farm products into human food is concerned. COMPARISON OF THE NUTRIENTS 49 COMPARISON OF THE NUTRIENTS The nutrients are used for a variety of purposes and in some cases they can be used interchangeably. As a conse- quence some methods of comparison are essential to a proper understanding of their interrelationships. Digestibility. — Not all the nutrients consumed by an animal are utilized in its vital processes. As the feed passes through the alimentary tract it is acted on by the digestive juices and a part of its nutrients absorbed there. This por- tion absorbed in the digestive tract is known as the digestible portion and includes the digestible protein, digestible fat and digestible carbohydrates. These must be taken into con- sideration in studying the value of a ration to animals. The average percentage of a nutrient digested from a feed is called the coefficient of digestibility, or digestion coefficient, for that nutrient in the feed. The feed not digested passes out in the faeces. Digestible Carbohydrate Equivalent. — It has already been noted that the carbohydrates and fats are the chief sources of energy for the animal body, and it has been found con- venient to use the term carbohydrate equivalent for these two energy-supplying nutrients taken together, so that they may be compared on a common basis. The digestible carbohydrate equivalent of a feed is its percentage of diges- tible carbohydrates plus 2.25 times its percentage of digestible fat, as one pound of fat will provide 2.25 times as much energy as will a pound of carbohydrates. Total Digestible Nutrients.— The term total digestible nu- trients signifies the sum of the digestible crude protein and the digestible carbohydrate equivalent. Owing to the fact that fat is more valuable for energy-producing purposes than are carbohydrates, this sum is a better indication of the 50 THE UTILIZATION OF NUTRIENTS value of a feed than would be the sum of the digestible crude protein, digestible carbohydrates and digestible fat. Nutritive Ratio. — A knowledge of the relation of the pro- tein to the non-protein constituents of a feed is frequently desired. This relation is expressed by the nutritive ratio, which is the ratio of the digestible crude protein to the di- gestible carboh3'drate equivalent of a feed. Energy Values. — It has been found that a knowledge of the digestible nutrients of a ration does not always give a true indication of the ultimate value of the ration to an animal. This is due to the fact that the animal body is a transformer of energy, and equal weights of digestible nutrients do not necessarily provide equivalent amounts of energy. Con- sequently some other measure of value for feeds is often needed in addition to those already mentioned. Energy may be defined as the capacity for doing work, and as heat is a form of energy which is easily measured, and as other forms of energy can be expressed in terms of heat energy, the heat which a feed can pro\dde is taken as a meas- ure of its energy value. The unit of measurement for heat energy used in nutrition work is the therm, which is the amount of heat required to raise the temperature of one thousand kilograms of water one degree Centigrade or of one thousand pounds of water nearly four degrees Fahrenheit. The amount of heat obtained by completely oxidizing a feed, or burning it in a good supply of oxygen, is its gross energy. This represents what the animal could obtain from the feed in the way of heat or other forms of energy if the processes of nutrition were absolutely efficient. However, there are many losses which must be taken into consideration. The first series of these occur before the nutrients have had the opportunity of entering into the metabolic processes of the animal. The energy lost in this way is carried away by the excreta. The faeces contain a COMPARISON OF THE NUTRIENTS 51 large amount of undigested material and, in addition, ex- cretory products, such as some of the constituents of the bile, which contain materials that are incompletely oxidized. The intestinal gases consist of methane and other materials which could be further oxidized. In the urine also urea and other materials pass off, which if completely oxidized would provide some energy, while the secretions of the sweat and sebaceous glands of the skin and the cast-off hair also contain substances carrying off energy from the animal body. When the energy contained in all these materials is deducted from the gross energy of the feed the metabolizable energy is left. It may be defined briefly as the gross energy of the feed less the gross energy of the excreta; it constitutes the maxi- mum amount of energy which the feed can actually contribute to the energy in the animal body. However, there are some losses from the metabolizable energy. The mechanical work involved in the prehension and mastication of the feed and in its transportation through the digestive tract involve an expenditure of energy. An additional amount of energy is also used by the salivary and other glands of the digestive tract in the preparation of their secretions for action on the feed. It is possible that digestion and absorption and the changes taking place in the nutrients after absorption may also involve an expenditure of energy, though this is not certain. It is known, however, that the actual presence of the nutrients in the cells of the body does lead to greater heat production. All of this second series of losses of energy are directly due to the consumption of the feed; and the metabolizable energy, less the energy expended in these processes, is termed the net energy value of the feed. The term net energy ex- presses the gain of energy to the animal body that results from the consumption of the feed. 52 THE UTILIZATION OF NUTRIENTS FUNCTIONS OF THE NUTRIENTS The various classes of nutrients have dehnite functions to perform in the animal body, though in some cases the duties of one nutrient can be taken over to a certain extent by nutrients of another class. Only a few of the general func- tions can be considered, however, as many of the inter- relationships of the nutrients are not yet understood. Water. — Water is absolutely essential to animal life. It probably has more functions to perform in the animal body than any other nutrient. First of all, the water supplied to a cow, either in the feed or as drinking water, plays an im- portant part in the digestion and absorption of other nu- trients. It is also required for the preservation of the tur- gidity of the tissue cells and as a means of rendering possible, through solution, the transportation of the other nutrients from one part of the body to another and to the fetus and mammary glands. Its importance in the production of milk is easily seen when it is known that 87 per cent of milk is water. In addition to these functions, water enters into chemical combination with other nutrients and is thus used in the actual building up of tissue. It aids in the proper elimination of undigested materials in the faeces and is absolutely essential for the carrying away of waste products in the urine. It is also a regulator of body temperature. Carbohydrates. — The two groups of carbohydrates, crude fiber and nitrogen-free extract, fulfill very similar functions in the animal body, but they should be considered apart. The crude fiber performs a very miportant function in the alimentary tract. For ruminants, a bulky ration is necessary to stimulate proper digestion, and the crude fiber of the ration has much to do in rendering the ration bulky, though FUNCTIONS OF THE NUTRIENTS 53 Other constituents also play their part. In other ways the functions of the crude liber are the same as those of the nitrogen-free extract. The main function of the nitrogen-free extract is to provide heat and energy to the animal body. The nitrogen-free ex- tract, with the crude fiber, forms the main source of these. It may also be converted into fat and stored in the animal body as such, or it may be used in the production of milk fat and sugar. Fats. — The fats are more concentrated heat producers than any other of the groups of nutrients. They help in the production of the fat and sugar in milk and are also used as material to be stored up in the body. Each pound of fat is capable of producing 2.25 times as much heat or energy as a pound of protein or carbohydrate. Proteins. — The proteins are used for building up new tissue and replacing tissues that are worn out. They are absolutely essential to the welfare of the animal. When more protein than is necessary for tissue building is supplied, it can be used for the production of heat and energy, or part of it may be converted into body fat. In pregnant animals proteins are required for the growth of the fetus and its enveloping membranes. After parturi- tion a considerable amount of protein is used in the produc- tion of the milk proteins and may also be used, if present in the feed in sufficient quantity, for the formation of milk sugar and fat. Non-protein Nitrogenous Compounds. — The statements just made apj^ly to the crude protein, though the non-protein nitrogenous constituents are not as valuable to the animal body as are the true proteins. However, when true proteins are lacking in the feed, and a sufficiency of non-nitrogenous organic constituents is present, they can take the place of true protein to a certain extent in animal metabolism. 54 THE UTILIZATION Or XUTRIF.XTS Vitamines. — For the (lair\- cow, the absolute necessity of the vitamines, or food accessories, has jjerhaps never been definitely proved. The amounts stored in the body, though of vegetable origin, are large enough to carry the animal through very long periods, and when she goes to pasture she probably has their stores replenished. The vitamines, of which three are now recognized, are necessary for normal maintenance, growth and reproduction, and are even absolutely essential for life itself. In the case of the cow a supply of vitamines in the feed is especially necessary, in order that the normal amount of them may occur in the milk. Work at the Iowa Agricultural Experi- ment Station perhaps indicates the necessity of vitamines for calves, and elsewhere results are being obtained which in- dicate that the cow will tend to produce a vitamine-free milk if sufficient vitamines are not provided in the ration. Most of the information available has been obtained through experimental work with laboratory animals, and studies of the dietaries of humans where certain deficiency diseases occur. Unfortunately, little is known of the actual nature of the vitamines. It is known, however, that their absence from the diet leads to deficiency diseases which are frequently accompanied or followed by other diseases which take hold on account of the general weakness of the subject. The vitamines are believed to be nuclear nourishers, and many cases of indisposition may be due to too lov/ a supply of vitamines. The vitamines are all of vegetable origin and are essential for all the higher animals. While they do occur in certain animal tissues and products, even in those cases they are originally derived from vegetable products. The herbivorous animals get their supply direct from the plants, while the carnivorous animals derive their supply from certain organs of their victims. The formation of vitamines in the animal FUNCTIONS OF THE NUTRIENTS 55 body has not been demonstrated. An adequacy of vitamines is needed for both old and young, though this necessity is generally most evident in the case of the latter. The lack of Fat-soluble A leads to the eye disease known as xerophthalmia, and rickets are also attributed to it. Absence of Fat-soluble A for a sufficient length of time results in death. The most important source of this vitamine is butter fat and the quantity of it present ultimately depends on the feed of the cow. The chief vegetable sources of Fat-soluble A, from which the cow derives her supply, are the leafy forages, such as grass, clover, alfalfa and cabbage. Yellow corn may contain enough of it, but white corn is valueless as a source of Fat-soluble A. Colored roots, as carrots and sweet po- tatoes, contain it, but sugar beets, mangels and potatoes have little or none. It should be noted that all of the sources of Fat-soluble A mentioned have yellow coloring matter, though in some cases it is associated with the green pigment, chlorophyll. It may be that Fat-soluble A is a yellow plant pigment or a closely related compound. The absence of Water-soluble B from the ration leads to polyneuritis or beriberi in man and animals, and for this reason this vitamine is frequently called the anti-neuritic vitamine. Its absence from the ration will ultimately lead to the death of animals. One of the noticeable changes due to prolonged lack of Water-soluble B is atrophy of the testicles and ovaries. The decrease in size may exceed 90 per cent in the case of the testicles and 60 per cent in the case of the ovaries. This results in steriHty. Water-soluble B is not so abundant in milk as is Fat-soluble A, but it occurs. in the seeds of cereals and in a number of leguminous seeds, such as beans, peas and soybeans, cabbage, potatoes, carrots, turnips and beet roots. It is found most abundantly in the germ of the cereal grains, and ordinary 56 THE UTILIZATION OF NUTRIENTS bran contains little. It is found in the green forages such as the grasses and legumes, but the hays contain little of it. The vitamine known as Water-soluble C is anti-scorbutic, that is, it prevents the onset of, and cures, scurvy. Its absence from the ration ultimately results in death. It is needed by both young and old. The anti-scorbutic vitamine occurs in small amounts in milk, and it is found in green plants and in such feeds as cabbages, beet roots, and carrots, though it has not been detected in the seeds of cereals or legumes. The vitamines are essential for all animals, but where the cow is provided with a ration containing plenty of variety and some succulence she will seldom lack them in her ration. Pigments. — Until recent years little was known regarding the coloring materials present in milk, but it has now been shown at the Missouri Agricultural Experiment Station that the pigments of milk are interesting in character. One group of pigments, the carotinoids, consist of carotin and xantho- phylls, and as they are associated with the butter fat they are called the lipochrome, while another pigment found in solution in the milk serum is called lactochrome. Carotin and the xanthophylls are closely related sub- stances which are found widely scattered in plants and are always present in the chlorophyll-bearing parts. It has been shown that those coloring materials, when present in milk and in the bodies of animals, are identical with the plant pigments. The two classes of pigments mentioned above are intimately connected with the fat globules present — probably as adsorption compounds. They are not made in the body of the animal but are derived directly from the feed pigments. It has been shown that feeds rich in these pigments will color the butter fat highly and that the withdrawal of these sub- stances from the feed will after a time result in a loss of color by the butter fat. The delay in this loss of color is due to the FUNCTIONS OF THE NUTRIENTS 57 fact that some pigment is stored up in the body when excess of it is fed and this can hitcr be drawn on for the coloring of the butter fat. The rich color of milk in summer is due to the large amounts of carotin and xanthophylls in the green feeds consumed, while the white butter found in winter time is usually due to a lack of these constituents in the feed. There is some variation among the breeds of dairy cattle in respect to the maximum color of the milk fat under con- ditions equally favorable for the production of a high color. The Guernsey breed produces milk notably rich in these pigments, while the butter from Holstein milk is relatively poorly pigmented. Many people believe that the degree of pigmentation of milk varies directly with the percentage of fat present and so are willing to pay a higher price for yellow milk than they otherwise would; consequently, milk pigments have a tangible commercial value in some sections. Normally all cows produce a highly colored milk fat for a short time after parturition. Probably much of this pigment comes from the supply stored in the body, chiefly in the fat, and it is made available for the milk by the physiological conditions attending the secretion of milk about the time of freshening. As already stated, the yellow pigments in the fat and other parts of the body are the same as those found asso- ciated with the milk fat. Similarly, the yellow secretions of the skin so characteristic of the Guernsey, but also found in less profusion in the case of other breeds, contain xanthophyll and carotin. There is a correlation between the color of this secretion and the color of the milk, but the presence of an abundant yellow skin secretion does not indicate that an animal will produce highly colored milk under all conditions; the pigments must be supplied in the feed before they will appear in the milk. Evidently some breeds, and individuals 58 THE UTILIZATION OF NUTRIENTS within the breeds, are more susceptible to pigments than are others. The lipochrome, or fat pigment, in milk is composed largely of carotin, the xanthophylls being present in small quantities only. This is due to the fact that carotin is assimilated from the feed of the cow in preference to the xanthophylls, perhaps partly because of its greater stability toward the juices of the digestive tract. The carotin, as carried by the blood to the udder, is in firm combination with an albumin. The lactalbumin of cow's milk may be related to the color of the milk fat, and there appears to be a special relation between the high color and the high albumin content of colostrum. The carotinoids in the milk are derived di- rectly by way of the digestive system and the blood stream from the carotinoids of the feed. It has been shown that there are individual and breed variations in ability to use those pigments, and generic variations also occur. The color in the fat of cows' milk consists mainly of carotin, while in the case of sheep and goats the xanthophylls predominate, even when the feed is very similar to that given to cows. Lactochrome, the third pigment, is the one that colors whey. It is closely related to, if not identical with, the yellow pigment of normal urine — namely, urochrome. The breed of the cow is the most important factor in determin- ing the amount of lactochrome in milk. It is the amount of lactochrome present that causes skimmed Jersey milk to appear richer than skimmed Holstein milk or sometimes even richer than whole Holstein milk. Ash. — The ash, though usually the smallest constituent of a feed, is very important. It helps to build up and keep in repair the skeleton of the animal, and also the skeleton of the fetus of the pregnant female. In addition it takes part in many other important functions which, though less evident, are vital. Its presence in all living cells is essential and it FUNCTIONS OF THE NUTRIENTS 59 aids in the functioning of the nerves, the maintaining of the muscles in proper working condition, and the circulation of the blood. It is also responsible for the ash constituents of milk. CHAPTER VII THE INFLUENCE OF NUTRITION ON PRODUCTION Because the ultimate source of milk, with all its con- stituents, is in the nutrients taken from the feed, it is interest- ing to note just what direct influence, if any, the nutrients of the ration have on milk production. INDIVIDUAL NUTRIENTS Each group of nutrients, such as the carbohydrates, fats and proteins, is made up of a large number of individual and distinct compounds. It is not possible to discuss these com- pounds in detail, but the main groups need attention. Water. — The water consumed by the cow, either in the feed or as drinking water, is used in large quantities for milk production. There is no doubt that limiting the water supply of a milking herd will decrease the production of milk. Any factor which tends to decrease the total yield of milk also tends to increase the percentage of fat and other solids present, but the total yield of these will generally be decreased. Con- sequently if the amount of water in the ration is limited, the yield of both milk and butter fat will be decreased. Carbohydrates. — The carbohydrates are used for the elab- oration of both milk sugar and butter fat, but those materials can be made even in the absence of carbohydrates. The carbohydrates, as a group, have no direct influence on the yield or composition of the milk. GO INDIVIDUAL NUTRIENTS 61 Fats. — The fats, perhaps more than any other class of nutrients, have been looked on as having a direct influence on the yield and composition of milk. However, this is in the man incorrect. The fats of the feed are used for the pro- duction of both fat and sugar in the milk, but normally they do not have any direct influence on the yield or composition of the milk. Sometimes, however, if the amount of fat or oil in the ration be increased markedly or suddenly there will be a temporary increase in the percentage of fat in the milk, and this may lead, depending on the change in the milk yield, to a comparatively small and temporary increase in the fat yield. On the whole, however, the fats in the feed have no influence on the yield or composition of milk. Though this is true, the fats or oils of the ration may affect the butter fat in another way. Certain feeds, such as Hnseed-oil meal, peanut meal and the gluten products, which contain a fat or oil of low melting point, tend to produce a soft butter, as the fats from the feed or their fatty acids are used to some extent in the elaboration of the butter fat. In the same way, feeds, such as cottonseed meal, which con- tain fats of high melting point, tend to produce a hard butter. Proteins.— The proteins are one of the most important groups of nutrients so far as milk production is concerned, as most of their functions cannot be fulfilled by nutrients of other groups. Amount of Protein. — The protein of the feed is necessary for the production of milk protein and, when supplied in excess, can also be used for the production of the sugar and fat in the milk. It has been found that the supply of protein, if sufficient, has no influence on the composition of milk, and if proteins are deficient in amount they can be replaced to some extent, as already mentioned, by the non-protein nitrogenous compounds of the feed and by the use of body protein. 62 THE INFLUKNCE OF NUTRITION ON PRODUCTION Much work has been done on the influence of protein on the total yield of milk and, although it has no influence on the composition of milk, it is very evident that a suflicient supply of protein must be provided if maximum production is to be obtained. It is not sufficient to provide just the amount of protein that the cow needs for maintenance, milk production and other purposes; some additional protein should be pro- vided. This is due to the fact that the proteins are the only nutrients which actually stimulate milk production and a small excess of protein in the ration will generally lead to increased production. Too great an excess should not be provided, however, as this taxes the activity of certain groups of the body cells and ultimately results in lowered production. Nature of Protein. — A fact that has only been recognized in recent years is that the nature, or quality, of the protein, as well as the amount of it, in the ration is of importance in connection with milk production. Proteins consist essen- tially of amino-acids with a few other constituents, and it is the nature of the amino-acids present which determines the value of a protein. Of the twenty-two amino-acids which occur in proteins, a few are of special importance. Of these, tryptophane is absolutely necessary for life and maintenance, and lysine for growth, while histidine, cystine and arginine, though not absolutely essential, aid growth. It can be seen therefore, that all of these five amino-acids are essential in the ration if best results are to be obtained. The point of greatest importance in this connection is that all feeds do not contain all of the essential amino-acids. Feeds from a single-plant source are apt to be deficient in one or more of them. To avoid this deficiency, feeds from a number of plant sources should be given, as feeds from one source may frequently correct the protein deficiencies of those from another. Knowledge on this point is still in an ele- PLANE OF NUTRITION 63 mentary state, but it has been shown with milk cows that a good mixed ration is better for production purposes than one made up from one source only, such as the corn plant. Non-protein Nitrogenous Compounds. — The non-protein nitrogenous compounds play but little part in the production of milk and have no influence on its yield or composition. Vitamines. — As the vitamines in milk are derived from those in the feed of the cow, a vitamine-free ration would lead to a lack of vitamines in the milk and ultimately to a de- creased production; the presence of vitamines is necessary to the well-being of the animal. Pigments. — The pigments have no influence on the yield or composition of milk, though they do influence its color. Ash. — As long as sufficient ash is present in the ration, the yield and composition of the milk is unaltered. If the ration is deficient in some ash constituent the cow will draw on the stores of ash in her own body to supply the necessary ma- terials. When these body supplies run low the cow will still secrete milk of normal composition, but it will be decreased in amount. Eventually the cow will cease secreting to pre- serve the necessary minimum of ash constituents in her own body. PLANE OF NUTRITION The influence of the plane of nutrition on production can really only be studied by varying the plane of nutrition from normal and noting the changes that occur. The results given here regarding both high and low planes of nutrition are from work reported at the Missouri Agricultural Experiment Station. Overfeeding. — It has been found that the chief efifect of overfeeding is in the increased weight of the animal. There are no marked changes in the percentage composition of the milk or in the nature of the butter fat, though overfeeding has tJ4 THE INFLUENCE OF NUTRITION ON PRODUCTION a tendency to bring the composition of llie milk and of the butter fat back to normal when some factor has been active in causing variations from the normal. Only in some cases does overfeeding tend to increase the total yield of milk, and even then the influence is quite limited. On the whole, therefore, ()\erfeeding has no specific in- fluence on milk production, but it is a well-known fact that continuous overfeeding for a long period will result in the cow getting into very high condition, and that this will result in a decreased milk yield. Underfeeding. — Underfeeding may be brought about in- tentionally, but there is another type of underfeeding which cannot be controlled. This is physiological underfeeding, and it very frequently occurs just after a cow freshens. At that time she is giving her maximum amount of milk and does not appear to be able to digest enough nutrients to meet the requirements of the mammary glands. Underfeeding of either type results in a decrease in the weight of the animal. A reduction from a high to a low plane of nutrition leads to a high percentage of fat in the milk, especially if the cow is in good condition. The yield of milk is not decreased by physiological underfeeding or by underfeeding of any t^-pe just after parturition, but under- feeding later in the lactation period will result in a decrease in milk production. Subnormal nutrition, due to other than physiological causes, has a varying eiTect on the percentage of fat and other solids in milk. This should not be confused with the earlier statements made. The influence of under- feeding on the yield and composition of milk is consequently seen to be more marked than the influence of overfeeding. In studying the influence of the nutrients on production it should be remembered that the cow tends, above all things, to keep the milk normal in composition, and when any nutrient, which cannot be replaced by another, is lacking in PLANE OF NUTRITION 65 the ration, the cow will draw on the stores of that nutrient in her body to make up the deficiency. When the body sup- plies run low enough to be near the danger point three courses are open to the cow: to decrease the milk yield, to alter the composition of the milk or to die. She almost invariably follows the first course. PART JIT THE REQUIREMENTS OF THE ANIMAL CHAPTER VIII FEEDING STANDARDS For over a century attempts have been made at outlining feeding standards for farm animals. There have been re- peated efforts to determine definitely a scheme which would show the amounts of nutrients required by the various types of animals for maintenance, growth, fattening, the develop- ment of the fetus and milk production. The different stand- ards propounded have met with varying degrees of success. DEVELOPMENT About the beginning of the nineteenth century the interest of many workers began to center in the compilation of feeding standards for farm animals. The first standards were ob- tained from feeding trials in which one feed was substituted for another and the results compared. One of the feeds used was then taken as the unit of measurement and the values of the other feeds expressed in terms of a certain unit weight of the standard feed. Later it was found that owing to varia- tions in the composition and digcstibihty of feeds this method was not absolutely reliable, and other t>pes of standards had to be evolved. Thaer, in 1809, was the first investigator to propose what ran be called a feeding standard. His standard was based on the relative substitution values of feeds, the unit being a standard weight of good meadow hay. This work was the beginning of our present feeding standards and has been 69 70 FEEDIXG STANDARDS very much modified. In Denmark and other Scandinavian countries there is in use at the present day a Feed-unit System, which is simply a sUght modification of the Thaer Standard. This Scandinavian Feed-unit System is based largely on the work of Fjord. The feeding value of a definite weight of mixed grain is called one feed unit, and the values of all feeds are expressed in terms of this. In 1910 Hansson proposed a standard for dairy cows according to the Feed-unit System. He stated the requirements in terms of digestible protein and feed units. Haubner, about 1840, and Lingenthal, in 1857, were the first really to attract attention to the fact that feeding stand- ards should be based on the nutrients in feeds rather than on the gross weights of the feeds. In 1858 Grouven formu- lated a feeding standard based upon the crude protein, carboyhdrates and fats in feeds. He saw that owing to the wide variations in feeds something more definite than a Feed-unit System was desirable and he also made allowance for differences in the weights of animals. Soon after this, Henneberg and Stohmann showed, as the result of digestion trials, that the amount of total nutrients in a feed does not form an accurate guide to its nutritive value and that digestible nutrients are a more accurate guide. In 1 86 1, Kuhn first drew attention to the probable inadvisa- bihty of feeding all cows alike, irrespective of production or quahty of feed; while in 1864, as the results of further work, WolfT proposed another standard based on digestible nutrients and made allowance for differences in the live weights of the animals. Later Kuhn proposed a standard which was more flexible than Wolff's and which distinguished between true protein and non-protein nitrogenous substances. In 1879, Lehmann modified the Wolff standard and made allowance for the amount of milk being produced by a cow. Up to this time all the work on feeding standards had been DEVELOPMENT 71 conducted in Europe, but from work done in 1894 and sub- sequent years, Haecker, of the Minnesota Experiment Sta- tion, proposed a standard which was based on the digestible crude protein, carbohydrates and fat, and which took into consideration not only the weight of the cow and the amount of milk being produced, but also the richness of the milk, Haecker has considerably modified his standard since he first proposed it, and it must be looked on as one of the great advances in the formulation of feeding standards. Work by Kellner and Armsby has shown that there is a fallacy in using the digestible nutrients of feeds as a basis for feeding standards without paying attention to the source of the feeds. In 1907 Kellner published a standard which took into account the weight of the animal and the weight of milk produced. He made no definite allowances for milks of various qualities, but by allowing a variation in the amounts of nutrients required for each pound of milk he reached the same end. His standard is based on digestible true protein and starch equivalent. Armsby, of the Pcnnslyvania Agricultural Experiment Station, by the use of the respiration calorimeter, was able to determine the net energy used by animals for various purposes and the amounts of it supplied by different feeds. With his results he formulated a feeding standard which was based on the requirements of the animal for digestible true protein and net energy. He allowed for the weight of the animal and the amount of milk, but not for the richness of the milk. In 1913, Eckles, of the Missouri Agricultural Experiment Station, taking Armsby's standard for maintenance as his basis, formulated a standard for production, based on the yield and quality of milk and expressed in terms of digestible true protein and net energy, while in 191 6 Armsby proposed a standard for milk production which is a modification of the one just mentioned. 72 FEEDING STANDARDS Savage, of Cornell, published in 1912 a study on feeding standards recommending a feeding standard which was a modification of the Haecker standard and was expressed in terms of digestible crude protein and total digestible nutrients. From work done at the Wisconsin Station, Woll and Humphrey proposed a standard based on the total dry matter, digestible crude protein and total digestible nutrients; while Morrison, as a result of the work of Haecker and Savage, proposed in 191 5 a modification of the Wolff-Lehmann Standard, expressed in terms of digestible crude protein and total digestible nutrients. Since then, Morrison has modified his standard after consideration of other work. He now allows for a range in the requirements for both digestible crude protein and total digestible nutrients. This is the standard given in Appendix II. There are decided advantages in this standard. It allows variations in the amounts of nutrients supplied, so that the requirements of the individual cow can be more easily met. Again, it allows the changing of the relative amounts of protein supplied. This is very desirable, because in some localities, such as the South and the alfalfa regions, protein may at times be relatively cheap and so can be economically fed in greater proportions than would otherwise be the case. CRITICISMS For the purpose of discussing the relative values of the feeding standards and their general use, they can easily be divided into four groups, according to the nature of the terms in which they are expressed. Standards of the same type, though varying somewhat in their requirements, are all subject to the same general limitations. Standards Based on Gross Weight. -The main objection to standards of this class is that feeds vary not onl\' in the amounts of dry matter which they contain, but also in the CRITICISMS 73 relative proportions of the \arious nutrients which constitute the dry matter. Owing to these variations and to the fact that the digestibihty of the nutrients and the amounts of net energy which they provide also var}' the different feeds cannot be accurately compared for nutritive purposes on the basis of their gross weights. On the other hand, standards such as the Scandinavian Feed- unit System have some distinct advantages. They are very practical and easy to use. They are extremely useful as a guide to the economy of production of the animals within a herd or even of herds in a limited community. In this case the feeds used are all very similar in composition and so the error due to variations in the composition of different samples of a given feed are reduced to a minimum. In the cow- testing associations of Scandinavia this system is used widely and has given very satisfactory results. Standards Based on Total Nutrients. — These standards are free from the first objection to the standards already dis- cussed as they take into consideration the total nutrients in the feeds. However, the nutrients present vary in digesti- bility and as it is only the digestible nutrients that are of value in nutrition these standards also are quite inaccurate. Standards Based on Digestible Nutrients. — Standards of this class are a considerable improvement over those of the two previous groups. They eliminate the main errors due to the variations in composition and digestibility of the feeds. The earlier standards of this type made no allowance for variations in the weight of the animal, the yield of milk or the composition of the milk. The Kuhn Standard was the first of these to be really flexible, while the Wolff-Lehmann Standard made some allowance for variation in the amount of milk produced, though Haecker and other modern investi- gators belie\'e that the Aariations given were not as wide as they might be. 74 FEEDING STANDARDS The Wolff-Lehmann Standard, which was the leacHng one for many years, made no allowance for \-ariations in the composition of the milk; and to Haecker, of Minnesota, is due the credit of ha\ing proposed the first feeding standard that made allowance for this. The work of Haecker ap- peared to show that the Wolff-Lehmann Standard called for an excess of nutrients; but as Haecker fed considerable amounts of concentrates to his experimental animals this fact loses much of its significance, as Kellner and Armsby have shown that the nutrients from concentrates are worth considerably more than those from roughages. Haecker has shown that the nutrients required for the production of one pound of milk increase with the increase in richness of the milk. Another criticism of the Haecker standard is that the cows used were all small animals producing limited amounts of rich milk and therefore the standard is not quite applicable to all animals. This standard is undoubtedly low in nutrients, especially protein. As the amount of work done in the formulating of feeding standards has been relatively limited, the computations made by Morrison perhaps approach the truth more nearly than any other standard of this t}^e which has as yet been put forward. The work of Kellner and Armsby has shown that feeding standards based on total digestible nutrients, regardless of their source, are inaccurate. In other words, no allowance is made for the energy used up in mastication, assimilation and other processes incident to the consumption of the feed. As a concrete example, it may be stated that Armsby has found that timothy hay, which contains 57 per cent as much digestible material as corn meal, is worth, for flesh or fat production, only 37 per cent as much as the corn meal. In the compilation of standards of this tv-pe it was pre- sumed that the maintenance requirements were proportional CRITICISMS 75 to the live weights of the animals. There is a fallacy in this. The amount of heat lost from the animal body through radiation is dependent largely on the area of body surface, and this does not vary directly with the hve weight. Again, animals of the same weight may be in different condition and so perhaps have dissimilar maintenance requirements. Standards Based on Energy Values. — These form the newest type of standards and consequently have been com- puted so as to overcome some of the faults of the earlier ones. The best of the earlier standards were based on digestible nutrients, as already stated; but Kellner found that the digestible nutrients in feeds varied in the amounts of net energy they supplied to the body. He determined experi- mentally the net energy values for production of the digestible portions of the pure nutrients, and then applied these values to the digestible nutrients of the different feeds, and com- pared the computed value of each feed with the actual value as determined by feeding trials. He found that this method of computation was fairly accurate except in the case of feeds high in fiber. In this case an exceptionally large amount of energy was needed for mastication and digestion. The energy required for this purpose was found to be proportional to the amount of crude fiber present; by allowing for this, the computed value was found to be very close to the actual value. Armsby, from his own and Kellner's results, computed a standard for maintenance which was based on true protein and net energy value. This standard allows for variation in the weights of the animals. Eckles then prepared a standard for production on the same basis, and Armsby has since pro- posed a similar one. The chief objection to standards of this class is that the maintenance requirements were determined with beef animals. Perhaps beef and dairy animals do not differ much in their 76 FEEDING STANDARDS maintenance requirements when of the same body weight and in comparable condition, but it would be advisable to have this work checked by experimental data from dairy animals. These standards also fail to attribute any value to the non-protein nitrogen of feeds, which is in some cases of limited value. In addition, the energy values of a large number of feeds have been determined by computation, and further direct experimental work is needed before too much reliance can be placed on standards of this t}^^ The best feeding standard will never furnish anything but a guide for the careful feeder. The individuality of the cow is probably the factor of greatest importance in the feeding of dairy cattle, and standards make no allowance for this. Then again, economy enters in, and the most economical ration may not always be the ration which most closely agrees with the demands of any given standard. There are also various nutritive properties of feeds which are entirely neglected in feeding standards; for example, the content of ash and vitamines and the efficiency of the proteins. Ash or mineral matter is absolutely essential to the well-being of animals, and, though feeds vary greatly in their ability to meet the demands of animals for ash, this point has been entirely neglected in the formulating of feeding standards. Likewise, no attention has been paid to the amounts of the vitamines that are present, and these sub- stances, though essential to the life and growth of animals, are very unevenly distributed in feeds. Moreover, though all proteins are not of equal value for nutritive purposes, feeding standards presume that they are. A SUITABLE STANDARD With such a large number of feeding standards to choose from, the difficulty is to find the one most suited for the calcu- lation of rations for dairy cattle. The modification of the FORMULATING RATIONS 77 Wolff-Lehmann Standard prepared by Morrison is offered in Appendix II for this purpose, as it contains only two units, digestible crude protein and total digestible nutrients, and therefore is easily used. The requirements for the pro- duction of one pound of milk varpng from 2.5 per cent to 7 per cent in butter-fat content are gi^'en, in addition to the maintenance requirements per thousand pounds live weight. FORMULATING RATIONS In formulating rations according to any feeding standard it must be remembered that the results obtained will in most cases be only an approximation, as individual cows of the same live weight and producing abiHty vary greatly in their feed requirements. However, through the use of feeding standards a good idea can be obtained regarding the funda- mental needs of the animals and of the general proportions in which feeds should be mixed in order to provide what the animal needs. In general practice the feeding standard is of little value to the man who thoroughly understands the business of feeding cows, but it has a distinct value in the case of the beginner, as it enables him to grasp more readily the underlying principles of good feeding practice. Before an attempt is made to calculate a ration according to any given feeding standard a few general principles or rules should be learned. In the first place, the ration should be^practical and should contain as large a proportion as pos- sible of h ome-grown feeds, for the dairy cow must be looked on as the market for many feeds that cannot be profitably marketed by any other route. In this connection economy should also be considered. Where purchased feeds have to be used, those which will give the most economical returns must be selected. Variety should be provided in the rntitm , 78 lELDlMi STANDARDS and this will generally be furnished efficiently if two roughages and three or more concentrates are allowed. Every^gw^hmildjec£LY£ alLlhe roughage she will consume, and part of it should be succulent. On the average, dairy cows will consume 25 to 35 pounds of corn silage and 10 to 15 pounds of a legume hay per thousand pounds live weight daily. The roughage of the ration is generally used to provide the maintenance portion of the ration for the animal, while a grain ration is provided over and above this, to be used for pro- ductive purposes. As a general rule, 20 to 30 pounds of dry matter will be required daily per thousand pounds live weight, and about two-thirds of this should be provided by the roughages and one-third by the concentrates. The amount of concentrates fed will depend largely on the milk production. As a general rule, I pound of grain will be needed for each 3 to 4 pounds of milk produced, depending on the amount and richness of the milk. Another method of determining the grain ration is to allow 7 pounds of grain for each pound of butter fat produced. When a ration is calculated in accordance with a feeding standard it is not generally necessary to give great attention to the nutritive ratio, as that will automatically take care of itself; but it may be said that the nutritive ratio required in the ration of a milking cow will generally be between i : 5 and I : 7. As an example of a ration to be made up according to the feeding standard given in Appendix Table II, take the case of a 1200-pound Holstein cow with a daily production of 40 pounds of milk containing 3 per cent of butter fat. The maintenance requirements for this cow can be obtained by proportion from Appendix Table II. The cow is not an exceptionally high producer, and, presuming that the cost of protein in feeds is about normal, she can be given about FORMULATING RATIONS 79 the average requirements for production, or .052 of a pound of digestible crude protein and .271 of a pound of total digesti- ble nutrients per pound of milk produced. Her total daily requirements of nutrients would then be: Digestible Crude Protein, Pounds Total Digestible Nutrients, Pounds For maintenance .84 2.08 9-51 10 . 84 For production Total 2.92 20.35 Now that the requirements of the cow have been found to be 2.92 pounds of digestible crude protein and 20.35 pounds of total digestible nutrients a ration must be found which will fulfill these requirements and at the same time be practical. The nutrients available in the various feeds can be found in Appendix I, which gives the amount of digestible nutrients available in various feeds. For the roughage part of the ration a reasonable allowance would be 35 pounds of corn silage and 12 pounds of alfalfa hay. These feeds will pro\'ide the following nutrients : 35 lbs. corn silage 12 lbs. alfalfa hay Total Digestible Crude Protein, Pounds •39 1.27 Total Digestible Nutrients, Pounds 6. 20 6.19 This leaves 1.26 pounds of digestible crude protein and 7.96 pounds of total digestible nutrients to be furnished by the 80 FEEDING STANDARDS grain ration. A grain mixture can be found, by trial, which will sup])ly this, for instance: Digestible Crude Protein, Pounds Total Digestible Nutrients, Pounds .28 .28 •25 .60 2.10 2 lbs wheat bran 1 . 22 2 lbs linseed oil meal 0. P 1.56 Total 1. 41 8.23 This ration does not exactly coincide with the requirements of the standard, but is sufhciently close to it for practical purposes, as there is a diflference of less than i pound in the amount of total digestible nutrients, and a difference of only .25 of a pound in the digestible crude protein provided by the ration and that called for by the standard. In addition, it contains a good selection of feeds which are palatable, give plenty of variety and are largely home-grown. CHAPTER IX THE BALANCE OF NUTRIENTS In common parlance the balance of nutrients in the ration is considered as referring to the relationship which exists between the digestible crude protein, on the one hand, and the digestible carbohydrate equivalent, on the other hand or, in other words, it is looked on as synonymous with the term nutritive ratio of the ration. It is true that these terms are synonymous but, considered in a broader sense, the term balance of nutrients includes several other factors of great importance, such as the ash content of the ration, the presence or absence of vitamines and the quality of the proteins. Some of the factors which affect the balance of nutrients required by the cow need consideration. To a considerable extent the main classes of nutrients — proteins, carbohydrates and fats — can be used interchange- ably in the animal organism; for example, proteins can be used for the building up of body fat, and the functions of the fat of the ration can be almost completely taken over by the carbohydrates. In spite of this, however, no one nutrient, or group of nutrients, should be used to the exclusion of any other if the best results are desired. Proteins are absolutely essential for the repair of body tis- sues and the formation of the nitrogenous constituents of the fetus and the milk, although most of the other duties per- formed by proteins can be taken over by the carbohydrates and fats. It does not pay, however, to feed just the minimum amount of protein required for these vital processes, as addi- 81 82 THE B.VLAXCE OF NUTRIENTS tional protein appears to have a stimulating elYect on general metabolism and consequently on milk jiroduction. On the other hand, proteins are, as a rule, much more costly than are the other nutrients, and therefore too much protein in the ration will render milk production uneconomical. It is evident, therefore, that a balance must be preserved between the nitrogenous and non-nitrogenous constituents of the ra- tion, and the exact balance to be used must be determined by the requirements of the individual animal and the relative costs of the various nutrients. Similarly, carbohydrates and fats can be used interchange- ably for certain purposes, and yet a proper balance, from the nutritional and economic standpoint, should be maintained between those two classes of nutrients. Feeding standards recognize only the main classes of organic nutrients, no attention being paid to the ash constituents of the feed; and yet the ash is one of the very important ma- terials. One of the main reasons for the neglect to mention ash requirements in feeding standards is that, in general ordinary farm rations contain enough mineral matter to meet the requirements of the dairy cow. Again, very little work has been done to determine the actual ash requirements of farm animals. From what work has been done it may be said that the requirements of dairy cows for some of the more important ash constituents vary widely, but perhaps an average of i ounce of calcium and one-third of an ounce of phosphorus is required for the daily maintenance of a cow weighing looo pounds, while, in addition, i ounce of calcium and one-half ounce of phosphorus will be required for each 20 pounds of milk produced. This demonstrates the small ash requirement of the dairy cow. Although small, it is very important, and when suf- ficient ash for production is not present the cow will draw on her own body for the necessary constituents until her reserve AGE 83 supply becomes exhausted, when she will decline in milk production. If a cow is being fed a ration thai is deficient in one or more of the necessary nutrients she will draw on her own body for the supply of these nutrients necessary for milk production, and when this supply is exhausted she will decrease in pro- duction. Many cows are doing this. They produce milk in fair quantities for a few months after calving, not because their ration is composed of ear corn, timothy hay and corn- stalks, but in spite of it. However, after they have drawn upon their bodies as long as they can for the nutrients neces- sary for milk production they rapidly decline in their yields of milk. When they are dry they again store up in their bodies nutrients to be used for milk production during the next short lactation period. A proper balance of the nutrients — protein, carbohydrate, fat and ash — should be maintained in the ration; but just what that balance should be is rather difficult to state. The balance of nutrients required by a cow depends on a con- siderable number of factors. AGE Young cows are still growing while they are producing milk, and their ration should provide the nutrients required for this growth. Thus, a ration for milking heifers will require more protein and ash, in proportion to the other constituents, than will a ration for older cows, as protein and ash are the constitu- ents specially demanded foi the purposes of growth. SIZE The influence of the size of the cow on the nutritive ratio required in her ration is rather a complicated one. Large cows consume less feed and produce less milk and butter fat 84 THE B.\LANCE OF NUTRIENTS per hundred pounds live weight than do small cows, though the large cows produce most milk and butter fat per hundred pounds of feed consumed. As the small cow produces most milk per hundred pounds hve weight, her maintenance re- quirements constitute a relatively smaller portion of her total feed requirements than is the case with the large cow. Con- sequently the small cow, other things being equal, will re- quire a narrower nutritive ratio in her ration than will the large cow, as relatively less protein is needed in the main- tenance part of the ration than is required in that part of the ration used for productive purposes. One influence which tends to counteract this is the fact that the small cow requires more nutrients per hundred pounds live weight and a wider nutritive ratio in the ration for maintenance than does the large cow, but this variation is not great enough to nulUfy the proposition stated. CONDITION The condition of an animal has an influence on the amount of nutrients required per thousand pounds live weight for maintenance. It was found at the Iowa Station that animals in high condition required more nutrients for maintenance per hundred pounds live weight than they did while in low condi- tion, but the animals in low condition required relatively less protein. In other words, they needed a ration of wide nutritive ratio, this probably being due to an attempt on their part to bring the condition of the body back to normal through the use of carbohydrates and fats for the formation of body fat. Dairy cows should not be kept in low condition, as they will not give maximum production for a long period under such conditions. They should receive a liberal allowance of carbo- hydrates and fats in order that their stores of nutrients may YIELD OF MILK 85 be replenished and they may then be enabled to produce for a longer period. Conversely, animals in high condition should be fed a ration of narrow nutritive ratio in order that the further production of body fat may be prevented as far as possible, since excessive condition is not conducive to maximum milk production. YIELD OF MILK The law of diminishing returns applies to the production of milk, as it does to practically every other form of productive activity. The greater the milk production, the greater will be the amount of nutrients required for the production of each pound of milk; for example, 40 pounds of milk per day will require more than twice as much nutrient material for its production as will 20 pounds per day. It is very probable also that an increase in milk production will call for more than a proportional increase in the amount of protein, as increased activity of the epithelial cells will call for more material for the replacement of kataboHzed protoplasm; consequently, the higher the milk production of a cow is, the narrower will be the nutritive ratio required in the ration. QUALITY OF MILK The richer the milk the greater will be the amount of nutrients required for the production of each pound. The protein content of milk does not increase as rapidly as does the fat content; that is, more milk protein per pound of fat is produced in poor milk than in rich milk. From this it is evident that on the whole the protein requirements for milk production will very probably increase less rapidly than the energy requirements as the milk becomes richer. There will be some increase, however, due to the fact that the epithelial cells of an udder producing 30 pounds of 4 per-cent milk will 86 THE B.\LANCE OF NUTRIENTS do more work than those of an udder producing 30 pounds of 3 per-cent milk. Very probably a narrower nutritive ratio is required in the ration when poor milk is being produced than when rich milk is being secreted. STAGE OF LACTATION As lactation advances more feed will be required to pro- duce 100 pounds of milk than was required in the earlier stages of lactation. This refers to the whole ration, for both maintenance and production. As the amount of milk pro- duced per hundred pounds live weight decreases with advance in lactation, the total amount of feed eaten per hundred pounds of milk produced must increase. It is very probable also that the exact requirements for production alone increase with the advance in lactation, because of the fact that the impetus to milk secretion is decreasing. In the later stages of lactation the cow is usually pregnant; and though work at the Missouri Agricultural Experiment Station has shown that very little feed is required for the growth of the fetus, it is probably best to provide for the cow at this stage a ration with a good supply of protein and ash. At the same time, however, it will be necessary to build up the body reserves of the animal, and the desired increase in weight can usually be obtained by the liberal use of carbohy- drates and fats. Consequently the ration at this stage will have a wider nutritive ratio than that used earlier in the period. INDIVIDUALITY OF THE COW Individual cows vary not only in the total amounts of nutrients, but also in the relative proportions of the various nutrients which they require for the purpose of maintenance and production. Cows of the same weight, producing equal INDIVIDU.\LITY OF THE COW 87 quantities of milk of the same quality, will vary in their requirements. Such variations are due to the "individual- ity" of the animals and cannot be accounted for or controlled. The only solution for this problem is to cater to the needs of the individual cows, as far as possible. CHAPTER X CHARACTERISTICS OF A GOOD RATION A FEEDING standard is but a guide which indicates the approximate amounts of the various nutrients required by an animal. In compounding rations for dairy cattle many factors which are neglected by feeding standards must be taken into consideration, the majority of which are simple and easy to control, yet attention to them will be of great importance in determining the relative economy of milk production. PALATABILITY Though the existence of palatability is seldom questioned, its definition or explanation is by no means simple. The palatability of a feed, though not determined, so far as is known, by the relative amounts of proteins, carbohydrates and fats present, has a decided influence on the economy of milk production. Likewise, though it has no bearing on the inherent digestibihty of the nutrients present, it may prob- ably have an appreciable effect on, the utilization of those nutrients. The palatability of feeds is due to the presence of aromatic substances which give to the ration an aroma and flavor that is pleasing to the cows. The secretion of the digestive juices is to a certain extent stimulated by nervous influences, and there is a probability that palatability and other factors inducing such secretion may thus cause indirectly a change in the amount of material 88 PAI.ATABTLTTY 89 digested. This perhaps holds true to a marked extent only when feeds are very unpalatable. Even if palatability has no influence on digestion, cows must be given feeds that suit their tastes if they are to do their best work, as a cow will not eat all she needs for maximum production if her ration is unpalatable. If feed consumption is not maintained at a high level, milk production cannot be as copious as it should be. Feeds vary widel y in their pala tability and there are also considerable variations in the palatability of dififerent samples of any one feed. Likewise, cows vary in their likes and dis- likes regarding feeds, and individual cows may also vary in their tastes from time to time. It is not possible to rank feeds absolutely according to their palatability, but it may be said that as a general rule the succulent feeds and the leguminous hays are among the most palatable roughages while the cereal grains are perhaps the most palatable concentrates. The by-products used as con- centrates are in some cases not very palatable. There are an exceedingly large number of exceptions to this, however; for example, green^swee ^ clover is_ genemJJx_unpalatable, to animals when first fed, though it is both a succulent and a leguminous feed; rye, though a cereal grain, is not very palatable; while wheat bran and linseed-oil meal, by-products used as concentrates for dairy cattle, are very palatable. The animals find certain feeds unpalatable at first, but begin to like them when they have been fed for some time. This is very frequently true of such feeds as gluten feed and cotton- seed meal, which are generally not relished until the cows have become accustomed to them. Many feeds that are relatively unpalatable can be advantageously disposed of by feeding in a mixture with other concentrates. Care must be taken, how- ever, to include only a limited quantity of the unpalatable feeds in the mixed ration. 90 CHARACTERISTICS OF A GOOD RATION The method of preparation of a feed has some influence on its palatability, cracked corn and ground oats being generally considered more palatable than the whole grains. This can- not be laid down as an absolute rule, however, as a great deal depends on what the animals have been accustomed to. An animal may show a preference for some preparation with which it is familiar and may find a new preparation unpalata- ble for a time, until the animal acquires a taste for the new feed which it may eventually relish more than it did the first preparation. Though ground grains are generally more palatable to milk cows, whole grains are preferred by young calves. The condition of a feed determines its palatability to a large extent. Badly weathered hay and moldy grain are quite unpalatable, and great care must therefore be taken to have all constituents of the ration in good condition if the best results are to be obtained from the feeding operations. The individual peculiarities in the tastes of the cows are not always easy to cope with, but they must be catered to if high production is desired. Feeds that are usually palatable may at times be eaten but sparingly or even absolutely refused by some cows. A pure-bred Holstein cow, Lucy Duchess DeKol, at one time owned by Iowa State College, may be taken as an example. Beginning a few days after freshening, she was fed I pound of ground oats daily in her ration, and in about one month she was receiving 14 pounds of grain daily; of this, 3 pounds were ground oats. It was noticed that she was re- fusing to eat all of her grain, but was trying to get the grain of her neighbor. Her neighbor was receiving a very similar allowance of concentrates but no ground oats. The cow under consideration was decreasing in milk flow, and it was suspected that the presence of the ground oats was rendering her ration unpalatable. The 3 pounds of ground oats was replaced by other feeds and she immediately started to clean PALATABILITY 91 up her grain ration and to increase in production. She evi- dently did not reHsh ground oats at that time, though it is generally considered to be very palatable and she had been consuming it to the extent of 4 pounds per day for some time previous to freshening. Palatability is based to some extent on the needs of the animal, but it is also governed by her past experience. If a cow has been overfed on any feed it is sometimes unpalatable to her for a long time afterwards. A pure-bred Guernsey cow at Iowa State College, Imported Rouge II of the Brickfield, was at one time overfed on gluten feed and for several years she showed a lack of tolerance for it. Later, however, she would consume 2 pounds of it in her daily ration as she had again acquired a taste for it. When a cow appears not to relish her grain allowance it is sometimes difficult to ascertain just which constituent is the cause of the trouble. A suitable method of determining this is to give the cow an opportunity of cleaning up all she wants of her regular grain ration and then offer to her separately small quantities of the individual feeds of which it is com- posed. If a feed offered is palatable she will very probably consume it, whereas if it is unpalatable she will refuse it. Cows will not clean up feeds that are unpalatable to them, and as they very probably do not utilize unpalatable feeds to the greatest advantage even when consumed, it can be seen that unpalatable feeds are unprofitable for two reasons. In some cases cows that arc considered poor feeders and low producers can be rendered more productive by changing their feeds so as to provide them with a more palatable ration. This emphasizes the necessity of individual feeding where large records are aimed at. It shows that lack of care in the selection of the feeds for the ration of the milking herd may result not only in a waste of high-priced feeds, but also in lowered milk production. Upon the ability of the feeder to 92 CHARACTERISTICS OF A GOOD RATION determine the most palatable ration for each of his animals depends the size of the records of the individuals in the herd. VARIETY The dairy cow, unlike the beef animal, is on feed for many successive long periods of time, and as the best production can be obtained only by good feeding, it is necessary that everything possible be done to keep the cow on feed. Palata- bility is an important factor in the feeding of dairy cows, and closely linked with it is variety in the ration. Variety does not mea n a mixture of feeds fro m_ the_ same plant sounre, SucTT^^scorn sila^ge;_corn stov er, corn m^a l gnZTj-nrn gluten feed7but refersto a combin ation of f eeds from distijict sources, such^^corn silage T^Jover h ay, rolled barjey^^wheat bran, ground oats and linseed-oil meal. Frequent or radical changes in the ration are not to be recommended as they tend to throw the cow ofif feed and cause digestive troubles. Rations composed of a limited num- ber of constituents may become unpalatable when fed for a long period, and rations composed of a fair number of dif- ferent feeds are therefore to be recommended. Even such rations, however, occasionally become unpalatable or unsuited to the needs of the cow, but their alteration is an easy matter. The proportions of the various constituents present can be changed, one or more constituents left out, or new constitu- ents added or used to replace constituents already present. In this way the rations can be kept in accord with the needs of the cow for maintenance and production and yet be palatable at all times. Slight changes in the proportions of the con- stituents of a ration will usually do more towards increasing its palatability than will radical changes in the whole ration. For good producing cows two roughages should be pro- vided, preferably corn silage and a legume hay, and as a rule three or four constituents should be included in the grain VARIETY 93 ration. In the corn belt dairy cattle rations too frequently consist of corn and corn products with perhaps one roughage from another source, and comparable conditions are to be found in other regions. Such rations are not economical for milking cows. Variety in the ration, with occasional slight changes in the constituents of the concentrate allowance, will very frequently be all that is needed to keep the ration palatable and the cow producing to her maximum capacity. In other cases, especi- ally with high producers, it will occasionally be found advan- tageous to replace the grain ration with a bran mash. Such a mash is composed largely of wheat bran moistened with warm water, but oil meal and salt may be added. This gives variety, stimulates the appetite, has a laxative, cooling effect on the digestive system, and can be highly recommended when cows become sluggish in their feeding. Recent work has shown that other advantages are to be obtained from variety in the ration. The proteins are built up of amino-acids, but the proteins from different plant sources do not all contain the same amino-acids. As the cow needs a considerable number of amino-acids for the building up of her body and milk proteins and as some of the essential ones are absent or deficient in certain plant proteins, variety in the ration is essential if the cow is to be provided with all the necessary amino-acids. In addition, the vitamines are unevenly distributed in the various feeds and, their presence being essential to the welfare of the am'mal, it is necessary that a ration of varied character be supplied so that the necessary vitamines may be provided in sufficient quantities. The problem of supplying variety in the ration of the dairy cow is not a difficult one, as a general rule, and attention to this factor will be well repaid with additional milk yields and more economical production. 94 CIL\1^\CTER1ST1CS OF A GUOD RATION BULK The dairy cow, like other ruminants, has a large, roomy alimentary tract, especially adapted to the handling of bulky feeds, and she can handle a bulky ration much more efficiently than one of too concentrated a character. There are two main reasons for this. Bulky feeds are easily regurgitated and so are more thoroughly masticated and better prepared for further digestion than are concentrated feeds. In the digest- ive tract of the cow, heavy or concentrated feeds — those that are not light or bulky — tend to form compact masses which resist the action of the digestive fluids and so do not yneld all the nutrients which they are capable of providing. In some cases they may even cause serious digestive disturbances. When plenty of bulky feeds are present in the ration the best digestive action is obtained, as the hay and other bulky materials keep the particles of grain and other concentrated feeds apart and allow them to be thoroughly acted upon by the digestive juices. A good indication of the necessity of a ration of considerable bulk for the dairy cow was obtained at the Iowa Station with two cows on maintenance trials. A ration of uniform compo- sition was fed throughout; when the cows were being main- tained in high condition the average coefhcient of digestibility for the dry matter of the ration was 66.94 per cent, while it was only 59.77 per cent when they were being maintained in low condition. The weight of the ration was 28.6 per cent greater when the animals were in high condition; evidently the increase in the total bulk of the ration allowed the cows to utilize it more completely. As the cow is preeminently a handler of roughages it is usually most economical to allow her to consume as much as possible of the rough feeds grown on the farm. This not only forms a market for home-grown feeds that are cheaply pro- BULK 95 duced and difficult at times to market to advantage, but the presence of the bulky feeds in the ration allows her to utilize the concentrates fed more efficiently than she would other- wise. Practical experience has shown that the best results will be obtained when the roughages, silage and hay, as a rule, provide about two-thirds of the dry matter of the ration and the concentrates about one-third. With high-producing cows the amount of dry matter in the grain fed sometimes exceeds that given as roughage, but long-continued feeding by such methods cannot be endorsed, as it is an enormous strain on the digestive system of the cow and a general collapse in digestive powers and producing ability will result. In the cases where a heavy grain ration is being fed, and even frequently when the grain allowance is not so Hberal, it is advisable to have some bulky constituents in the grain ra- tion in addition to the roughages. This can be suppHed in many sections by such feeds as corn-and-cob meal, wheat bran and ground oats. Cottonseed hulls are occasionally used for this purpose in some locaHties. The particles of cob present in corn-and-cob meal have Httle, if any, nutritive value, but their mere physical presence keeps the particles of corn apart, thus allowing more thorough digestion and utilization of the nutrients in the particles of corn. The action of the cob is almost entirely mechanical, but it is of such a nature that it renders corn-and-cob meal of about equal value to corn meal, on the basis of weight, for feeding purposes with dairy cows when other bulky constituents are lacking in the grain ration. Where such light and bulky feeds as ground oats and wheat bran arc too high-priced to give economical returns when fed to dairy cattle, a good method of obtaining bulk in the grain ration of high-producing cows is by the addition oi alfalfa or clover hay which has been cut into quarter-inch lengths. The hay should be cut daily so that it will remain 96 CHARACTERISTIC'S OF A GOOD RATION fresh. After moistening with steam or warm water, just sufficient to soften the stems, it is mixed with the concentrates. A very good indication of the relative bulk of concentrated feeds can be obtained from a slu(l\- of their weights per quart. An idea of the wide variations which occur in these weights can be obtained when it is noted that corn and cottonseed meal each weigh 1.75 pounds per quart, while a quart of wheat bran weighs only .55 pound or less than one- third as much. SUCCULENCE Succulent feeds ha\'e a \ery beneficial effect on milking cows and are essential to the most economical production of milk. The benefits to be derived from succulent feeds are due to a considerable extent to the fact that they render the ration palatable, are laxative in nature and provide part of the large amount of water required by high-producing cows. Good pasture grass is the best succulence for dairy cattle, and in the early part of summer it will, as a rule, provide all the succulent feed they require. In the later part of summer, when the pastures in many sections begin to dry up, soiling crops or silage should be used to provide additional succulence. In winter, silage forms the most economical succulence, though it can sometimes be advantageously supplemented with roots or dried beet pulp, which is soaked before feeding. Some form of succulent feed should be included in the ration of the dairy cow throughout the year. EFFECT UPON THE SYSTEM To work profitably, every cow must at all times be in perfect health; consequently the feeds selected must be such as will keep her digestive tract in its best working condition and also maintain her in general good health. The cow will do her best work when her ration is laxative in character, and EFFECT UPON THE PRODUCTS 97 SO the ration as a whole must be one that tends to counteract constipation. Succulent feeds, as already mentioned, have a beneficial effect on the digestive system and general condition of the cow. Alfalfa and clover hays are also shghtly laxative in effect and for this, as well as other reasons, are to be preferred to such feeds as timothy hay, oat straw and corn stover, which are constipating in action. Feeds that are moldy or in other ways spoiled tend to cause digestive troubles. In addition, they may cause de- rangement of health or may even be absolutely toxic, and so should be avoided. The dangers of moldy feeds, however, are not as great with cattle as with horses. Some feeds have spccihc effects on the digestion and general health of the cows; in compounding a ration for a dairy animal it is necessary, therefore, to see that the bad effects of any of the individual constituents of the ration are counterbalanced by the good effects of other feeds. Cottonseed meal has a constipating effect, and when fed in too large quantities may even become toxic. It should never be fed to cows near the end of pregnancy nor to calves under weaning age. Feeds such as wheat bran and oil meal have a laxative and coohng effect and should, as a rule, be fed when constipating con- stituents are included in the ration. They are especially valuable where no succulent roughage is available. Care m.ust always be taken in compounding a ration to see that it is laxative in character and that no feeds which might produce undesirable results are fed in large amounts. EFFECT UPON THE PRODUCTS Milk and butter fat are the marketable products of the dairy farm, and care must be taken to avoid any deleterious effects which might be produced on those materials by the feed given to the cows. 98 CHARACTERISTICS OF A GOOD RATION It has been found that, as a rule, the feed does not have any influence on the flavor of milk, provided the feeding is care- fully done, even though it has frequently been stated thai silage imparts a disagreeable flavor to milk. If the feeding be done carelessly this is true, but if proper methods of feeding be pursued and proper precautions be taken to prevent the contamination of the milk, no deleterious effect will result. The same appHes to rutabagas, cabbage and similar feeds. If silage or roots are fed just before milking, or unused feed is allowed to remain in the mangers, the milk may have a dis- agreeeable odor, especially if it is not removed from the barn immediately after milking. Garlic and other weeds will impart a disagreeable odor to the milk when they are consumed by the cows. This is due to volatile substances present, which are absorbed from the ahmentary tract, carried to the udder by the blood and eliminated in the milk. Such substances do not affect the flavor or odor of milk for any considerable length of time after they have been eaten. Certain feeds influence, to a limited extent, the chemical and physical characteristics, and consequently the consistency, of butter. Linseed-oil meal, peanut meal and gluten products have a tendency to produce a soft, salvy butter of inferior flavor, while cottonseed meal renders the butter hard and tallowy. These feeds do not produce marked effects unless fed in too large quantities, and by properly balancing the constituents of the ration such influences can be minimized. The feeding of cottonseed meal in the summertime is often advisable, as the butter produced at this season is generally soft and cottonseed tends to make it firmer. PART IV THE FEEDING STUFFS CHAPTER XI SILAGE The ensiling of crops is not new, but the present-day silo is of comparatively recent origin. The silo makes possible the complete utilization of a large amount of succulent forage that would otherwise be wasted or only partially used, de- creases the labor of winter feeding, makes available a supply of good feed at seasons when it would otherwise be scarce, acts as a storehouse in which excess feed from one year can be carried over to another, and ultimately increases the live- stock-carrying capacity of the farms. The increase in the number of silos within the last decade has been remarkable, but a realization of their true value will further augment their numbers. CORN SILAGE Corn silage is an essential feed on all dairy farms in the corn belt. Without it the largest and most economical milk production cannot be obtained. Corn is the best silage crop for several reasons: it gives good yields, packs well in the silo, is rich in starch and other non-saccharine carbohydrates, thus insuring silage with a moderate acidity, and has a relatively low protein content, thus reducing to a minimum the danger of putrefactive changes. The main acids present in silage are lactic and acetic, and they tend to impart to it a pleasant aromatic odor, thus increasing its palatability. 101 102 SILAGE The best corn to grow for silage depends on the locality, and the best silage is made from corn which will practically mature where it is grown. Rank southern corn, while yield- ing more in total weight of green feed per acre, does not generally produce more when considered on a dry-matter basis. It does not make as palatable nor as desirable a silage as do some of the less luxuriant tj-pes. While practical men are not all agreed as to the best time to cut corn for silage, the general practice is to do it soon after the corn begins to dent and the lower leaves begin to dry up. In the northern sections the aim is to cut the corn just before frost, without much regard to its maturity. The degree of ripeness at which the crop is cut has a great influence on the yield and quality of silage produced. If the ensiling is done too early the maximum yield of nutrients will not be obtained and, owing to the large amount of water and soluble substances present, the fermentation will be excessive, much valuable feeding material will be lost, a poor quality of silage will result and the large amount of water present may even cause the silo to leak. If the cutting is delayed too long the yield of dry matter will be at a maximum, but owing to the maturity of the corn there will be a high fiber content and too little moisture to insure good packing; large amounts of air will be present, and the contents of the silo will become moldy and perhaps rot, unless water is added at the time of filling. Moldy silage is not only undesirable but sometimes even dangerous to stock, although this danger is not so great with cattle as with horses. The yield of corn silage per acre is variable, but it may generally be assumed that about 1 ton of silage can be expected for each 5 bushels of corn that could be obtained. The following figures adapted from "The Soft Corn Pre- dicament," by Evvard, of the Iowa Agricultural Experiment Station, illustrate well the facts mentioned : CORN SILAGE 103 TALBE XII Percentage Yield of Nutrients from an Acre of Corn at Different Stages of Growth Stage of Growth Dry Matter, Per Cent Crude Protein, Per Cent Nitrogen- Free Extract, Per Cent Crude Fiber, Per Cent lOO 95 86 66 ICO 95 82 79 I GO 96 86 61 Well dented In the glaze In the milk 92 88 78 That the use of the silo makes possible the most efficient harvesting of the corn crop is shown by results from the Wis- consin Agricultural Experiment Station. During a period of four years it was found that when the corn crop was dried in the shock there was an average loss of 23.8 per cent of the dry matter and 24.3 per cent of the crude protein, whereas when the corn was made into ensilage the respective losses were 15.6 per cent and 16.8 per cent. This shows a con- siderable conservation of the valuable food nutrients. Then again, when the crop has been put in the silo all of it will be consumed by the animals, but when the corn has been shocked the stock will refuse a large part of it. Though good succulent corn is to be preferred for the making of silage, fairly satisfactory feed can be made in the silo when this is not obtainable; by this means a corn crop which has been damaged by drought or frost, and which otherwise would be wasted to a large extent, can be made into a valuable forage. Such material is not necessarily poor or dangerous as a feed. It contains the same amount of nutrients as it did immediately before it was damaged, though, of course, less than if it had been allowed to come to the proper stage of development. If it is ensiled as soon as 104 SILAGE possbile after it is damaged it will come out of the silo in good condition. If it has been allowed to dry out, however, water should be added as it is being put into the silo, as this will aid in the packing process and give the necessary succulence. Corn fodder that has been dried in the shock can also be made into good silage if plenty of water is added to moisten it. Though not quite as palatable as the silage made from the fresh, green forage, it gives good results and will be more thoroughly utilized than would dry fodder. Similarly, corn stover can be rendered more valuable as a feed by being put in the silo, though, of course, the absence of the ears lowers its feeding value. The amount of water that should be added in the ensihng of fodder or stover varies, but it has been found that as a rule about i pound of water will be required for each pound of dry forage. According to recent Illinois Agricultuiai Experiment Station results, shghtly less water gives a more palatable silage. The quahty of the silage is largely affected by the amount of water added. More water than is actually required does not harm the feed, though it makes it heavier to handle without any apparent benefit. Good results have been obtained from the ensiling of fodder at the Missouri Agricultural Experiment Station and other Agricultural Experiment Stations and by practical dairymen, and if future work confirms this it may become a common practice to fill silos twice or oftener during the year. A conservative estimate fixes the value of the silage at from lo per cent to 20 per cent over the equivalent dry fodder, though some put it much higher. Sometimes when silos are filled at the usual time the corn is husked, but this is not to be rectmimended. At the Vermont Agricultural Experiment Station it was found that the yield of 1 1 acres treated by this method was required to produce silage of the same value as that from an acre of unhusked CORN SILAGE 103 corn. Where the corn has been husked, a heavier grain ration must be fed; there is, therefore, no advantage in husking and then ensihng the crop. Poor silage, as a rule, results from one of two causes. First, poor packing of silage, with plenty of moisture present results in the entrance of air and rotting, while in the second place silage that is too dry will not pack well and as a con- sequence it will become moldy. Good packing at filling time directly influences the quality of the silage. Great variations are to be found in the estimates given as to the cost of producing a ton of silage. The cost varies greatly with individual cases, depending largely on the size of crop obtained and the cost of labor. The cost of producing silage is sometimes figured on the basis of the corn it contains — the market value of the corn being used. This really gives not the cost of production of the silage, but the sum that could have been obtained by selling the corn at the elevator in preference to putting it in the silo. This latter method of determining the value of the silage can frequently be used advantageously if some allowance is made for the fodder contained. The increase in the corn-canning industry has resulted in the production of a large amount of cannery refuse which is frequently allowed to go to waste, but which can be satis- factorily used as silage. At some canneries this refuse is put in silos while at others it is simply piled up. The greatest conservation is obtained where the silo is used, but even the piled-up waste can provide a large amount of good feed, though the outside material will be spoiled. Where the spoiled ears and the cobs are not put in with the remainder of the waste products from the sweet-corn cannery, the refuse has a fair feeding value. It was found at the Iowa Agricul- tural Experiment Station that i ton of this material, with the addition of 5 bushels of corn, had a value about equivalent to 106 STLAGE that of I ton of good corn silage. Where the spoiled ears that cannot be used for canning are put in with the rest of the waste material, a silage of somewhat higher feeding value will be obtained. This indicates that, by the proper utiliza- tion of all the cannery refuse by means of the silo, a very valuable addition to the supply of succulent forage for winter feeding would be obtained in many sections. The value of corn silage as a forage depends largely on its succulence, bulk, palatability and the beneficial effect it has on the digestive tract of the animal. In effect it is laxative and coohng. These are the essential characteristics of a good ration for a dairy cow and they make silage an excellent feed for milk production. In addition, silage from unhusked corn contains about 5 bushels of grain per ton. Silage should be fed to all classes of dairy cattle. The only precautions that have to be taken are in the feeding of the bull and the young calves. Too much silage causes the bull to become sluggish, awkward and slow at breeding. How- ever, a limited amount is desirable. Silage is not desirable for young calves as it ferments readily and thus may cause digestive disturbances. Silage should be supplemented not only with concentrates but also with a legume hay. Cirowing stock and milk cows need all the silage they will consume, in addition to their hay and grain. Milk cows, as a rule, take 2^ to 3^ pounds of silage per hundred pounds live weight per day. When the cows are turned out to pasture in the spring the milk yield invariably increases; this is due largely to the palatable, succulent nature of the pasture. This initial rise is not a full measure of the value of pasture, however, as it puts the cows in condition for continued milk production. The feeding of silage in winter renders available many of the advantages of pasture, as the essential characteristics of the two are similar. CORN STLAGE 107 Silage, though of greater value in winter, can be used to considerable advantage in summer when the pasture is short and dry. The feeding of silage in the barn, during the hot, dry weather of summer, is an excellent method of supplement- ing scant pasture. The feeding of silage, though not a difficult matter, should be done with care, or trouble may arise. The silo should be of such a diameter that sufficient feed can be taken out each day to prevent decomposition of the top layer. This is especially true in the summer, and if a silo is erected for sum- mer use only, it should be of smaller diameter than the winter silo. In winter the silage will keep well if at least 2 inches per day are removed for feeding purposes, but in summer it must be removed twice as rapidly. In general, the winter silage-feeding period averages about two hundred and twenty- five days in duration, and as 2 inches is the smallest depth of silage that should be removed per day, the total depth of the silage in the silos should be at least 36 to 38 feet at the beginning of the winter feeding of silage. At one time it was thought that good milk could not be produced when silage was fed, but this is incorrect. Milk will rapidly take on a silage odor if it is given the opportunity. If the silos are shut off from the barn, the silage fed after milking, the amount limited to what will be cleaned up in a short time, and the milk removed from the barn as soon as it is drawn, there is no danger of having a silage odor in milk. Bad odors of any kind in milk are, as a rule, due to careless- ness. A test conducted by the Illinois Agricultural Experi- ment Station regarding the flavor of milk from silage-fed and non-silage-fed cows gave results very favorable to the milk from the cows that had received silage. Out of three hundred and seventy-two people to whom the milk samples were submitted 60 per cent preferred the milk from the silage-fed cows, 2q per cent preferred the milk lOS SILAGE from the non-silage-fed cows, and ii per cent expressed no preference. Even at the present time it is sometimes said that silage causes the teeth of the cows to decay, brings about digestive troubles and may induce abortion. These statements are incorrect. Silage does not cause teeth to decay, and unless it is badly molded or decayed or suddenly fed in too large quantities, it will not cause digestive troubles. The only wav in which silage could induce abortion would be as a result of some of the improper feeding methods just mentioned. OTHER SILAGE CROPS Corn is the paramount silage crop on account of its adapta- biUty for this use and the wide area over which it is grown. Other crops are used for silage to a limited extent, in some cases where corn cannot be successfully gro^^^l and in others where attempts have been made to utilize by-products that would otherwise be wasted. Non-Leguminous. — Of the non-leguminous crops used for silage, the sorghums are perhaps the most important; both the sweet and grain sorghums are used for this purpose. They are of the greatest value in the drier sections of the country, though of httle importance in the corn belt. Under such conditions they give good fields and provide a very palatable silage which is somewhat below corn silage in feeding value. At one time it was thought that the sorghums would give a silage of too great acidity, but this is incorrect. Kafir corn and amber cane appear to be the only two sorghum silages which have been directly compared and the former was of somewhat higher feeding value. Some work has been done in the west on the use of sun- flowers for silage, and although fair results have been obtained, the feed is not as palatable nor as valuable for milk production as is corn silage. To make the best silage, the sunflowers OTHER SILAGE CROPS ■ 109 must be cut when about one-third of the crop is in bloom and chopped finely to insure proper packing. The silage made in this way is perhaps of about the same value as that made from immature corn. The possible future for sunflower silage lies in some of the regions where corn cannot be successfully grown. The lesser cereals, such as oats and rye. have been used to some extent for silage, but they do not provide as valuable a forage as does corn. The yields are small and the crops must be cut early to prevent the presence of too large an amount of fiber. In addition, good packing is necessary to prevent large amounts of air from lodging in the hollow stalks and resulting in undesirable fermentations. Similarly, grass crops are oc- casionally used for silage where the locality or season is too damp to render the making of good hay possible. Such practices are quite infrequent in this country. A few materials of relatively high water content, such as beet pulp, beet tops, apple pomace and prickly pear, are occasionally used for silage purposes. Though the silo renders the utilization of these materials for feeding purposes possible, they do not furnish the best quality of silage. This is largely due to the great amount of water present and the difficulty of preventing deleterious fermentations. The use of such materials for silage must always be limited though at times it may be recommended as a conservation process. Leguminous. — Many attempts have been made to ensile such leguminous crops as clover, alfalfa, soybeans and cow- peas, but the results have not been very satisfactory. The presence of a considerable amount of protein gives a good basis for the occurrence of a large amount of putrefaction, while the absence of a sufficient quantity of soluble carbohy- drates limits the formation of the organic acids which exert a preservative effect on corn silage. There consequently appears to be little future for the use of legumes as silage 110 SI L AGE crops, though it is the practice in some sections to use the pea-vine waste from pea canneries for silage purposes. This is simply a conservation process which renders possible the use of feed which would otherwise be wasted. Mixed. — It is recognized that crops, such as corn and the sorghums, which contain a fair amount of soluble carbohy- drates, are most easily preserved as silage. One of their disadvantages, however, is that they do not contain quite as much protein as might be desirable. Consequently, at- tempts have been made to combine leguminous crops which are not easily preserved with some of the non-legumes and so get a silage of good keeping quaUty and fair protein content. Corn has been ensiled with both soybeans and cowpeas, and satisfactory results have been obtained in many cases, though occasionally less favorable reports are given. More information on tliis problem is needed from both the practical and the experimental standpoints. Sometimes the crops are grown in mixture; sometimes they are grown separateh' and then mLxed when the silo is being filled. The sorghums have been also used along with the legumes in much the same way as has corn. Another mixed crop occasionally used for silage, but with only fair success, is oats and field peas in mixture. CHAPTER XII SOILING CROPS Soiling crops make excellent feeds for supplementing pas- ture in summer. With the aid of soiling crops the area of pasture needed for the dairy herd can be reduced, or more animals can be kept, and the cost of milk production con- sequently lowered. The other advantages of soiling crops are similar to those resulting from the feeding of silage during summer, with the addition of variety. A very wide variety of crops can be used for soiling pur- poses, though the regions in which some of them can be used are quite limited. It is important, in outlining a soiling system, that only the feeds specially adapted for growth in the locality under consideration be selected, as otherwise cer- tain failure will result. Care should be taken to include in the system as large a number of legumes as possible. LEGUMINOUS The leguminous crops suited for soiling are adapted to a fairly wide range of territory and, though they are not noted for phenomenal yields, they are especially valuable for the protein which they provide. The use of leguminous soiling crops tends to reduce the amount of protein concentrates needed in summer, and though in some cases not quite palat- able at first, they are generally to be recommended. Alfalfa. — This is undoubtedly the most valuable soihng crop among the legumes, since the various cuttings may all be 111 112 SOTLTNG CROPS Utilized as soiling. Alfalfa may be said to owe its importance as a summer forage crop to its high nutritive value, being especially rich in ash and protein; to its palatability ; to its large total yield where successfully grown; to its drought re- sistance and to its long life and consequent small cost of seeding. Alfalfa may be used to furnish green feed during the entire season if a sufficient acreage be available, as the various cuttings may be so timed as to keep the supply of succulent forage continuous. The period through which any one cutting is suitable is limited, however, as too early cutting decreases the yield, while delayed cutting will result not only in highly fibrous material but also in a decrease in the yield of the succeeding crop. Consequently, in herds of small or medium size, it is not possible to utilize large areas of alfalfa for soiling. Generally the first cutting of alfalfa is very useful in the early part of the soiling season when other succulent feeds are not readily available. The later cuttings can also be used to advantage. The yields secured vary from lo to 20 tons per acre. Green alfalfa stimulates milk secretion to a consider- able degree, but the main drawback to its use is that, though it is fairly palatable, cows will not consume as much of it as they will of some other soilages. This is due, to a considerable extent, to the fact that most of the alfalfa used for soiling is fed during the early part of summer when pastures are still quite good. Clovers. — The clovers are extensively grown in the United States, but in spite of this fact they are not as valuable for soilage as alfalfa. While red clover is more widely grown in the United States than any other legume, it does not fill an important place in soiling systems. It does not compare favorably with alfalfa in yield, although from 8 to 1 2 tons of green feed per acre are usually secured. It can be fed for only LEGUMINOUS 113 a very short period as the stems quickly become woody. For soiling purposes it should be cut just before the blossoms appear, as at this period it yields more protein and less fiber per acre than at any other time. Bloating seldom results from the use of red clover as a soilage, although it is advisable that the green feed be neither wet nor badly wilted when used. One disadvantage of red clover as a soiling crop is that when grown alone it frequently lodges. The second crop can be used for soiling, though better adapted for hay, pasture or seed production. Mammoth red clover is larger and coarser than red clover and, though it gives heavier yields, is not quite so suitable for soiUng. It is also less palatable. Alsike clover is adapted primarily to low, wet land, and though it tends to lodge and does not give quite as large yields as red clover, it is an excel- lent soiling crop. It produces a fine leafy forage, and since it is very palatable, cows will consume large quantities of it; it also stimulates milk production to a considerable degree. Crimson clover, though grown to a considerable extent in the south, is not a first-class soiling crop. Sweet Clover. — The value of this plant for soiling purposes is in dispute, many reporting that it is not entirely satisfac- tory while others have lavished praise upon it. Yields may vary from 8 to 15 tons per acre, but the stems rapidly become woody and the feeding period is relatively short. It tends to be unpalatable to animals when fed in the green state, but they usually become accustomed to it and consume it with apparent relish, especially if the feeding of it is started early, before the bitter principle, cumarin, has developed to any considerable extent. The annual variety is perhaps of less value than the biennial. Peas. — The Canadian field pea is an annual legume not very suitable as a soiling crop when grown alone. The yields arc usually less than 7 tons per acre, and as the stems are 114 SOILING CROPS slender the crop tends to lodge. The Canadian field pea is useful in mixtures. In the case of the flat pea it is frequently difficult to secure a stand, and as the green forage is unpalata- ble it is not used for soiling purposes to any considerable extent. Vetches. — Two vetches, the common and the hairy, have been used for soiling purposes, but the common vetch is not very palatable and cannot be recommended. The hairy, or winter, vetch is a very slender-stemmed winter annual, and though it yields from lo to 12 tons of green feed per acre it tends to lodge and is very difficult to handle. It is fairly palatable, remarkably free from disease and insect pests and resists low temperatures and droughts, but the high price of seed frequently prevents its use for soiling purposes. Though trouble may be experienced in obtaining a stand where the crop has not been grown before, yet it will give satisfactory results under ditficult conditions and thrives well on sandy soils. Cowpeas. — Cowpeas are best suited to the southern states and are matured successfully in the northern sections only when the small early varieties are grown, and then the yield is small. While it is a larger-stemmed plant than the Cana- dian field pea, it is not self-supporting when the crop is heavy, and is therefore best suited for mixtures. Cowpeas furnish palatable forage during the latter part of the soiling season. Average yields of 6 to 10 tons per acre may be expected. Soybeans. — This crop is well adapted to a wide range of conditions. In feeding value, green soybean forage com- pares well with green alfalfa, and the plant is more resistant to heat and drought. Where clover kills out, soybeans may be used as a catch crop, although, where the ground is poor good cultivation is necessary to keep down the weeds. Soy- beans, which are becoming more widely used annually, mature for soiling during the latter part of the summer and will ordinarily yield 5 to 7 tons of green feed per acre. For NON-LEGUMINOUS 115 the best quality of soiling the seeding should be heavy, if bushels per acre being recommended. NON-LEGUMINOUS Com. — Corn, being the main crop in a very large section of the United States, must be recognized as a possible soilage. Dent corn is used as soiling to some extent, returns rather a large yield and is quite palatable. It is difficult to handle and feed, however, and is not cleaned up well by the cows. Green corn cannot be safely fed until rather late in the sum- mer, as it tends to cause digestive troubles, but during the later part of the season it may be fed until ready to cut for silage. It should be borne in mind that feeding green corn does not give the cow very much of a variety as compared to the winter ration, if this includes corn silage. Flint corn is adapted primarily to the northern part of the corn belt. It does not return as large a yield as dent corn though it is equally palatable. Sweet Corn.— Sweet corn is the most palatable of the corns, and is used for soiUng to a greater extent than the other varieties. In yield it ranks close to dent corn, and it is more satisfactory, as it stays green longer and the leaves do not fall so readily. Neither does it become so coarse nor is it so difficult to feed as is dent corn. It furnishes very good soilage when the ears have been removed previous to feeding, a prac- tice followed near canning factories. The length of the feed- ing period will depend upon the number of varieties grown and may extend throughout a considerable part of the late summer. The use of green sweet-corn stover can be highly recommended for soiling wherever the crop is grown to supply canning factories. Lesser Cereals. — The lesser cereals are grown over a very wide range of territory and are used to some extent for soiling. They are not of great importance for this purpose except when 116 SOILING CROPS grown in mixture with some legume. Oats do not make a very successful crop when grown alone, although they are highly recommended for mixtures. The yield secured will average about 7 tons per acre, and if cut early it makes quite a palatable feed. The main drawback to its use is that it ripens rapidly and so has not a long period of usefulness Barley is very similar to oats as a soiling crop and cannot be recommended except in mixture, especially as it tends to ripen even earher than oats. Winter wheat has been used to a considerable extent as an early crop in spite of the fact that it seldom yields over 8 tons of green feed per acre. It matures early, however, and where only Hmited pasture is available its use may be neces- sitated by the lack of other early green feeds. Winter rye has been used for soiHng more than any other of the lesser cereals. It gives fair yields, averaging perhaps slightly more than wheat; it is only fair in palatabihty but can be used very early in the season for soilage purposes. It is. however, perhaps more valuable for early pasture than for soilage. Under some conditions green rye forage has been known to impart a peculiar and disagreeable flavor to milk. Millets. — The. millets, though perhaps not of primary im- portance for soiling purposes, have been used fairly exten- sively. The foxtail millets include common, German, Hun- garian and many other varieties. These varieties have been used successfully for soiling, their main value being due to the fact that they mature late in the fall when the number of other crops available is limited. They can be used until the time of frost. Yields vary considerably, but 10 to 14 tons of green millet forage per acre is not uncommon. The foxtail millets vary considerably in value for soiHng purposes. The common millet is fine-stemmed and leafy, giving a good quality of forage, while German millet is coarse and relatively unpalatable to stock. NON-LEGUMINOUS 117 Millet matures rathei rapidly, and under the most favor- able conditions is ready for harvesting forty to fifty days after seeding. To secure a good quality of forage, hberal seeding is advisable, 2 to 4 pecks per acre being generally recommended. Japanese Barnyard millet, or Billion Dollar grass, is coarser than any of the foxtail millets. When cut before the plant heads out, it is fairly palatable, but as the crop matures it becomes woody and unpalatable. Thick seeding should be practiced to insure a fine-stemmed, palatable forage. Pearl millet, or cat-tail millet, is low in feeding value and cannot be recommended for use as a soiling crop. Sudan Grass. — This crop is more especially suited to the arid and semi-arid regions, although it is being grown to some extent under quite different conditions and with fair success. It gives rather large yields of feed but dries out very rapidly and is apt to become fibrous and unpalatable when mature, a fact which minimizes its possible value as a soiling crop. Under some conditions it may be used successfully, but generally other crops will be more profitable for soiling purposes. Amber Cane. — Amber cane is one of the most valuable crops for soihng purposes. The yield is large, and under average conditions 10 to 16 tons of green feed per acre can be obtained. On the Iowa State College Dairy Farm the aver- age yield over a period of seven years was 12 tons per acre — the highest yield for any soiling crop used on the farm. The average cost of production was also lower than that of any other crop used for soiling purposes. In addition to yielding heavily at low cost it is extremely palatable, and cows will consume large quantities of it — 70 pounds per cow per day being generally a fair allowance. To insure a fine-stemmed forage, seeding should be at the rate of at least 70 pounds per acre, while 90 pounds will give even 118 SOILING CROPS better results. The crop is sometimes difficult to handle, but by the use of a small grain hinder this trouble can be largely avoided. Other Sorghums. — A few other sorghums, such as orange cane, kalir corn, feterita and milo, are occasionally used for soiling, but they are best adapted for arid conditions and cannot be generally recommended. It has been proved that many of the sorghums, including Sudan grass, may at times be poisonous. The poisonous effects are generally produced in the second crop but may occur in the hrst. Poisoning does not occur unless the crop has been stunted by frost, drought or other causes. The poisonous principle is prussic acid, which is produced very soon after the crop is stunted. Sorghum silage that has been in the silo for a week or two and dry sorghum fodder do not produce poisoning as the prussic acid that may have been in them if they were stunted has been destroyed. Sorghum poisoning has perhaps received too much publicity as out of ten thousand men raising Sudan grass pasture in Kansas in 1919 only three reported the loss of a few animals from this cause. No cases of poisoning have ever been re- ported after the animals had finished their first day on a Sudan grass pasture. The risks of poisoning are evidently obviated if the animals have become accustomed to the sorghum forage before it is damaged. This has been shown at the Iowa Agricultural Experiment Station by continuing to use amber cane for a soiling crop for some time after it was frosted and by the fact that cows were successfully kept on a Sudan grass pasture at the Kansas Experiment Station for some time after the forage was frosted. Grasses. — Such crops as timothy, red- top, either alone or in mixture, brome and orchard grass, are occasionally used for soiling purposes, but they cannot be generally recommended, as they do not give large enough yields to be profitable, are MIXED 119 unpalatable, and contain very little protein, though the presence of clover in a mLxed grass crop will add to its value. They can be more profitably used for pasture or hay. Rape. — Though rape is used for soiHng, it is not adapted to this purpose, the yields obtained arc low, it may cause bloat and, in addition, it imparts a disagreeable flavor to milk at times. MIXED Mixtures of leguminous and non-leguminous forage crops have been widely grown for soiling purposes. Many of these mixtures have much to recommend them, since they possess several of the valuable characteristics of each of the other two groups. Their value depends upon the suitabiUty of the individual crops for the locality in which they are grown and upon their adaptability for growth in mixtures. The mixed crops studied here will be grouped according to the legumes they contain. Pea Mixtures. — Though they are not very successful when grown alone, Canadian field peas are valuable when grown in a mixture for soilage purposes. A mixture of oats and Canadian field peas is one of the most valuable of early soiling crops. Both are well adapted to a wide range of territory, and when grown together they give moderately large yields of very palatable feed. Yields of from 5 to 10 tons of green feed per acre have been secured quite frequently. This crop is of great ser\ace in the early part of the season. The later sowings are not so satisfactory, as the oats ripen too rapidly and give an unpalatable feed. Best results are ob- tained if the feed is cut when the oats are in the milk and the peas have just filled the pods. Owing to the fact that oats mature more rapidly than do peas it is good practice to drill the peas about a week before the oats are sown. A satis- factory stand can be obtained by seeding i| bushels each of oats and peas. The amount of soiling consumed at the time 120 SOILING CROPS oats and peas are available is usually not large, as pasture is fairly plentiful at that time, but in spite of this cows will consume from 40 to 60 pounds of the green feed daily. Cana- dian field peas give less satisfactory results when grown in mixture with barley than they do with oats. This is due to the fact that barley ripens more rapidly than oats. Vetch Mixtures. — The vetch is more suitable in mixture than when grown alone, as its stems are not self-supporting. Oats and vetch have at times been recommended in place of oats and Canadian field peas, but the yields are generally smaller and the high price of vetch seed generally prohibits its use. Winter rye and hairy vetch have given good results in mixture for soiling. The vetch increases the yield, protein content and palatability of the forage. This mixture will provide green feed earlier in the spring than will any other soiling crop containing a legume, and where no pasture is available its use may be advisable where the cost of seeding is not prohibitive. Cowpea Mixtures. — Cowpeas have to some extent been grown in mixture for soiling purposes, especially in the south, where good yields have been obtained. On the whole, how- ever, cowpeas cannot be generally advocated for growth with such crops as corn and amber cane. The cowpeas do add to the protein content of the feed, but where the other crop is sown thickly, a practice which must be followed for success with soiling, the cowpeas are smothered. Thus the extra seeding costs do not result in any appreciable increase in yield. Soybean Mixtures. — Soybeans have been grown in mix- tures very similar to those used with cowpeas and they do rather better. On the whole, however, they cannot be recom- mended in mixture as they give results not far different from those of the cowpeas. CHAPTER XIII MISCELLANEOUS SUCCULENT ROUGHAGES Though silage and soiling crops play an important role in inducing economical milk production, other succulent forages remain to be considered. The majority of these are of but little importance, but one, pasture, is deserving of consider- ably more attention than it generally receives. PASTURE Good succulent pasture is the feed, par excellence, for the dairy cow. The forage it provides is not only bulky, succulent and palatable, but it contains the nutrients required by the dairy cow in about the correct proportions. As a general rule, it may be said that no matter what the conditions are some pasture should always be provided for the dairy herd as the change from barn feeding is very beneficial as far as milk production is concerned, and the exercise the cows receive when at pasture keeps them in good working condition. When the cows are turned to pasture in spring the milk flow is maintained at a higher level than it would otherwise be, but the benefits of the pasturing season are also noticeable during the remainder of the lactation period. The pasture season varies considerably in length in various sections, and the pastures themselves also vary greatly in quahty, but it may be safely said that in the early part of the pasture season no additional roughage will be needed. It is well also to cut down, and in most cases entirely eliminate, 121 122 MISCELI.AXEOUS SUCCUT.ENT ROUGHAOES the grain ration during the early part of the season, except in the case of the heaviest producers. This cools and rests the digestive tract and puts the cow in better shape to handle concentrates when it again becomes necessary to feed them. In most sections of the country, if pasture is used through- out the summer without some supplementary succulence, such as silage or soiling during the later and drier part of the season, from i^ to 2^ acres of pasture per cow will be required. Even this will not give the best results, however, and it is generally better to feed some additional succulence. In this way the area required to maintain a cow will be re- duced and the cost of milk production will be favorably al- tered. In some cases the pasture is entirely eliminated, but this is not generally advisable, as the use of even a limited area of pasture has an ultimate beneficial effect on the health and production of the herd which cannot be obtained in any other way. The carrying capacity of, and the returns from, a pasture are greatly influenced by the method in which it is handled. It should be well drained and regularly manured. The prac- tice of feeding grain during the latter part of the pasturing season helps to keep up the fertility of the pastures. The stock should not be turned on to it in spring until the land is well dried and growth has obtained a good start. Stocking the pasture before there is a good cover lessens the vitality of the forage, and trampling on wet ground does much damage. Overstocking at any time is also inadvisable. Weeds detract from the value of a pasture and should be kept down. A great variety of pastures are in use, the commonest being blue grass. A good blue-grass pasture is excellent in spring and provides a considerable amount of good green forage in fall, but generally blue-grass pastures dry out badly during the summer and at that time are not very suitable for milk cows. In addition to blue grass, other grasses, such as Sudan PASTURE 123 124 MISCELLANEOUS SUCCULENT ROUGIL\GES grass, are used as pure pasture crops. Such usage is generally quite definitely limited to certain sections and is of little general importance, though frequently of great value in certain lo- calities. Legume crops, such as clover and alfalfa, are also used in the same way. There are disadvantages in the use of legimiinous pastures. Bloat frequently occurs on such pas- tures, considerable amounts of feed are generally wasted, and frequently the growing of the crop for hay is the more profit- able proposition. The necessity of improvement in the type of pastures used for dairy cattle is quite general, and one broad recommenda- tion will cover practically all conditions except in the drier sections. The best pasture for dairy cattle is one consisting of mixed grasses and legumes, as a mixture of grasses will pro- vide palatable forage over a longer season than will any one of its individual constituents. The addition of clovers in- creases the protein content of the feed, and the greater variety enhances the palatability of the forage. Good, well-tended pastures containing a variety of grasses and legumes are one of the greatest assets of the dairy farm, but it should be remembered that during hot, dry weather they must be supplemented with other succulent forage. ROOT CROPS Root crops are not much in evidence for the feeding of dairy cattle in any part of the United States, though they are widely used in the cattle-feeding and dairying sections of Great Britain and continental Europe and there is no doubt as to their value for feeding purposes. Roots, such as sugar beets, mangels, turnips and rutabagas, are highly nutritious and very palatable. They have a bene- ficial laxative effect on the digestion and general health of the animals and stimulate milk production. Roots are charac- terized by their high water content, 75 to 90 per cent, and the BEET PULP 125 small amount of fiber, fat and protein which they contain. A considerable amount of the nitrogen present is not in the form of protein and so is of doubtful feeding value. The nu- tritive ratio of roots is rather narrower than that of silage. The various roots, excepting sugar beets, are of very similar value for feeding purposes. Sugar beets, owing to their high sugar content, have a greater feeding value than do the other root crops. The dry matter of root crops is a httle more valuable than that of silage, as a rule. Some state that it is equal in value to that of grain, and that roots may even replace half the grain ordinarily fed in a ration composed of grain, mixed hay and silage. This is overstating the value of the roots. Roots are not used more extensively because of the labor involved and the difficulty of raising them and the conse- quent high cost of their production. Corn used as silage pro- duces considerabl}' more dry matter per acre than do root crops, and in addition the silage has the advantage of economy of production. Where roots can be produced cheaply, they may play a very important part in the dairy ration. They are especially valuable as appetizers, due to their succulent palatable na- ture, for feeding exhibition or show stock, and for cows that are being given a heavy ration with a view to stimulating maximum milk production. They are used to a considerable extent with cows being forced for records and may be fed alone or with silage. Where they are fed alone, 50 to 100 pounds per day may be allowed. BEET PULP Beet pulp is the residue obtained in the manufacture of beet sugar. The wet pulp, 2 tons of which are equivalent in feed- ing value to I ton of silage, is sometimes used for feeding pur- poses near the sugar factories, but owing to its high water 126 :\iis(:ellaxeous succulent kou(]iiac;es content and consequent danger of spoiling and diriicult}' of transportation it is seldom used far from the point of pro- duction. Beet pulp is usually obtained in the dried form and is a \ery excellent feed. It is classed by some as a concentrate, but better classed as a roughage, as it is usuall>- fed as part of the roughage ration. The dried beet pulp is sometimes mixed with the grain ra- tion and it is an excellent material for rendering the concen- trates bulky, though it has disadvantages for this purpose, as it has a great afhnity for water and may abstract moisture from the other contents of the digestive tract and then swell to an extent that may induce digestive troubles. It is usually soaked and fed as a succulence; this is the preferable method of feeding it. It should be soaked for ten to fourteen hours before feeding, and in this time it will take up about three times its weight of water. It can be used in this form, par- tially or entirely, to replace silage or roots. When fed as the sole succulence, from 4 to 8 pounds of the dried material per day can be given, and when fed with silage, 2 to 4 pounds will, as a rule, be sufficient. It has a cooling effect, aids in keeping the digestive tract in good condition, requires but Httle room for storage and is a very excellent succulence to use, especially where silage or roots are not available in quan- tities large enough for general herd feeding. It is a useful feed for stimulating production, and owing to its transporta- bility is specially valuable on the show circuit. POTATOES Potatoes are not much used for dairy-cattle feeding, but small unsalable ones can be utilized economically for this purpose. They can take the place of silage or roots, but not more than 20 pounds per head per day should be used. They are valuable mainly on account of the carbohydrates present. PUMPKINS 127 The dry matter in them is probably of slightly lower nutritive value than that in silage. There is a slight danger of cows choking when fed potatoes, and too large quantities will result in a salvy butter of poor flavor. PUMPKINS Pumpkins, when available, can be used satisfactorily for milk production, 2§ pounds of pumpkins being about equal to I pound of corn silage. It is sometimes said that pumpkin seeds tend to check milk production, but this statement is erroneous. CHAPTER XTV DRY ROUGHAGES The dairy cow is preeminently a consumer of rough feeds, and as large a proportion of her ration as possible should be made up of roughages. In this way the best returns can be obtained from feeds that would not otherwise have a high market value. The roughages used in the feeding of dairy cattle should, as a rule, be grown on the farm. There is no more economical way of marketing the home-grown hays and other roughages than by way of the dairy cow, provided that those grown are suitable for dairy cattle. The dry roughages supply a large amount of the bulk}' and fibrous part of the ration for dairy cows. This bulky material is necessary for the development of the digestive tract of young animals, and in the case of older animals it is essential for the most efficient digestion of the concentrated part of the ration. In addition, better returns can usually be obtained by feeding these roughages to the dairy cow than could be obtained by disposing of them in any other way. LEGUMINOUS Leguminous dry roughages are especially valuable for milk- producing cows, because of the fact that besides supplying bulk in the ration they also are capable of providing a con- siderable amount of digestible protein and other nutrients, and their ash content is usually of a valuable type, as it is high in calcium and phosphorus. Wherever possible, a 128 LEGUMINOUS 129 leguminous hay should be included in the ration of the dairy- cow. Alfalfa Hay. — This is undoubtedly the best dry roughage for dairy cows. It has a high content of valuable nutrients, especially protein and ash; it has a good effect upon the digestive system and is palatable. These properties, in addi- tion to its bulk, render it an excellent material for balancing the silage and corn part of the ration. For best results the alfalfa hay should be harvested in good condition. One of the main points to remember in curing alfalfa is that the leaf waste should be kept as low as possible. The leaves are the most nutritious portion of the plant, and every care should be taken to cure the hay with a miminum of handhng, as each time the hay is handled some of the leaves are lost. The relative values of the different cuttings of alfalfa de- pend, to a certain extent, upon climatic conditions. The crops with the fine stems and large proportion of leaves are to be preferred. At the Utah Agricultural Experiment Sta- tion it was found that no marked difference in value, for milk production, between first, second and third crop alfalfa ex- isted. It is true, however, that under western conditions a better quality of alfalfa hay can be harvested than is generally possible further east. In the middle-west and east, as a general rule, the first cutting of alfalfa tends to be coarser and less lea,fy than the later cuttings, and so is not of as high a value for the milk-producing cow. Alfalfa makes the most satisfactory hay for dairy cows, ex- celling in palatabihty, and being high in protein and ash, especially calcium, which is required in large amounts for milk production. Compared to bran, alfalfa hay furnishes about 80 per cent as much digestible protein, three times as much fiber and 65 per cent as much net energy. One of the important functions of alfalfa hay in the ration 130 DRY ROUGHAGES is to supply protein, but the limitations to its use should be recognized. Because of its low energy value, it cannot en- tirely replace concentrates, though where it is used, the grain ration may be reduced or may be less nitrogenous in character than would otherwise be required. Cows of low producing power may have their production stimulated to the highest degree by alfalfa hay, silage and very httle grain, but with good producers a liberal grain allowance is also needed. The allowance of alfalfa hay for milk cows should be about I to i§ pounds of hay per hundred pounds live weight daily. With heavy producing cows it is sometimes found ad\-isable to cut some of the hay into j-inch lengths, moisten, and mix with the grain before feeding. This allows of the fullest utilization of the grain allowance, and the concentrates may also be somewhat reduced under such circumstances. In the west, large numbers of cattle are reared without ever receiving any dry roughage but alfalfa hay. In spite of this, however, it must be stated that, in the majority of sections in this country, alfalfa hay is not the most satisfactory hay for young calves, as its high content of protein and ash tends to produce digestive and urinary disturbances. Alfalfa meal, like alfalfa hay, is a roughage and not a concentrate and cannot replace the grain ration. Some al- falfa meal is good, but in other cases poor quality hay is ground up and sometimes mixed with molasses and sold under trade names. If good alfalfa hay is obtainable, alfalfa meal should not be used ; ordinarily the dairy farmer can pro- duce roughage more economically than he can purchase it. Clover Hays. — The hays from the various clovers are worthy of great consideration for the feeding of dairy cows. As a whole they may be ranked as of about 80 per cent the value of alfalfa hay, from the standpoint of digestible protein content, though they are higher than alfalfa in net energy value. LEGUMINOUS 131 Red-clover hay is a valuable feed for milk-producing cows and under conditions of cheap protein concentrates its value compared to alfalfa hay is relatively increased. The feeding of red and other clover hays is very similar to that of alfalfa hay. Red-clover hay is more valuable for calves than is alfalfa. Mammoth red clover makes a rather poorer hay than does red clover, as it is coarser, larger-stemmed and not quite so palatable. Alsike clover is a fine-stemmed, palatable hay that ranks second to alfalfa hay in feeding value It is eaten with less waste than other clover hays and is the best hay for young calves. The hay from crimson clover is important in the south and is equal in feeding value to that from red clover. It should be cut by the time the flowers at the base of the most advanced heads have faded, otherwise the hairs on the heads and stems become hard and wiry and consecjuently are apt to form balls in the digestive tract and thus cause intestinal trouble. Sweet-clover Hay. — Not much experimental work has been done so far on the feeding value of sweet clover, though some rank it close to alfalfa hay. Stock usually object to sweet clover at the start when it is in the fresh green state. This is due to the presence of the bitter principle, cumarin. In the curing of the hay this objectionable substance is perhaps destroyed to some extent, and the hay is consequently more palatable than is the green feed. It supplies more net energy and crude protein but less digestible true protein than does alfalfa hay. One of the main objections to the use of sweet clover hay for dairy cattle is that it tends to become coarse and many of the leaves are lost in curing. Field-pea Hay. — Field-pea hay is approximately equal to alfalfa hay for feeding purposes. It is rather difhcult to cure, and consequently field peas are grown mainly in mixture. Cowpea Hay. — This hay is difficult to cure but is used to 132 DRV ROUGH,\GES a considerable extent in the south. It is thought to be about equal to alfalfa hay for feeding purposes. Soybean Hay. — It is about equal in feeding value to alfalfa hay but it is difficult to cure. In the past it has been used mainly in the south, but the cultix'ation of the soybean for forage purposes is extending quite rapidly. Leguminous Straws. — Where leguminous crops are threshed, as alfalfa or clover for seed, or soybeans for the grain to be used for stock-feeding or the manufacture of oil, there is left a straw which has some feeding value. The leguminous straws are much lower in feeding value than the corresponding hays, though much better than the cereal straws. Soybean straw for example, contains only 2.8 per cent of digestible crude protein and 43.5 per cent of total digestible nutrients, while the corresponding values for the hay are 11.7 per cent of digestible crude protein and 53.6 per cent of total digestible nutrients. The greatest loss is in the protein, as this is con- centrated to a considerable degree in the seeds which are removed. NON-LEGUMINOUS The non-leguminous roughages available for the feeding of dairy cattle have, as a rule, little to recommend them. They are unpalatable and poor in protein and other digestible nu- trients; and though they generally have a high ash content it is poor in calcium and phosphorus. In addition, the non-leguminous roughages are usually harvested and cared for in a very haphazard way and con- sequently deteriorate rapidly. In spite of this, however, a very large amount of these feeds is used for the feeding of milk cows in many sections. Though they have little value when used as the sole roughage, yet some of them can at times be used to advantage when limited amounts are fed with more valuable roughages. NON-LEGUMINOUS 133 Corn Fodder. — Corn fodder, though not as valuable as corn silage, makes a fairly good carbonaceous roughage. Where it has to be fed, some nitrogenous hay should also be used. Where there is silage and also some fodder, it is often advisable to give the cows a little fodde:: in addition to their silage They will relish small quantities of it, and a good plan is to give the cows access to it when out for exercise in the lots. Com Stover. — Owing to the absence of the ears, corn stover is of considerably less value than the fodder, but it can be used in a manner similar to that recommended for the corn fodder. Cereal Straws. — The cereal straws, being poor in protein, low in digestibility and unpalatable, are not suitable roughages for milk cows. Their feeding value is very low and they rank as follows: oat, barley, wheat, rye, in decreasing value. Timothy Hay. — This roughage is too fibrous and poor in protein to make a good cow-feed. Its feeding value is about the same as that of oat straw, and it should not be fed to milking cows. Frequently it can be sold for as high a price as it takes to buy alfalfa. The feeding of timothy to dairy cows is far too common at present, and everything possible should be done to discourage this practice. Sudan-grass Hay. — This recently introduced crop, which is especially adapted to the drier regions, is increasing in popu- larity in some sections. As far as protein supply is con- cerned, it is about equal to timothy hay, but it provides en- ergy about one-third more efficiently than does timothy and is more palatable. It is not a satisfactory hay for milk cows, but should prove fairly valuable for dry cows or young stock. The Sorghums. — Both the sweet, or saccharine sorghums, or sorghos, and the non-saccharine sorghums are valuable forage crops in the drier regions, especially in the southwest. If they are drilled in and intended for forage, they are cut before they are fully matured and shocked in the same man- 134 DRY ROUGHAGES ner as corn. They then produce a valuable fodder. If grown for seed, they are allowed to mature before shocking, and the stover obtained after threshing is not valueless. Kafir fodder and stover are the most valuable dry roughages of the grain sorghum group and have about the same value as the corre- sponding corn products, while the forages produced from feterita are of somewhat lower value, and milo, kaoliang and shallu come at the bottom of the scale. Sometimes these crops are sown broadcast; this gives a thick crop of fine- stemmed forage which when cut with a mower gives a valuable hay. Of the sweet sorghums, amber cane is the best known, as it can be grown over a wide range of territory, including all of the corn belt. It can be handled in the same way as corn fodder and, like all the other sorghum forages, it is not very high in protein and is best suited for the feeding of dry stock. The Millets. — Of the large variety of millets, none is really valuable as dry roughage for dairy cattle as they are all low in protein. The foxtail millets, including the common, Hun- garian and German types, are perhaps the best, and they are of some value in the drier regions of the northwest. They should be cut early for hay, before the hard seeds are formed. The Japanese Barnyard millet gives large yields of coarser feed, while the broom-corn millets give a low yield of very woody forage which is practically valueless for dairy cattle. Buckwheat Straw. — The straw of buckwheat contains more digestible crude protein but less digestible carbohydrate equivalent than the cereal straws. It is of very low value and may cause digestive disturbances if fed in liberal amounts and therefore should not be offered to dairy cattle. Flax Straw. — This is of low value, and the straw from green immature plants may contain enough prussic acid to be dangerous when fed to live stock. It should not be used with dairy cattle. MIXED 135 MIXED Only a few mixed dry roughages belong to this group, but they are quite valuable, especially where alfalfa or clover hays are not available. Mixed Hay. — Hay from niLxed grasses is better than timothy hay, and if there are also some legumes present it makes a fairly satisfactory feed. Mixed hay, even with legumes present, is not as good as alfalfa or clover hay for milk production, and when it is used, rather more nitrogenous concentrates will have to be fed than would be necessary if a legume hay were provided. Mixed hay is good for young calves, especially if there are plenty of legumes present. Oat and Pea Hay. — A mixture of oats and Canadian field peas, in equal parts and drilled in at the rate of 3 bushels per acre, will yield a good hay for dairy cows. The best results are obtained when the crop is cut just as the oats are entering the dough stage. Though not quite as good as alfalfa or clover hay it makes an excellent substitute, and is especially valuable where a crop of hay has to be obtained in the season in which the seeding is done. CHAPTER XV THE CEREAL GRAINS AND THEIR BY-PRODUCTS The concentrates include a very large number of materials of varied characteristics. They can be grouped according to their general character, frequently according to their content of crude protein. It is perhaps better, however, to consider them on the basis of their plant source, cereals, legumes and oilseeds. The cereal grains form one of the most important groups of feeding stuffs in the United States, and their scope is world- wide. They are generally considered as feeds used largely to provide energy, but many of their by-products are also valuable sources of protein. Most emphasis is generally put on corn, but in certain sections of the country other cereal grains are of more importance than corn. CORN AND ITS BY-PRODUCTS The corn crop of the United States exceeds, in acreage, yield of grain, and value, all the other cereals combined; it must therefore be rehed on as the main grain for the feeding of animals in this country, especially throughout the corn belt. Of the six races of maize grown, only three are of importance from the viewpoint of the feeder of dairy cattle. These are dent, flint and sweet corn. The dent and flint corns differ chiefly in the condition of the starch which they contain. Sweet corn contains more crude protein and fat and less car- bohydrate than the other races. Before ripening, sweet corn 136 CORN AND ITS BY-PRODUCTS 137 contains a large quantity of sugar, which is later changed to starch; and though this sugar is not more nutritious than starch it does increase the palatability of the corn. Sometimes the question of a difference in feeding value between yellow and white corn arises. In general the chemical composition of white corn is practically the same as that of yellow corn, though there may possibly be a difference in the constituents of the proteins of yellow and white corns. Recent investigations also indicate that yellow corn perhaps contains sufficient of the vitamine, Fat-Soluble A, for normal growth and reproduction, while white corn contains none of it. If this proves to be correct, it will be of great significance where corn constitutes the major portion of the ration of animals and will again emphasize the necessity for variety in the ration. Where the ration is varied in character there are no practical differences in the feeding values of yellow and white corn, though popular opinion frequently attributes a slightly higher value to the yellow variety. It has already been shown that the yellow color of butter fat is due to pigments, the carotinoids, derived from the feed, but yellow corn does not appear to give any more color to dairy products than does white corn. This is probably because the color of yellow corn is due to the presence of xanthophylls rather than of carotin. The corn grain has a low protein content, and of the pro- tein present about 58 per cent is zein and 30 per cent glutelin. Zein is an inefficient protein as it lacks tr^'ptophane and lysine, but it has been found that the mixed proteins of corn are more efficient than those of oats or wheat. Corn is also deficient in mineral constituents, especially hme, and sometimes phosphates. These are limitations which must be borne in mind in the feeding of corn, and a variety of constituents from other plant sources should be fed with the corn to overcome these deficiencies. 138 THE CEREAL GRAINS AND THEIR BY-PRODUCTS The handling of soft corn is a problem that occasionally con- fronts the dairy farmer. The best solution is to put it in the silo, but where it is not possible to ensile the crop the grain should be fed as soon as possible. Drying outfits are now to be had, and good results have been obtained with some of them. Fairly satisfactory results can also be obtained in the preservation of soft corn through the use of salt. It is recom- mended that one-half to one pound of salt per hundred pounds of soft corn be used at cribbing time. Soft corn has not as high a feeding value as an equal weight of well-matured corn, but when calculated on the dry-matter basis there is little difference between them, and there is no reason why soft corn cannot be utilized economically by the dairy cow if it is fed carefully and with the proper supplements. The main difiticulty in its use is the problem of storage, as the high moisture content is favorable to mold growth. Where corn is stored in large quantities, the shrinkage must be taken into consideration as it may amount to a considerable item. With good corn the shrinkage from November to April amounts to about 12 per cent, while during the months of November and December it is generally over 5 per cent. Good corn is generally figured on the basis of 14 per cent of moisture. Shelled corn does not keep as well in bulk as does ear corn, on account of the difficulty of maintaining proper ventilation for the removal of moisture. Com Preparations. — In the corn belt, corn is generally the most economical concentrate for providing energ}- that is available for the feeding of dairy cattle. On account of the limitations which have already been pointed out, corn should not, as a rule, be used as the sole concentrate for milk cows or other stock. This is especially important where the corn plant also provides part of the roughage used in the ration. There are several forms in which corn grain may be fed to dairy cattle, and these vary considerably in their efficiency. CORN AND ITS BY-PRODUCTS 139 Ear Corn. — The feeding of ear corn to dairy cows is much too common at the present time. About 20 per cent of ear corn is cob, which contains about 30 per cent of fiber and pentosans — carbohydrates of doubtful feeding value. No extensive work has as yet been done in comparing ear corn with other corn preparations as a feed for dairy cows, but experiments at the Iowa Agricultural Experiment Station indicate that ear corn is about 5 per cent less valuable for milk production than is cracked corn, when equal amounts of corn-grain dry-matter are fed; in other words, 100 pounds of ear corn, when fed to dairy cows, would induce the produc- tion of about 5 per cent less milk than would 80 pounds of cracked corn, or 105 pounds of ear corn are only equal to 80 pounds of cracked corn for milk-producing purposes. Shelled Corn. — This corn preparation is quite widely used and is slightly better than ear corn, but not as efficient as cracked corn for milk-producing purposes. Cracked Corn. — One of the best preparations of the corn grain for the feeding of dairy cattle is cracked corn, as the cracking renders it more palatable and probably allows rather more complete digestion. Where the grain ration contains plenty of bulky constituents, cracked corn should be used in preference to any of the other preparations, and under those conditions it is generally an economical source of energy either for the fattening of cows preparatory to freshening or for milk production. Corn Meal. — There is no definite line of demarcation between corn meal and cracked corn. From work done at the Iowa Station, it appears that there is no advantage to be gained by extreme fineness of grinding. Fine corn meal and cracked corn have similar values for milk production, but the more finely ground material has disadvantages. It is a heavy feed which is more difficult to digest than the cracked corn, unless a greater proportion of bulky constituents be 140 THE CEREAL GRAINS AND THEIR BY-PRODUCTS included in the grain ration. There is. therefore, no advantage to be obtained from the expenditure of the extra power required to bring the feed into the tine state of division in which it exists in corn meal. Corn-and-coh Meal. — In spite of the highly indigestible cob, corn-and-cob meal is an exceptionally valuable feed. WTiere there are no other bulky constituents in the grain ration, corn- and-cob meal is as valuable as cracked corn for milk-producing purposes; but where light, bulky constituents, such as ground oats and bran, are included in the grain ration, corn-and-cob meal is 20 per cent less valuable than cracked corn. This is due to the fact that the ground particles of indigestible cob are of no nutritive value and do not increase the efficienc\- of the ration when other bulky constituents are present, but when other light feeds are absent the particles of cob help to loosen up the grain niLxture and so render the corn-and-cob meal of higher value — not through adding nutrients to the ration, but simply by their mechanical effect. Com By-products. — Though corn is one of the most useful of grains, it is valuable also for other reasons. In the manu- facture of starch, glucose and alcohol from corn, several by-products are obtained which are at times valuable adjuncts to the dairy ration, especially as some of them contain a high percentage of protein. Quite frequently some of these protein feeds are easily available in the corn regions, but it should be remembered that it is not, as a rule, advisable to use them as the sole protein supplement where corn grain and corn silage form a large part of the ration, as their use does not make up for the deticiencies of the corn plant in the way of ash and certain constituents of the proteins. Hominy Feed. — In the manufacture of hominy grits, which are used for human consumption, or of brewers' grits, the by-product known as hominy feed is obtained. It is also known as hominy meal or chop, and is a mixture of the bran CORN AND ITS BY-PRODUCTS 141 coating, the germ and a part of the starchy portion of the corn kernel. It contains much more fat, sHghtly more fiber and less nitrogen-free extract than does corn. Like corn, it has a low content of protein. As it is light and bulky it is in some ways preferable to corn meal but it is less palatable. Hominy feed is less digestible than corn meal, but it keeps well and is remarkably free from adulteration. It is about equal to corn in feeding value and frequently forms an econom- ical source of carbohydrates. Germ-oil Meal. — In the manufacture of starch from corn, the germs are removed and dried and most of the oil expressed. The resulting material is sold as corn oil-cake or ground and sold as corn oil-cake meal, germ-oil meal or corn-germ meal. This feed contains less protein and more fat than does gluten feed and has a fairly good ash content. Its feeding value is fairly well indicated by its composition. However, it is not a very satisfactory concentrate for dairy cattle, as it is unpal- atable, and owing to its high fat content it tends to become rancid and so cannot be stored for any great length of time. Corn Bran. — The corn bran is the outer layer removed from the kernel in the manufacture of starch or glucose. It con- tains less crude protein and ash and more liber and total digestible nutrients than does wheat bran, and its protein is not very easily digested. It is usually an expensive feed, but Httle of it is now found on the market as it is generally mixed with other corn by-products. Where used as a protein sup- plement for milk cows, it is about equal in value to wheat bran. Gluten Meal. — When the bran, the germ and the greater part of the starch have been removed from the corn grain in the manufacture of starch and glucose, there is left the gluten and a solution of ash and other materials known as corn solubles. All of the gluten was at one time dried and sold as gluten meal or corn-gluten meal, but now the corn solubles are generally added, as this improves the ash content 142 11 no CKRKAL GRAINS AND THEIR BY-PRODUCTS of the gluten. Gluten meal is a heavy feed, having a tendency to cause digestive troubles, and so should be used only in limited quantities and with suitable admixtures of bulky feeds. Gluten Feed. — Gluten feed or corn-gluten feed is a mixture of gluten meal and corn bran and usually, though not always, contains the corn solubles. It is a feed high in protein, but it is much safer to feed than is gluten meal as the corn bran renders it comparatively light and bulky. Gluten feed is the best-known and most widely used of the corn by-products but, though it frequently is an economical source of protein it should not be used as the sole supplement to corn. Corn-distillers^ Grains. — This is the residue obtained in the manufacture of alcohol and distilled liquors from corn. This residue contains the crude protein, fiber, fat and more insoluble portions of the grain. A small part of this material is used as distillers' wet grains, but owing to the large amount of moisture it contains, with the consequent expense of trans- portation and tendency to fermentation, it is used in this form only near the point of production. It is a useful feed if properly handled, but if care is not taken it will ferment and may then cause digestive troubles. This fermenting material when left in the barns will also impart disagreeable odors to the milk. When dried, the residue is sold as distillers' dried grains and is a valuable concentrate. It contains about twice as much crude protein and three times as much fat as wheat bran and has a feeding value superior to that of gluten feed. It is palatable and its bulky nature renders it specially valuable. OATS AND THEIR BY-PRODUCTS The oat crop is grown over a wider area in the United States than any other grain. Though used to a considerable extent for human consumption its importance as a source of feed for WHEAT AND ITS BY-PRODUCTS 143 dairy cattle is obvious, though its by-products are of little importance. Oats. — The oat grain is used to a considerable extent in the human dietary, but very large amounts of it are available for the feeding of dairy cattle. Oats are higher in crude protein, fiber and ash than corn, and almost equal to it in fat content. There are no better grains than oats for milk-producing cows, and practically the only limit which needs to be put on their use is that due to economy. Though their use for general herd feeding is often limited by their price, it will usually be found advisable to include oats in the ration of high producing cows, and those that are well along in pregnancy or in poor condition. Oats are very palatable, especially when ground, and the grinding increases their bulk to a marked degree. The use of oats in the feeding of calves is also to be recom- mended, but with young calves the whole grain is preferred. Oat By-products. — There are several by-products, including oat hulls, and oat shorts or middlings, made in the manufacture of oatmeal, but they are of httle moment in the feeding of dairy cattle, except that they are frequently used as con- stituents of mixed feeds. Almost one-third of oat hulls con- sists of crude fiber, and they have little feeding value. They are usually incorporated with other feeds and their bulk may then have some beneficial effect. Oat middlings contain more fat than does wheat bran and, like oat bran, oat dust and oat clippings, they are usually put into compound feeds. WHEAT AND ITS BY-PRODUCTS Wheat is the chief American cereal used for human con- sumption, and its consequent high price precludes the use of much of it for cattle feeding, though its by-products are of considerable importance. There are several varieties, such as durum and macaroni wheats and emmer, which do not need separate consideration. 144 THE CERE.\L GRAINS AND THEIR BY-PRODUCTS Wheat. — Only the poor or spoiled samples of wheat are available for stock feeding, but this damaged grain differs little in composition from the marketable product, though it usual!)- contains a slightly larger amount of moisture and protein. Though wheat contains a little more protein than does corn, it is essentially a carbohydrate feed and is slightly lower than corn in feeding value. Wheat should always be ground before feeding and should never be fed alone; the presence of the proteins, gliadin and glutenin, and the absence of any marked amount of oil or fat, cause the formation, in the alimentary tract, of pasty masses of the same consistency as dough, and these may cause digestive disturbances. Wheat Bran. — The coarse outer coatings of the wheat grain, removed in the milling process, are the bran. The protein content of this feed is high and it has a fair amount of other digestible nutrients, though it has a relatively high content of crude fiber. The ash content is also high and is rich in phosphates, though poor in lime. Bran is a light, bulky feed, is extremely palatable and has a beneficial laxative and cooling effect on the digestive system. Its laxative action is due to the presence of phytin, an organic compound containing phosphorus, magnesium and potassium. Wheat bran has a feeding value about equal to that of oats. Owing to its high price, bran is sometimes not a very economical supplement for corn and other carbonaceous feeds. It can seldom be profitably fed to all the animals in a herd, but even when it is high-priced it is usually advisable to feed it to cows just before and after freshening, to animals that are being forced for records, and to young stock. Its laxative properties and its palatability render it extremely useful, in the form of mashes, for cows that are off feed or otherwise out of condition. Wheat Middlings. — Shorts, standc^rd middhngs, or wheat middhngs, are the fine particles of the outer and inner bran separated from the bran and white middlings. Though they BARLEY AND ITS BY-PRODUCTS 145 have a higher protein content than wheat bran they should seldom be fed to dairy cows, as they are unpalatable, and more economical sources of protein can usually be obtained. When fed they should be used only in small quantities and mixed with other feeds. Flour-wheat Middlings. — Flour or white middlings are that part of the wheat offal intermediate between shorts and red dog flour. This feed contains less crude fiber and more pro- tein than do the standard wheat middlings. Like shorts, they should be fed but rarely and then only in limited quantities. Red Dog Flour. — This is a low-grade flour containing the fine particles of bran. It contains less fiber and ash and more nitrogen-free extract than does wheat bran, and in feeding value it is very similar to good white middlings. BARLEY AND ITS BY-PRODUCTS In the past the use of barley for feeding purposes has been restricted largely to the Pacitic-coast region in this country, but its use in the feeding of dairy cattle has recently shown a fair degree of expansion. Some of the by-products, however, have been more widely used. Barley. — Though containing more protein than does corn, barley is strictly a carbohydrate feed. Many feeders are prejudiced against the use of barley for milk-producing cows on the ground that it tends to cause the cows to dry up. This prejudice is unfounded; cows have been fed with barley as the sole grain throughout the lactation period without any deleterious effects. In the past, only damaged barley has been available for feeding purposes in certain sections, but this discolored grain is quite as fit for feeding purposes as the brighter samples. Where it can be purchased economically, barley will be found to be a good energy-providing feed. It is a palatable feed and has a nutritive value just about the same as that of wheat and about midway between that of 146 THE CERE.\L GRAINS AND THEIR BY-PRODUCTS corn and oats. It is generally fed ground, cracked or rolled, but the rolled grain is to be preferred as the ground barley forms pasty, indigestible masses in the alimentary canal. Barley Bran and Barley Shorts. — These feeds contain less protein than do the corresponding wheat products and are of very Httle importance in dairy-cattle feeding. Malt-sprouts. — The sprouts separated from malted barley are dried and sold as malt-sprouts. Their content of carbo- hydrates and fats is low, and they contain a large amount of digestible crude protein, though about one-third of it is amides and of httle feeding value. They are a light, bulky feed, but owing to the presence of betaine and choline they are unpalatable, though stock may acquire a liking for them. They are of lower feeding value than brewers' dried grains. The feeding of over 2 pounds per day cannot be advised and their use is open to criticism. Malt-sprouts have a great affinity for water, and as they swell greatly when moistened they should be soaked for several hours before feeding, as this will prevent digestive disturbances. Where only small quanti- ties are fed, soaking may not be necessary, but in this case the malt-sprouts should be mbced with other feeds as they are extremely dusty. Brewers' Grains. — This is the residue of the malted grain, obtained in the manufacture of beer and non-alcoholic beer substitutes. The brewers' wet grains, like distillers' wet grains, are in common use for feeding purposes only near the point of production. When properly handled they make a profitable feed, the usual daily allowance being 20 to 30 pounds per cow. It is very essential that they be fed before decom- position starts; otherwise digestive disturbances are sure to result, and the odors from the decomposing feed will also be imparted to the milk. They differ from the barley grain chiefly in the water-and-carbohydrate content and they are worth about one-fourth as much as the dried grains. Brewers' RYE AND ITS BY-PRODUCTS 147 dried grains are a palatable and bulky feed and at times have been an economical source of protein. They have a rather higher value for milk production than has wheat bran. RYE AND ITS BY-PRODUCTS Rye does not differ materially from barley in composition or feeding value. It is preferably fed ground and mixed with a relatively large proportion of other feeds, as it is unpalatable to dairy cows and may impart a disagreeable bitter flavor to milk and butter. If fed alone or in large quantities, it may also cause digestive disturbances, and its importance in the dairy ration is not great. The chief rye by-products are middlings, bran and dis- tillers' grains. The rye middhngs and bran do not differ much from the corresponding wheat by-products, except that they are somewhat lower in fiber, fat and protein and are unpalat- able. Rye distillers' grains contain considerably less protein and fat than do those made from corn, and consequently are of less value in the feeding of dairy cattle. RICE AND ITS BY-PRODUCTS Damaged and low-grade rice, both rough and hulled, is sometimes fed to cattle and has a slightly higher feeding value than corn. Like corn, it is used as a source of energy. The amount available for feeding purposes is small. Rice hulls, the first layer removed from the grain in the preparation of rice for human consumption, should never be fed to cattle, for not only are they unpalatable, very fibrous and practically devoid of digestible nutrients, but they contain a large per- centage of siliceous or sandy material which causes great irri- tation in the digestive tract and may even result in death. 148 THE CERE.VL GRAINS AND THEIR BY-PRODUCTS The rice bran, the layer just within the hull, is removed in preparing rice. It is a fairly nutritious feed if it has not been adulterated with the hulls, but owing to the large amount of oil present it is not a very satisfactory feed, as the breaking down of the oil causes it to develop rancidity rapidl}- in storage. Rancid rice bran is unpalatable and may taint the milk, but it is said that the rancidity can be prevented by kiln-dr}dng the bran. Rice polish, removed from the grain after the hulls and bran have been separated, is equal to corn in feeding value, but the demand for it in the arts removes most of it from the list of feeds available for dairy cattle. THE SORGHUMS The sorghums are drought-resisting plants, of importance in the arid and semi-arid regions only. They may be divided into the non-saccharine or grain sorghums, and the saccharine or sweet sorghums, or sorghos. The latter are used mainly for forage purposes, though in some cases the grains produced are used to a sHght extent as concentrates. The non-saccharine or grain sorghums include kalir, durra, milo, feterita, kaoHang and shallu. They are all very similar in composition and are essentially energy-providing feeds, carrying about the same amount of crude protein and nitrogen- free extract as corn. They are not quite so palatable as corn. The grain is usually ground, and in some cases the entire head is ground, the product then resembling corn-and-cob meal in composition. Kafir grain is astringent and constipating in action, and so must be fed with laxative feeds and only in moderate amounts to milk-producing cows. Milo is superior to kafir, as it is more palatable and has a laxative efifect on the digestive sys- THE MILLETS 149 tern. Feterita and kaoliang are of less value than milo and kafir, while the others mentioned are of no great importance THE MILLETS The grain of the various millets is used but little in the feeding of dairy cattle, and is 20 to 25 per cent less valuable than corn. When used, it should be ground. CHAPTER XVI THE LEGUMES, THE OIL SEEDS AND THEIR BY-PRODUCTS The concentrates included in this grouping come from a wide variety of sources and are of importance largely on account of the liberal amounts of protein which they supply. The legumes provide the most useful and valuable dry rough- ages for dairy cattle and, in addition, some exceedingly valu- able concentrates are obtained from them. The concentrates of leguminous origin have a high content of protein, and in some cases this has been accentuated by the extraction of the oil, which is generally present in liberal amounts. Of the non-leguminous oil seeds, only two, cottonseed and flaxseed, contribute large amounts of feed useful to the dairy farmer; the others, the coconut and palmnut, are not yet of great importance in America. PEAS The common field, or Canadian field, peas make a very good concentrate although they are not very widel}' used in the feeding of dairy cattle. They contain about twice as much digestible crude protein as the cereal grains and are also rich in phosphorus and potash. They are probably equal to gluten feed for milk production and should be fed cracked or ground In combination with corn they may form one-third to one- half of the grain ration. 150 COWPEAS 151 COWPEAS Owing to uneven ripening and the consequent difficulty in harvesting, cowpeas are used mainly as a forage crop. They are very similar to the field pea in composition and when fed should be cracked. BEANS Most of the beans grown in this country are used for human consumption, but there are many damaged and cull beans which can be used successfully for feeding dairy cattle, as they are rich in protein. They should be cracked before feeding or ground into a meal. The former method of preparation is the better, as the meal is a heavy feed. In the south, velvet beans have proved to be valuable for milk production, but they must be ground before feeding. SOYBEANS Of all the leguminous seeds used in cattle feeding, soybeans are the richest in crude protein and ash. They are a valuable crop in the south, although in the past they have largely been used as a forage crop. The soybean is adaptable to the same range of climate as corn, however, and the prospects for its expansion in the future are good. Soybeans should be cracked before feeding. They are very palatable and are quite comparable to the other feeds of high protein content as far as their value for milk and butter-fat production is concerned, though too large an allowance of soybeans in the ration will cause the production of a soft butter. Large areas of the United States, m which corn can be grown, successfully produce all the roughages needed for dairy cattle as well as plenty of energy-producing concen- trates. They are, however, now dependent on outside sources 152 LEGUMES, OIL SEEDS AND THE BY-PRODUCTS for concentrates of high protein content. But if the develop- ment of the soybean as a grain crop progresses as rapidly as it is doing at present, there appears to be a good opportunity for those sections to become absolutely independent as far as all dairy-cattle feeds are concerned. The soybean, ha\ing a high oil content, is used in the manufacture of oil, and the resulting by-product is used for feeding purposes. For a number of years this soybean cake or meal was imported from the Orient and used on the Pacific coast with good results. Now, however, the extraction of soybean oil is a rapidly growing industry in the United States, and greater amounts of the soybean meal are yearly becoming available for cattle feeding. It appears to be of about the same value as oil meal for milk production, and as the oil has been extracted there is less risk of it producing a soft butter than there is where the unextracted beans are fed. PEANUTS Unextracted peanuts, though used in the feeding of hogs in the south, are not used for dairy cattle. Peanut meal, which is the ground residue left after the oil has been extracted, is used to some extent, however. When this meal is made from hulled peanuts it contains over 40 per cent of digestible crude protein and it seems to be of about the same value as oil meal for milk production. The meal from the unhuUed nuts is called peanut feed and contains about 23 per cent of crude fiber and 20 per cent of digestible crude protein. Peanut products tend to produce a soft butter and are not very palatable to dairy cows, though they do become accustomed to them. Peanut hulls are sometimes ground and used for adulterat- ing feeding stuffs and are also fraudulently sold as " peanut bran." They contain over 50 per cent of crude fiber and are less valuable than straw for feeding purposes. COTTONSEED AND ITS BY-PRODUCTS 153 COTTONSEED AND ITS BY-PRODUCTS At one time the seed of the cotton plant, after its separation from the lint, was allowed to go to waste or, at the best, used for fertilizer. Now, however, the miUions of tons of cottonseed produced annually in the United States are used largely for feeding purposes. It has been shown, by both practical and experimental work, that cottonseed is not always a safe feed. The seed itself, and also its products, may under certain conditions cause peculiar physiological disturbances which result in a staggering gait, sometimes blindness and even death. These effects are most easily produced in the case of young animals and con- sequently cottonseed products should never be fed to calves and other young stock. The exact cause of this deleterious effect of cottonseed prod- ucts has not yet been determined, though it has been attributed to many factors. It is generaly conceded that these effects are poisonous rather than the result of a nutritional insufficiency of the cottonseed. This toxicity has been ascribed to many factors at one time and another, but most of these factors have now been removed from the list of possible deleterious agents. None of these need be mentioned, with the exception of prussic acid. It has been at times held by some that the presence of prussic acid was the cause of cottonseed poisoning. Cot- tonseed products, like many other feeds, may at times, when in bad condition, contain enough prussic acid to cause poison- ing, but as a general rule cottonseed shows no tendency to contain prussic acid, and the typical symptoms of cottonseed poisoning are not those of prussic-acid poisoning. There remain at present two substances which are classed as the causes of . typical cottonseed poisoning. These are gossypol, a pigment found in cottonseed, and a sulphur com- bination which occurs in the protein of cottonseed. Gossypol 154 LEGUMES, OIL SEEDS AND THE HV-PRODUCTS is present to the extent of about .6 per cent in the raw cotton- seed kernels, and, as it is soluble in oil, about three-fourths of it is removed when the oil is expressed by the cold-press method. The hot-press method of extraction reduces the amount of gossypol present in cottonseed products still further, as the heat has a destructive effect on it. The gossj-pol is supposed to have a general poisonous elTect. It is also stated that the sulphur of the protein of the cottonseed abstracts iron from the blood, thus reducing its oxygen- carrying properties and ultimately resulting in the character- istic s>Tnptoms of cottonseed poisoning. Which, if either, of these two substances is directly respon- sible for cottonseed poisoning, has never been definitely determined and no very successful antidote has been found, though it is stated that the administration of iron sulphate, or copperas, in the drinking water of stock will prevent, or at least delay, the onset of typical cottonseed poisoning. Those who attribute the toxicity to gossypol say that the iron of the copperas unites with the gossypol, thus rendering it harm- less; while those believing in the sulphur of the protein as the dangerous element assume that the trouble is prevented through this sulphur combining with the additional iron in the digestive system and consequently being unable to abstract the iron from the haemoglobin of the blood. No matter what the cause, it should be remembered that cottonseed products are not suitable feeds for calves but that they are satisfactory for dairy cows when fed with a suitable ration. Cottonseed. — Very little whole cottonseed is now fed to dairy cattle as nearly all of it is used in the manufacture of oil. In certain sections of Europe, however, the whole cottonseed is sometimes ground and fed. This gives a very concentrated product, high in both protein and fat, and owing to its high content of oil it is difficult to store and handle. It is not a very satisfactory feed as it tends to produce digestive troubles. COTTONSEED AND ITS BY-PRODUCTS 155 Cottonseed Hulls. — The hulls removed from the cottonseed before the oil is extracted are high in hber and exceptionally low in their content of digestible nutrients. In the south they are sometimes used to add bulk to the ration, but as a rule more valuable methods of rendering a ration bulky can be obtained. Cottonseed hulls are also sometimes used as a filler in cottonseed and other feeds, but they should not be bought for the feeding of dairy cattle. Cottonseed Meal. — This is one of the richest and most nitrogenous feeds available and is often an economical source of protein. It is composed principally of the kernel with such portion of the hull as is necessary in the manufacture of oil, and legally must contain at least 36 per cent of crude protein. Cottonseed meal is sold according to grade; the three grades recognized are as follows: choice, containing at least 41 per cent; prime, containing at least 38.6 per cent; and good, containing at least 36 per cent of crude protein. Besides being high in protein, cottonseed meal contains a relatively large amount of fat and ash, and these constituents also add to its value. It has a constipating action and therefore should be fed with some laxative feeds, such as linseed-oil meal and bran. Cottonseed meal should always be bought subject to guarantee, as it varies greatly in protein content. It should be in good fresh condition, as moldy meal, Hke other damaged feeds, is not only unpalatable, but may also be dangerous to stock. Under certain conditions any grade of cottonseed meal may prove poisonous; it should never be fed to young calves or to cows about to freshen, and the feeding of it to bulls is not good practice. However, there is no danger in feeding a limited amount, up to 2 pounds per day, to milking cows, provided it is mixed with laxative, bulky and less nitrogenous feeds. It is an excellent feed for cows when on pasture, as its constipating effect counteracts the action of washy grass, and, unlike oil meal, it tends to 156 LEGUMES. OIL SEEDS AND THE BY-PRODUCTS harden the butler, which is oftentimes soft (hiring summer, Where silage or roots are used it is an excellent feed in winter, but it should not be included in a ration containing no suc- culent feed. Sometimes cottonseed meal contains excessive amounts of hulls, due either to incomplete separation before the meats are ground for the oil-extraction process or to intentional adulteration with hulls. The excess of hulls detracts from the value of the meal. The presence of large amounts of hulls can be detected by a very simple process. A teaspoonful of the meal is stirred up with about two ounces of boiUng water until all the particles are wet and floating. The mix- ture is allowed to settle for five to ten seconds and the super- natant liquid is decanted. The liquid poured off is mustard colored, and the presence of a dark-brown sediment in large amounts indicates adulteration. This sediment is ground-up hulls and it can be washed once or twice to free it from the meal. This is only a comparative test, but an adulterated meal will give a much larger sediment than will a good sample. Cottonseed Feed. — This is a mixture of the meal and hulls of the cottonseed and contains less than 36 per cent of protein. It is of less value than cottonseed meal, the content of hulls and protein being the factors which indicate its relative feeding value. Cold-pressed Cottonseed Cake. — This is the product re- sulting when the oil is extracted from the undecorticated, or unhulled, cottonseed by the cold-pressure process and it includes the entire cottonseed less the oil extracted. This feed contains more fiber than does cottonseed meal, on account of a larger percentage of hulls, and it is consequently less valuable as a feed. It is usually sold as broken cake but sometimes it is ground into a meal. It is also put on the market under various trade names. FLAXSEED AND ITS BY-PRODUCTS 157 FLAXSEED AND ITS BY-PRODUCTS Flaxseed and its by-products provide some feeds which are among the most widely used, and which are very valuable on account of their high protein content and their laxative properties. The laxative action is due to the presence of com- pounds which absorb water very readily and, becoming mucilaginous, lubricate the intestinal tract. Cases have been reported where animals died from prussic- acid poisoning when fed oil meal and other flaxseed products. Flaxseed products contain cyanoglucosides and an enzyme which is capable, under certain conditions, of splitting off prussic acid from these glucosides. As a rule, however, this does not take place unless the feed has become moldy, has been heated, or in other ways caused to ferment. The bulk of this pernicious enz^-me is destroyed by the heating in the manufacture of oil meal by either the old or new process and consequently there is little danger of poisoning from this feed unless it is moldy or otherwise spoiled. In the feeding of unextracted flaxseed or flaxseed meal to young calves, it is probably best to make it into a mash with boiling water and keep it hot for an hour or two before feeding. This should drive off any prussic acid that might be formed and thus prevent any risk of poisoning. Flaxseed. — Flaxseed is too expensive to use in the feeding of mature cattle, but it is sometimes used, in the form of a meal, for the feeding of young calves. It has a high content of protein and oil and has a laxative action which is very valuable. It is too expensive to be widely used, however. It is used to a slight extent, in the ground form, with cows that are being forced for records. Linseed-oil Meal. — This is the ground product obtained after the extraction of the oil from the flaxseed. It is a widely used and valuable feed. There are two varieties of it, 158 LE(;UMES, OIL SEEDS AND THE liV-I'RODUCTS the old process and the new process. The old-process oil meal is the ground product obtained after extraction of part of the oil from the flaxseed by crushing, cooking and hydraulic pressure, while the new-process oil meal is the ground product obtained after extraction of part of the oil from the flaxseed by crushing, heating and the use of solvents. The oil extraction is more complete in the case of the new- process than in the case of the old-process meal, therefore the old-process meal contains rather more oil and less protein than does the new-process meal, and is rather more valuable. Owing to their similarity there is danger of substitution, but the following simple test makes it easy to distinguish between them. Put a little of the finely pulverized meal in a glass and to it add ten times its volume of boiling water. Stir thoroughly and allow to stand undisturbed for an hour. If the meal settles to the bottom and leaves the water clear, it is new-process; if the mixture remains jelly-like, it is old- process meal. Old-process linseed-oil meal is one of the best feeds for dairy cows. It contains a large amount of digestible nutrients and has a laxative and cooling effect upon the digestive system. It is a very safe feed, and though its relatively high price sometimes causes it to be a less profitable source of protein than some other feeds, it is often advisable to use it, in spite of its high price, for calves, bulls and animals that are off feed, in low condition or being prepared for freshening or Advanced Registry tests. One or 2 pounds per day makes an excellent addition to a ration. The old-process meal contains 3 per cent less crude protein and 4.5 per cent more fat than does the new-process meal, is more digestible and also has a better effect on the digestive system. It should be fed instead of the new-process if the difference in price is not too great. COCONUT MEAL 159 COCONUT MEAL Coconut, or copra, meal contains about i8 per cent of digestible crude protein, and its fat content varies consider- ably. It is a feed that has given good results in Europe and also on the Pacific coast, the main section of this country in which it has been tried. Many claim that it will cause a temporary increase in the fat content of milk. It is very palatable when fresh, but tends to become rancid if stored for long periods. Even though it has a lower protein content, it is perhaps almost as valuable as oil meal for dairy cows, PALMNUT MEAL This feed, like coconut meal, has not been used much in this country, but has been used successfully in Europe. It con- tains less protein and fat, as a rule, than does coconut meal. CHAPTER XVTT MISCELLANEOUS CONCENTRATES Most of the feeds used for dairy cattle are of vegetable origin; a few of these that cannot be conveniently discussed elsewhere are included here. There are also feeds derived from animal sources, some of which are very valuable and universally used, though some are of little importance. With these standard concentrates are also included the proprietary feeds, of which there are a multitude. BUCKWHEAT AND ITS BY-PRODUCTS Buckwheat is frequently classed with the cereals, but it does not belong there as it is a polygonaceous plant. Buckwheat itself is seldom used in the feeding of dairy cattle, and the buckwheat by-products are not of primary importance. Buckwheat middlings make quite a good feed as they are fairly palatable and contain over 28 per cent of crude protein. Usually, however, they are mixed with the hulls and sold as buckwheat feed, which is rather unpalatable and though slightly less valuable than bran is used to some extent. Fre- quently, too many hulls are added to the mixture, and this results in a feed of high fiber content and little value. MOLASSES Molasses is a valuable carbohydrate feed, but it is frequently too high in price to be used economically in general herd feeding. Beet and cane molasses differ little in composition. 1()0 DAIRY PRODUCTS 161 Each contains about 65 per cent of nitrogen-free extract, nearly all of which is digestible, and only a small amount of crude protein which, consisting largely of amides, is of doubtful nutritive value; neither contains fat or fiber. Though both types of molasses are laxative in character, the beet molasses is sometimes more purgative in action on account of the pres- ence of alkaline salts, organic acids and other substances. Molasses cannot be conveniently fed alone, and it is usually mixed with, or poured over, other feeds and is frequently diluted with water before being used. Though it cannot always be used economically it is frequently to be advised where inferior or unpalatable feeds have to be utilized, as under such circumstances it will cause the animals to make good use of feeds which might otherwise be wasted. An addition to the ration of 2 to 3 pounds of molasses per head per day is fre- quently of advantage in such cases. It can also be used satis- factorily where cows are being forced for production, and maximum feed consumption is desired. DAIRY PRODUCTS Milk and the by-products obtained in the manufacture of Dutter and cheese are used for the growing of calves but not generally for older animals. The efficient use of these feeds means a large addition to the income of the farmer. Owing to the fact that they arc generally easily obtainable, their true value is frequently overlooked. Whole Milk. — This is undoubtedly the best leed for young calves, as it supplies them with the nutrients they need in the right proportions, but it can seldom be used economically in the raising of calves as the market price for whole milk or butter fat is usually sufiiciently high to bring in greater returns than can be obtained by the feeding of the whole milk to calves. In spite of this, it should be supplied to the calves during their first few weeks of life. 162 MISCELLANEOUS CONCEN rRATES Skim Milk. — Calves can be successfully reared on skim milk, provided the feeding is done intelligently. Skim-milk calves are not always in as good condition as are calves fed on whole milk, but the gains in live weight can be obtained more economically and the animals will develop into as good cows as those fed by the more expensive method. The taking of the butter fat from the milk does not render it valueless for calf-feeding, but substitutes should be provided for the mate- rials removed, and this is generally most efficiently done by the supplying of grain. Buttermilk. — Buttermilk, when obtained fresh and un- diluted, is just slightly lower in value for calf-feeding than is skim milk. Care should be taken to prevent it from deteriorating before it is fed. Whey. — Fresh undiluted whey can be successfully employed in the feeding of calves, though its value is not more than half that of skim milk. It should be remembered that whey, unlike skim milk and buttermilk, is not a high protein feed, as it contains less than i per cent of digestible crude protein and more than 5 per cent of digestible carbohydrate equivalent, while skim milk contains 3.5 per cent of digestible crude pro- tein and 5.5 per cent of digestible carbohydrate equivalent. Consequently, the supplementary grain fed with it should be of relatively high protein content. Dried Dairy Products. — Various brands of dried milk, skim milk and buttermilk are to be obtained on the market. These are in powdered or semi-solid form and can be successfully used in the feeding of calves when the prices asked for them are not too high. As a general rule they are not advisable where skim milk is available, though they are frequently of value in the market milk regions where all of the product from the cows is marketed. PACKING-HOUSE BY-PRODUCTS 163 PACKING-HOUSE BY-PRODUCTS The packing-house by-products are concentrates of very high protein content and of considerable importance in the feeding of live stock. Up to the present time, however, they have not been used to any considerable extent with dairy cattle and they will probably never become popular for this purpose. Tankage. — Tankage is seldom used as a dairy cow feed in this country, but in Europe good results have been obtained when it was fed to milk cows at the rate of 2 to 3 pounds per thousand pounds live weight. It will probably never be popular as a dairy-cattle feed in this country, owing to the high price it commands for hog-feeding purposes, and the large supply of more popular protein feeds. Its palatability to dairy cows is also much in doubt. Blood Meal. — It has been found that, pound for pound, blood meal is twice as valuable as cottonseed meal for milk- producing purposes. It is not commonly fed to dairy cows and will probably never be popular. When it is used, it should never be given in amounts greater than i to 2 pounds per head per day. At the present time many are advocating its use for calf-feeding, and it seems to be giving good results when used as a constituent of milk substitutes, as it has a tendency to prevent scours. FISHERY BY-PRODUCTS The fishery by-products are not of much importance as dairy-cattle feeds, but there is a possibility that they may be of greater importance in certain sections in the future. They are used to a considerable extent in Europe at the present time. They are rather unpalatable to dairy cows and if not fed carefully may impart a disagreeable odor to the milk. Fish Meal. — This generally contains less protein and fat than does good tankage. It is fed to cows to some extent in 164 MISCELLANEOUS CONCENTRATES Europe and it is reported that when it is fed at the rate of about 2 pounds per head daily it produces no bad efYects on the milk and is of about the same value as cottonseed meal, though the Federal Department of Agriculture reports that it is about 20 per cent more valuable than cottonseed meal. Whale Meal. — This is used for dairy cattle-feeding in Europe to some extent, but is of no great importance in this country, its value and future prospects being perhaps about the same as those of fish meal. PROPRIETARY FEEDS In some cases the man in charge of live stock believes that he does not possess the knowledge necessary to choose his concentrated feeds to the best advantage, while in other cases the farmer prefers to buy ready-mixed feeds and thus be saved the trouble of compounding the grain ration for his cows. As a consequence there are now a large number of proprietary mixed feeds on the market. Proprietary feeds cannot be favored or condemned as a class, but need individual consideration. Standard Feeds. — These usually consist of well-known con- centrates sold under trade names. Generally only one con- stituent is present, some of the feeds that have been sold in this way to a considerable extent are brewers' dried grains, distillers' dried grains, gluten feed and cold-pressed cottonseed cake. They are usually valuable feeds and when sold at reasonable prices can be recommended for the feeding of dairy cattle. Mixed Concentrates. — A large number of manufacturers put on the market feeds that are mixtures of good concen- trates; practically any of the common feeds can be found in such combinations. They are usually good feeds and can be bought with safety when the price paid for them is in pro- portion to the amount of digestible nutrients they contain. PROPRIETARY FEEDS 165 Occasionally valuable concentrates are used to mask the pres- ence of worthless waste materials which could not otherwise be disposed of. Alfalfa-molasses Feeds. — There are on the market many feeds the basis of which is ground alfalfa hay or alfalfa meal. They usually contain some molasses. Practically any of the common concentrated feeds, as well as a large number of use- less materials and adulterants, can be found in combination with the basal materials. Many of these feeds, put out by reliable firms, are made from good alfalfa hay and concentrates of high quality. Such feeds are legitimate, and their sale cannot be criticized as long as they are priced in accordance with the amount of digestible nutrients they contain — a reasonable allowance being neces- sarily made for the preparation of the feed. On the other hand, quite a number of alfalfa-molasses preparations are made from very poor quality alfalfa hay, or even alfalfa straw, flavored with molasses and containing rather negligible amounts of concentrates. Damaged grains, mill refuse and other materials of doubtful feeding value are also used in their elaboration. Feeds of this nature have no place on the dairy farm. Peat-molasses Feeds. — The handling of molasses is dif- ficult, and some feeders prefer to have their work simphfied through the absorption of the feed by peat. Peat-molasses feeds are perhaps convenient to handle, and the trade in such materials is no doubt legitimate when they are sold for what they are — molasses absorbed by peat. However, some firms make extravagant statements regarding such mixtures and even attribute a direct feeding value to the peat. Such statements are unwarranted. The peat used in the preparation of mixed feeds may con- tain as high as 25 per cent of moisture, and the buying of water in mixed feeds is always expensive. The claim is 166 MISCELLANEOUS CONCENTRATES frequentxy made that the peat will neutralize any free acids present in the molasses; but peat is in itself acid in reaction and so cannot neutralize any acid that might be present in the molasses. Moreover, neither cane nor beet molasses is acid in reaction, as a general rule. Where the ash content of peat has not been aflfected by wind- or water-borne materials, during its formation, it will be low and of little consequence as far as the animal economy is concerned. On the other hand, many peats have a high ash content due to the deposition of sand at the time of their formation. Some peats are known to contain over lo per cent of sand; if these were fed to animals they would be harmful rather than beneficial, as the large amount of sand would produce intestinal irritation leading to scours, and might even result in the death of the animals. The fats or oils in peat are practically negligible in quantity and are very probably not available to animals. At times the dry matter of peat may contain about i per cent of fatty ma- terial, a small portion of which might be digestible. The materials from which peat is derived contain proteins; but these are to a great extent broken down during the process of peat formation and give rise to simpler non-protein nitrogenous compounds. It has been shown that, as a rule, the dry matter of peat contains less than 2.6 per cent of nitro- gen and that 6.6 per cent of this nitrogen might be digested by animals. If this nitrogen that might be digested were protein nitrogen, the highest amount of digestible crude protein that could occur in peat would be .8 per cent, but as this nitrogen is undoubtedly mainly, if not entirely, non- protein nitrogen, it is evident that peat cannot be looked on as a protein concentrate. Of the carbohydrates in peat, practically none of the nitrogen-free extract is available. A small amount of the pentosans may be available, but they are of doubtful value. PROPRIETARY FEEDS 167 The fiber has still to be accounted for. The dry matter of peat may contain as high as 25 per cent of crude fiber and some of this is at times digestible. The digestion of this fiber, however, is a net loss, rather than a gain, to the animal as more energy is required to digest and assimilate fiber than the fiber itself provides. The excessive amount of fiber present, in comparison with the other constituents, nulhfies any nutritive effect these might have, as the digestion of the fiber uses up more energy than could be provided by the small amount of other nutrients that might be present. The fact that some digestible nutri- ents may be present is no real indication that peat has a positive nutritive value, because the eftorts expended by the animal in obtaining these nutrients cause the use of more energy than the nutrients furnish. It has also been shown that peat not only possesses no nutritive value in itself, but also depresses the digestibihty of the substances with which it is fed. This is due to its high fiber content. Consequently, it may be said that, though peat is a convenient agent for the absorption of molasses, it possesses no inherent nutritive value of its own and may even depress the digestibility of the other constituents of the ration. Fillers. — Many mked feeds of little or no value are on the market. They are usually composed of waste materials which cannot be disposed of in any other way, sometimes with the addition of constituents which will increase their apparent content of protein and substances which will impart to them a pleasing aroma and an appetizing flavor. Some of the substances frequently used in the manufacture of such preparations are mill sweepings, ground corncobs, cot- tonseed hulls, oat hulls, flax-straw refuse and ground peat. The majority of these materials are absolutey devoid of feeding value, and in some cases they may contain so much 168 MISCELLANEOUS CONCENTRATES grit and sandy material as to be dangerous when fed to live stock. Feeds of this tj-pe should not purchased at any price. Tonic Feeds. — The so-called conditioners, tonics, or stock feeds are not needed, though the majority of them are harm- less. They frequently consist of inert materials to which have been added such common and cheap ingredients as common salt, sulphur, charcoal, alum, copperas, Epsom salts and Glauber's salts, occasionally with aromatic substances" such as fennel and anise seed. When the low cost of the ingredients is considered, the prices asked for the majority of stock tonics are exorbitant. If they fulfilled the claims made regarding their curative prop- erties such prices might be justified. However, they do not fulfill such claims. An idea of their low initial cost and impo- tence as cure-alls can be obtained from a knowledge of the fact that some of them contain as much as 85 per cent of common salt. Some of the feeds called tonics do have medicinal proper- ties, but it is a slur on the common sense of the stock-owner to ask him to believe that one highly odoriferous powder will cure all animal ills. Such a claim is especially preposterous in the light of the fact that specific ills require specific treat- ment, and even animals have their own individual require- ments in health as well as in sickness. Stock tonics should not be purchased at any price, for the simple reason that an animal in good condition needs no tonic, and an individual that is off feed or otherwise out of order can be treated by cheaper and more effective methods. All proprietary feeds should be bought on the basis of their digestible nutrient content and not on the claims made for them. Where possible, a statement of the constituents from which the mixture is made should be obtained, as this is very frequently a good indication of the probable value of the feed. PART V FEEDING PRACTICE CHAPTER XVIII GENERAL FEEDING CONSIDERATIONS In feeding the dairy herd the greatest attention is necessary in the care of the milking cow and the young calf. Much care is demanded by members of these groups which is not abso- lutely necessary in the case of other animals. The main problem is the same throughout — that of getting maximum results at the lowest cost possible. Consequently, many of the problems mentioned here will apply to other classes of dairy stock in addition to the milk cow. Each cow has her own individual requirements for mainte- nance and production; moreover, attention must be paid to the likes and dislikes of the animals if the maximum or most profitable production is to be obtained. The cow should receive an abundance of feed containing plenty of nutrients in the correct proportions and made up of feeding stuffs that she Ukes. The consideration of economy is essential, in view of the relatively high prices generally demanded for certain types of feeding stuffs. In the major portion of the dairy regions, and especially in the corn belt, the chief feeds that have to be purchased are high protein concentrates, and in buying these the relative cost of the digestible protein in the various feeds should be determined and considered. Other things being equal, the concentrate providing digestible crude protein at the lowest cost per pound should be purchased. The feed of a cow must be regulated by her production, live weight and condition. Enough feed should be provided to keep the cow producing to the best of her ability and in fair 171 172 GEXER/VL FEEDING CONSIDERATIONS condition. She should not be allowed to become poor or too fat. When poor in condition the cow is evidently not getting enough feed for both maintenance and production and is drawing on her body for nutrients to keep up her milk yield. This cannot go on indefinitely, however, and when the body stores of nutrients have been depleted to a certain le\'el milk production must be curtailed. Excessively high condition, except at the beginning of the lactation period, also causes a decrease in milk production. The production of a cow should be determined by means of the milk scales and the Babcock tester, and with their " ad- vice " the feeding operations can be conducted intelligently. As a rule the grain ration will be determined by the produc- tion, and the roughage ration by the live weight of the cow. One pound of grain can generally be fed for each 3 to 4 pounds of milk produced, depending on the richness of the milk and the total amount produced. Another simple method of determining the grain requirements is to allow 7 pounds of grain for each pound of butter fat produced. High- producing cows require more grain than do low producers. As a rule the amount of roughage required per thousand pounds live weight will be about equal to 25 to 35 pounds of silage and 10 to 15 pounds of legume hay per day. The live weight of a cow is a good index as to whether she is being properly fed or not, but good judgment or, better yet, accurate scales must be used in determining the live weight. The weight of a cow varies considerably from day to day and at different times during the day, largely because of dif- ferences in intestinal fill and in the length of time before or after feeding and watering. The weight of a cow should not be expected to remain constant throughout the lactation period, as under average conditions she will decrease in weight for the first six to twelve weeks after calving. This post-parturient live-weight GeneryVL feeding considerations 173 decrease depends largely on the condition of the cow at the time of freshening and on her inherent abihty to take the stores of fat from her body and use them for milk production. The greater this ability is, the greater will be her decrease in weight after freshening; in some cases it amounts to 200 and occasionally even to 500 pounds. After this initial loss, the cow will remain practically constant in live weight for some time, depending largely on the time of her next freshening. For a period of from two to five months previous to calving the cow may be expected to increase in weight. Only a small portion of this increase, however, is due to the growth of the fetus, the remainder being due mainly to the storage of body fat which will later be used for milk production. Heifers during their first and second lactation periods require heavier feeding proportionately than do mature cows. The very obvious reason for this is the growth of the animals. The Guernsey cow, Imp. Parson's Snowdrop IV, at Iowa State College, averaged 872 pounds in live weight in her first lacta- tion period, and during her fourth period of production she weighed, on the average, 1053 pounds. This shows an increase of 21 per cent in live weight; nutrients must be supplied in the ration to take care of this growth and to build up new body tissues. After the fourth lactation the weight of this cow remained fairly constant from year to year, though in the case of some cows full growth may not be reached until a somewhat later age. A cow with a beefy tendency generally requires a ration of a narrower nutritive ratio than does one possessing the nervous temperament so much sought. Two Holstein cows at Iowa State College, Snowflake Josephine DeKol II and Lucy Duchess DeKol, were of practically the same age and had always received the same general treatment, but Snow- flake Josephine DeKol II had a decided tendency to put on 174 GENKK.M. FEEDING CONSIDER.VnONS body fat while Lucy Duchess DeKol showed much greater refinement and was difficult to get into high condition. On one occasion when they freshened at about the same time, Snowfiake Josephine DeKoI II received a ration with a nutritive ratio of i : 4.2 for a part of her lactation period while for a similar period the ration of Lucy Duchess DeKol had a nutritive ratio of i : 5.0. Even with such rations, Snowfiake Josephine DeKol II remained in much higher con- dition than did the other cow. This is due to the fact that the cow with her milk-producing ability well developed tends to use her feed for milk production while the animal with this power less highly pronounced tends to use the feed for the production of body fat; consequently the beefy animal must have this tendency counteracted, as far as possible, by the feeding of extra protein to stimulate milk production, while the other animal must be fed an additional amount of carbohydrates and fats in order that her store of body nutrients may not be depleted to a considerable degree. T.\BLE XTII Increase in Lae Weight Due to M.aturity of Guernsey Cow, Imp. Parson's Snowdrop IV Lactation Age at Freshening .\\-erage Live Weight Pounds I 2 3 4 2 yr. 5 mo. 3 yr. 6 mo. 4 yr. Q mo. 5 yr. 9 mo. 872 966 1018 1053 Though liberal feeding is essential, overfeeding must be strictly guarded against, as it will cause a considerable amount of damage. A very good example of this is obtained from part of the feed and production record of the Iowa State College Guernsey cow, Imp. Rouge II of the Brickfield. GENER.KL FEEDING CONSIDER.\TIONS 175 Milk Pro- duced. Pounds. U-, .0 o c. f) o O tr: N vo fo %^s^.r;^ :? ^ ^ ?: %i^% a a < Total Rough- age. Pounds. Total Concen- trates. Pounds. 1^ 1^ t^ t- M ■- " t- Alfalfa Hay. Pounds. Occooooooaooooo Corn Silage. Pounds. OOOOOOO'O'OLOio Dried Beet. Pulp. Pounds. — — Ground Oats. Pounds. ^ -t -1- ^ f) " <-) <^ up of feeds which, in general, have to be purchased. These are the concentrates of high protein content. The ration may be satisfactory in every other way, but for good producing cows an extra supply of protein will be necessary in addition to that contained in the group just mentioned. As a general rule, this extra supply of protein can only be provided by such factory by-products as cottonseed meal, linseed-oil meal, peanut meal or gluten feed. The advantages of providing this extra feed can again be illustrated by the results obtained in an Iowa herd under the supervision of a cow-testing association. In the first year the cows had silage, mixed hay and pasture for roughage, and throughout the year the only grain allowance was 495 pounds of ground oats per cow. In the second year the silage was increased somewhat, while the hay allowance and the pasture season were reduced. The most marked change was in the grain ration, however, which was increased to an average of 1 183 pounds per cow of a mixture of ground oats, cracked corn and bran, with an additional average allowance of 219 pounds of cottonseed meal. These are the average allowances, but in the second year each cow was fed according to production. As a result of this the average production of the herd was increased from 304 pounds to 418 pounds of butter fat, and though the feed cost was increased from $53 to $83 per cow, the returns over feed cost increased from $129 per cow in the first year to $218 in the second. CHOICE OF PROTEIN SUPPLEMENTS As the main class of feeds that has to be purchased on the average dairy farm is the group of high protein supplements, 248 FEEDING ECONOMY some consideration is necessary in their choice. The main point to which attention must be paid in the purchase of these concentrates is the cost of the digestible protein present, as this is the constituent for which these feeds are primarily purchased. The digestible carbohydrate equivalent in the various con- centrates is practically of uniform value, pound for pound, for feeding purposes, no matter what is the source of the feed. In calculating the cost of the digestible crude protein, a uniform value of i cent per pound can be placed on the diges- tible carbohydrate equivalent. From the cost of loo pounds of feed is subtracted the value of the digestible carbohydrate equivalent, and the difference, when divided by the percentage of digestible crude protein present and multiplied by too, gives, in dollars and cents, the cost of IOC pounds of digestible crude protein in the given feed at the price stated. The Appendix Table IV, on the cost per hundred pounds of digestible crude protein in some common concentrates at various prices has been prepared in this maimer. In comparing feeds in this way a few important factors must be taken into consideration. The feeds under consideration should always be compared on the basis of the prices including freight charges as this frequently is an important item. Some feeds are not used as a source of protein, but for the furnishing of energy- providing materials, and so cannot be compared on this basis with the feeds of high protein content. Consequently it is not possible to compare such concentrates as corn-and-cob-meal and hominy feed with hnseed-oil meal or cottonseed meal. Granting that the feeds which provide protein at least cost should generally be purchased when protein is wanted, yet there are circumstances under which this rule must be somewhat modified. Where the rations contain no succulent feed such as silage, cottonseed meal should not be used, but linseed-oil CHOICE OF PROTEIN SUPPLEMENTS 249 meal will fit in admirably under those conditions and so should be used rather than the cottonseed meal even if the cost of protein is somewhat greater. Then again, when the ration consists largely of corn silage and corn, it is not the best policy to use corn-gluten feed for the protein supplement, it being better to use feeds from some other source than the corn plant in order to give greater variety to the ration. With these limitations in mind, however, it is always well to pur- chase the protein supplements on the basis of the protein they contain. CHAPTER XXX DIGESTIVE DISTURBANCES Dairy cattle, like other forms of live stock, are subject to disease; and though the general problem of derangements of health belongs to the field of. the veterinarian, the man in charge of dairy cattle should be able to detect trouble when it arises and to call in a veterinary practitioner before it is too late. Digestive disturbances are quite common among dairy cattle; and as the man in charge of the stock can usually control these by his feeding methods, attention to a few of them may not be out of place. Indigestion and similar troubles which pass under the same name in both calves and older animals have to be treated differently with the two classes of stock, and will therefore be given separate consideration. CALVES Calves, especially in the early stages of their development, are subject to a few common digestive troubles. These lead to general unthriftiness and, if not properly handled, to a fairly high rate of mortality. These derangements are amen- able to treatment and should be recognized by the man in charge. White scours will not be considered, as it is not of digestive origin, though some of its chief manifestations are in the digestive tract. Prevention is undoubtedly the best treatment for calf troubles, and with careful feeding and management and 250 CALVES 251 reasonable sanitary precautions considerably less trouble is experienced with the more common digestive disturbances of calves. Constipation. — The young calf requires the colostrum, or first milk, of its dam to assist in getting the intestinal tract in good working order. If the calf does not get the colostrum, he may become constipated. Improper feeding, such as lack of sufficient roughage, in older calves may also bring about constipation. One of the safest treatments for constipation is to administer castor oil in doses of i to 3 ounces, depending on the size and age of the calf. The young calf should be watched carefully until it is certain that the bowels are in working order. Indigestion. — In the cases of calves, indigestion may be due to one or more of a variety of causes. Among the more conmion of these are constipation, overfeeding, irregularity in the time of feeding, carelessness in the amount and quality as well as in the temperature of the milk fed, the feeding of dirty milk or other feeds that are in bad condition, too rapid changes in the amount or nature of the feed, or chills brought on by draughts or by cold, damp floors. The cause of the trouble should be immediately located and remedied, and in addition the feed should be cut down and castor oil adminis- tered. Where abnormal fermentations, due to dirty milk, are the cause of indigestion, the administration of limewater frequently aids in bringing relief. Bloat. — This form of indigestion is generally due to ab- normal fermentations in the stomach, brought about by dirty milk, or to the calves sucking each other and thus drawing air into their stomachs. The swallowing of the foam some- times found on separated milk is also a cause, and any of the causes of indigestion may ultimately result in bloat. Castor oil should be administered after the elimination of the cause, and the feed allowance should be reduced. Sometimes a 252 DIGESTIVE DISTURBANCES teaspoonful of ground Jamaica ginger given in hot water will be valuable in giving relief if the bloat is severe enough to cause colic. The ginge^ also has a tonic effect on the stomach and aids in rapid recovery. A drench of lo cubic centi- meters of conmiercial formalin in half a pint of water is also a convenient remedy for bloat. Common Scours. — Though easily prevented by proper care and feeding, common scours are all too prevalent among dairy calves. Any of the causes given for the digestive disturbances already mentioned may ultimately result in scours, and another cause is the feeding to young calves of milk that is too rich in butter fat. When calves are comfortably housed and properly fed and cared for, there should be Httle trouble from common scours. As ordinary scours is a simple digestive derangement, the treatment given should be such as will bring the digestion back to normal. Remove the cause of the trouble, and at the same time cut the milk ration down by at least one-half. This relieves the digestive system, and it can be assisted in freeing itself of obnoxious materials by the administration of i to 3 ounces of castor oil. Treating with formalin also gives beneficial results. A stock solution of i part of commercial fonnalin to 3 1 parts of water is made, and a teaspoonful of this mixture is added to each pound of milk fed. The formalin acts as a disinfectant, destroying the putrefactive organisms which induce the scours. Another satisfactory method of control is to mix 50 grains of salol, if drams of bismuth subnitrate, and 2 drams of sodium bicarbonate, and make into five powders. One of the powders is given in milk every six hours. When the trouble is under control, the calf should be brought slowly back on to full feed. Where the calf is very weak and will not drink, it can be kept nourished by the occasional administration of an egg. The shell of the egg is MATURI-; STOCK 253 cracked, and the egg, shell and all, put well back in the calf's mouth. If the calf's mouth is kept closed he will break and swallow the egg. MATURE STOCK The number of digestive disturbances of mature stock which are commonly met with are quite limited. The main problem is keeping the cows on feed. There are but three digestive troubles which need be mentioned. Indigestion. — There are many causes which lead to in- digestion, but the more common contributory causes are over- feeding, spoiled feed, and sudden changes in the ration. When indigestion occurs it will be noted that the cow is dull and lacks appetite, while the feces are very dry and small in amount or almost entirely absent. In cases, however, where the causal factor is some irritant substance, purging may occur. Treatment consists of cutting down the ration and feeding bran mashes in place of grain. Sometimes this is all that is necessary, but frequently the administration of purgatives is essential. Useful j)urgatives, to be given as drenches, are the following: i to t| pounds of Epsom salts in 2 quarts of warm water; i pound of Epsom salts and i pound of molasses in 2 quarts of warm water; or i to i| quarts of raw linseed oil. The last is the mildest in action. Where Epsom salts are given, it is well to try to induce the cow to drink considerable quantities of slightly warmed water. This hastens the action of the purgative. When the action of the purgative is appar- ent and the appetite of the cow is returning, she should be brought back to full feed slowly, the grain ration being limited for a time and bran mashes fed. Blodt. — The accumulation in the rumen of gas liberated through the influence of bacterial action on soluble food con- stituents, especially carbohydrates, leads to bloat. It occurs 254 DIGESTIVE DISTURBANCES most frequently when animals are pastured on clover, alfalfa or other legumes, and is especially prevalent when these crops are young and succulent. Other young crops will also bring about this condition. Bloat from this cause can be prevented to a considerable extent by having the animals fairly well filled before they are turned out to pasture, and the pasture should not be wet when the animals go on. A good feed of hay before the animals are turned out is quite satisfactory as a preventive measure in many cases; but where there is danger of bloat on pasture the animals should be allowed to remain out only a short time daily for the first few days. As they become accustomed to it the length of time on pasture can be gradually increased. When soiling is being fed in the barn, bloat is rare; but it does occasionally occur under those conditions. Overfeeding on any feed, and digestive disturbances accompanied by excessive fermentation will also result in bloat. There is a characteristic swelling of the left flank in the case of bloat, and this may extend up to the back bone; in some cases the distended rumen may appear higher than the level of the back. The animal is restless and apparently ui distress. In advanced cases breathing is labored and the animal may stagger and fall. Death may occur from suffoca- tion due to the pressure of the rumen on the diaphragm inter- fering with respiration. Rupture of the stomach may also occur. There are many methods of treatment pursued in cases of bloat, or tympanitis, and a few of the more conmion ones are as follows: 1 . The bloated animal is kept moving. This leads to move- ment of the rumen and aids in the liberation of gas. In slight attacks this is occasionally all the treatment that is necessary. 2. A stick — a piece of a fork handle is satisfactory — is put in the mouth of the animal, as is a bit, and the ends of it are MATURE STOCK 255 tied to the horns of the animal or to a halter. The animal chews on the stick, and in the process gas is hberated and the t>Tnpanitis relieved. This process is aided by standing the animal with the fore feet at a higher level than the hind ones. 3. The introduction of a rubber tube through the mouth to the stomach sometimes gives relief. This, however, is occa- sionally difficult to do and it is not satisfactory in all cases. 4. A number of drenches are recommended for bloat. Two that are satisfactory and easily prepared are: 3 ounces of turpentine in i pint of raw Unseed oil; half an ounce of formalin in i quart of water. Either of these will bring relief fairly readily, but they will be aided in their action by tying a stick in the mouth of the animal. When the bloating has subsided it is frequently advisable to give the animal a purgative to clean out the digestive tract and prevent the recurrence of the trouble. A suitable drench is i pound of Epsom salts and i§ ounces of ground Jamaica ginger in 2 quarts of warm water. The Epsom salts remove the material that has been causing trouble and the ginger has a tonic effect. 5. When the bloat is very severe and there is danger of the animal collapsing before any of the methods mentioned could be effective, piercing with a trocar and canula must be resorted to. The point at which the trocar should be inserted is equidistant between the last rib, the hip bone and the lumbar vertebrae. The trocar should be pushed downward, inward and forward, and as it is withdrawn the canula should be left in place to allow the gas to escape as it forms. When the gas ceases to form the canula may be withdrawn, but the animal must be watched to see that the use of the trocar is not again necessary. It is usually best to cork the canula at intervals, as the formation of gas can be easily detected when the cork is withdrawn. The trocar and canula should be disinfected before use. 256 DKiESTIVK DISTURBANCES The treatment of bloat is simple; but oeeasionally animals will be found which bloat habitually with little or no provoca- tion. Such individuals should be disposed of. Impaction. — The rumen of the cow has a large capacity, but at times when it is not functioning properly a large amount of feed may become lodged there and cause distention. This condition, known as impaction, is easily distinguished from bloat. In the case of bloat, if the enlargement be pressed in, it will at once return to its original position when released; but in the case of impaction some httle time will be required for this to take place. Impaction is largely induced by overfeeding, cspecialh' of dry feeds such as hays and grains. The first step in treatment is consequently to stop feeding. Then when the excess of material in the rumen has started to pass on a purgativ^e should be given. Any of those mentioned are good, and it is well also to give ginger. The return to full feed should be gradual. This simple treatment is generally effective, but in some cases veterinary assistance is needed. PART VI APPENDICES APPENDIX I DIGESTIBLE NUTRIENTS IN FEEDS The content of digestible nutrients given here for the various feeds is taken by special permission from the extensive data in Appendix Table III of the seventeenth edition of " Feeds and Feeding " by W. A. Henry and F. B. Morrison. Only feeds that are of special interest in the feeding of dairy cattle and a few that are of note on some other accounts are included. The method of using this table is outlined in Chapter VIII. 259 200 APPENDIX .1 APPENDIX TABLE I Digestible Nutrients in Feeds Feed Succulent Roughages Silage: Corn, mature Corn, immature Corn stover Corn cannery refuse . . . . Sorghum Alfalfa Clover Soybean Corn and Soybean Green Forage: Alfalfa Clover, red Clover, Alsike Sweet clover Peas Cowpeas Soybeans Corn fodder Sweet-corn stover Oats Rye Millet, common Sorghum Oats and peas Bluegrass Roots, Tubers, etc. Sugar beets Mangels Turnips Rutabagas Total Dry Matter, Per Cent 26.3 21 .0 19.6 16.7 22.8 24.6 27.8 27.1 24.7 25-3 26.2 24-3 24.4 16.6 16.3 23.6 21 .9 21.5 26. 1 21.3 27.6 24.9 22.6 31-6 16.4 0-4 Q-5 10.0 Digestible Nutrients Crude Carbo- Fat, Protein, hydrate, Per Cent Per Cent Per Cent I.I I5-0 0.7 I.O II. 4 0.4 0.5 9.9 0.4 0. 1 4-9 0.1 0.6 II. 6 o-S 1 .2 7.8 0.6 1-3 Q-5 0-5 2.6 II .0 0.7 1.6 13.8 0.8 3-3 10.4 0.4 2.7 13.0 0.6 2.7 II. 8 0.4 3-3 10.3 0-3 2.9 71 °-3 2-3 8.0 0.3 3-2 10. 2 0-5 1 .0 12.8 0.4 1.0 131 03 2.3 II. 8 0.8 2.1 12.2 0.5 1.9 14.8 0.6 0.7 14. 1 0.6 2.4 10.6 0.6 2.3 14.8 0.6 1 . 2 12.6 0.1 0.8 6.4 0.1 1 .0 6.0 0. 2 1.0 7-7 03 DIGESTIBLE NUTRIENTS IN FEED APPENDIX TABLE I— Continued 261 Feed Total Dry Matter, Per Cent Digestible Nutrients Crude Protein Per Cent Carbo- hydrate, Per Cent Fat, Per Cent Succulent Roughages Continued Roots, Tubers, etc. — Continued Beet pulp Potatoes Pumplcins Dry Roughages Alfalfa.-. Clover, red Clover, Alsike Sweet clover Pea Cowpea Soybean Corn fodder Corn stover Oat straw Timothy Millet, common Sudan grass Sorghum fodder Oat and pea Concentrates Corn, shelled Corn meal Corn-and-cob meal Hominy feed Germ-oil meal Corn bran Gluten meal Gluten feed Corn distillers' grains Ground oats 91.8 21.2 8.3 10.6 7.6 7-9 10. q 8.3 7-5 6.9 6.1 7.0 16.5 5.8 30.2 21.6 22.4 Q 4 65.2 15.8 4-5 I.O 42 30 42 so 46 3-3 53 67 8 4 69 3 63 7 3 61 2 7 42 6 10 56 9 4 43 9 4 51 9 3 40 4 II 51 4 4 0.8 0.9 1.8 1 .1 0.7 1.9 1 .0 1.2 1-5 1.8 0.9 262 APPENDIX I APPENDIX TABLE I— Continued Feed Concentrates — Continued Wheat Wheat bran Wheat middlings Flour- wheat middlings Red Dog flour Barley Malt sprouts Brewers' grains Rye Rye distillers' grains Rice Kafir Milo Peas Cowpeas Soybeans Soybean meal Peanut meal Peanut feed Cottonseed meal Cold-pressed cottonseed cake Flax seed Linseed meal, O. P Linseed meal, N. P Coconut meal Palmnut meal Buckwheat Molasses, cane Dairy Products Whole milk Skim milk Buttermilk Whey Total Dr>' Matter, Per Cent 89 Digestible Nutrients Crude Protein, Per Cent Carbo- hydrate, Per Cent 9.2 12.5 13-4 15-7 14.8 9.0 20.3 21-5 9.9 13.6 4-7 9.0 8.7 19.0 19.4 30-7 38.1 42.8 20.2 37 o 21 . 1 20.6 30.2 31-7 3-3 3.6 3-4 0.8 Fat, Per Cent 64.6 65.8 66.2 55-8 54-5 22.8 33-9 20.4 16.0 21.8 33-2 17.0 32.6 37-9 42 .0 45-8 49-7 58.2 4-9 51 4-9 4-7 1-5 30 4-3 4-3 3-5 1.6 1-3 6.1 1 .2 6.6 1-7 2-3 2.2 0.6 0.1 0-3 Total, Per Cent APPENDIX II A FEEDING STANDARD FOR DAIRY COWS All present-day feeding standards are moditications of the original Wolff-Lehmann Standard. The one presented here has been prepared by Morrison and is taken by express per- mission from the tables in the eighteenth edition of ' 'Feeds and Feeding," by Henry and Morrison. It has one great advantage in that only two units are used, digestible crude protein and total digestible nutrients. In addition, a minimum and maximum is given in each case. The maxima are for use with high producing cows and the minima for low producers. A variation in the relative amounts of protein and total nutrients is also provided. This is due to the fact that, in general, protein is more expen- sive than other nutrients and so should not be fed to excess, while at other times feeds of high protein content are rela- tively low in price and so can be fed in greater quantities. In certain sections also, especially in the south and in the west- ern alfalfa regions, the feeds of relatively high protein content are generally cheap. The method of using this standard is explained in Chapter VIII. 263 204 [j tr/lJ^'tii APPENDIX II APPENDIX TAI5LE II A Feedinc. Standaku for Dairy Cows Dif.n-stible Total Crude Dik'estible Protein, Nutrients, Pounds Pounds Dairy Cows: For maintenance of looo-lb. cow . 7C0 7.925 To allowance for maintenance add : 4 For each pound of 2 . 5 per cent milk 0.045-0.053 0. 230-0. 256 For each pound of 3 per cent milk 0.047-0.057 0.257-0.286 For each pound of 3 5 per cent milk 0.049-0.061 0.284-0.316 For each pound of 4 per cent milk 0.054-0.065 O.311-O.346 For each pound of 4 5 per cent milk 0. 057-0. o6q 0.338-0.376 For each pound of 5 per cent milk 0.060-0.073 0.362-0.402 For each pound of 5 5 per cent milk 0.064-0.077 0.385-0.428 For each pound of 6 per cent milk 0.067-0.081 0.409-0.454 For each pound of 6 5 per cent milk 0.072-0.085 0.434-0.482 For each pound of 7 per cent milk 0.0 74-0. o8q 0.454-0.505 <^ ^ APPENDIX III >^. i' - . '^ MINERAL ELEMENTS IN FEEDS The mineral or ash content of feeds has an important bear- ing on their value, especially for the growth of bone and for milk production. Little work on this problem has really been accomplished. The figures in the accompanying table are selected from " Mineral and Organic Analyses of Foods," published as Bulletin 255 of the Ohio Agricultural Experiment Station, by E. B. Forbes and others in 1913. Some of the important facts to note are the amount of total ash, and the amounts of calcium and phosphorus which are used in bone-building. The excess of base and the excess of acid are also worthy of attention. All other data are given on the percentage basis; but the excess of base is expressed in the number of cubic centimeters of normal acid solution that is requirefl to neutralize the excess base in 100 grams of the dried material. The excess acid is likewise expressed in terms of the number of cubic centimeters of normal solution of alkali required to neutralize the excess acid in 100 grams of dried material. It may be noted that all of the concentrates studied, with the exception of wheat bran, linseed-oil meal and the legumes, contain an excess of acid, while all of the roughages listed are basic in character. 265 266 APPENDIX III a o u w " o 03 O CO JJ c s 5 §u O O ^O t^ Qs t^ t~-0\0>J^Ot^i-i-^0^'i'" OOrO O^ love OOOmOOwOOOO rOMMWMMM OO vo li->vO 0^ O ":i »o HMHMMMCOM VOOMTl-OO'Na-'t^ 1-4 '+00 \0 fO -^ O t^ H Tf Tt rt CS 00 r~.MOO CD(N O rO"+ CO CO fOO 00 tJO 00 t^ O O^O M OsOOvOro0 Q ^ .:- a.;:^ rt rt O s a o a ■o o N O -Ot^OO'^OO OONO lOOO t^ C> w roco lO t^ M O 00 -^OO CO O >0 (N M C On On O to t-t O '^ t^ to o O'^oo o t^t-i Tj-vooo <^i t^po^; o t%. M 1-1 t^ »D O 'i- 'i- t- M rooo o rOOO 00 00 00 5 ^^8 8 lOt^^^ t^Ov«^0 vo O M M in O- 1-- o o no OO HVOOO lOM lo-t w lO w OnnO ? l^ O. M to o ■* On NO On O O irivo lo O00 ONOO >o On NO On OnnO ^2^a{^5.cZ~'S;2^g ro O t~" to O to ^ O t- M >o ^^^S O OllOMt^u-lOw tN rf t^oo (^ o t^ O t- O t^-O ^00 o o t^ ^ ^ -* -t (^ lO t^ t-~ Tj- OcocoO O 00 "N to O O OO to to to t^ M r^ i^ 00 '^no r- CO to 't O to -* <^ ^ to T)-vO t^ O O <-l ioo -^M cJ^O0 to t^ Tj- t--0O t- CJ NO O 't R O 00 On t^ 0 rO >0 roO r-00 On M M M to to ^ lO lO to O O '^ t^vC lO t^ •^ t^ to ■* r-NO M CNCN, to ONt. s t^ Jo ^ 5- O tN Tt- M Tj- ro >00 I-- 00 O O On to -o to to to to t^ O On '^r M Ov 000 o t-00 ON O.00 * ■* C '3= o o o o o -• -• = ^-S^-l£ "s' ^ J i uuuffiC003i::S^003auu j INDEX Abomasum, 38, 39, 41, 42 — , digestion in, 41 Absorption, 36, 44, 45 Accessories, food, 34 Acids, amino, S3, 34, 43. 44, 62, 93 — , essential, 62 fatty, S3, 43, 44 in silage, loi nucleic, 44 Age, influence on balance of nutri- ents, 83 — , ■ live weight, 1 74 — , response to feeding, 18 Albumin, 34 Alfalfa, 55"^ — hay, 129 y/ — meal, 130 "^ — molasses feeds, 164 — pasture, 124 — silage, log — soiling, III Allowance of grain, 172 roughage, 172 Alsilvc clover, hay, 131 -soiling, 113 Amber cane and cowpcas for soiling, 120 soybeans for soiling, 1 20 silage, 108 soiling, 117 Amino-acids, 33, 34, 43, 44, 62, 93 — , essential, 62 Amylase, 43 Anti-neuritic vitaminc, 55 Anti-scorbutic vitaminc, 56 Apple pomace silage, 109 Arginine, 62 Arterial blood, 44 Ash, 27, 28, 31, 35, 58 — •, functions of, 58 — • in corn, 137, 141 — , influence on production, O3 — ■ requirements, 82. Asparagin, 34 Asparagus, 3^ Bacteria in digestion, 40, 41 Balance of nutrients, 8i — ■, as influenced by age, 83 — ■ — ■ — • condition, 84 ■ individuality, 87 quality of milk, 85 — • ■ size, 83 — • stage of lactation, 86 • — yield of milk, 85 Barley, 145 — and peas for soiling, 1 20 — bran, 146 — ■ brewers' grains, 146 — -, grinding of, 240 — ■ malt sprouts, 146 — , rolling of, 240 — • shorts, 146 — straw, 133 — ■ soiling, 118 Beans, 55, 151 Beets, 55, 56 — , molasses, 161 — , pulp, 125, 241 — , — silage, 109 2b9 270 INDEX Beets, sugar, 55, 124 — , top silage, 109 Beri-beri, 55 Bile, 43, 45 Birth weights of calves, 215 Bladder, gall, 43 Bloat, 113, 124 — in calves, 251 — ■ — mature stock, 253 Blood, arterial, 44 — -, dried, for calves, 224 — ■ meal, 163 — , venous, 44 Bluegrass pasture, 122 Bone, 28 Bran, barley, 146 — , buckwheat, 160 — ; corn, 141 — •, mash, 93, 241 — , oat, 143 — , peanut, 152 — , rice, 148 — , rye, 147 — , wheat, 56, 89, 130, 144 Breeding, influence on production. Brewers' grains, 146 Buckwheat, 160 — ■ bran, 160 — ■ hulls, 160 — ■ middlings, 160 — straw, 134 Bulk, 94 — ■, influence on digestion, 94 Butterfat, fat-soluble A in, 55 Buttermilk, 162 — ■, dried, 162 — , — •, for calves, 217 — ■ for calves, 216 Cabbage, 55, 56, 98 Caecum, 42 Calcium, 28, 29, 35 Calf feeding, 212 ; buttermilk, 216 Calf feeding, chalk, 224 •, charcoal, 224 ■, condiments, 224 — — , dairy by-products, 216 — — , digestive disturbances, 250 , dried blood, 224 — ^, dried buttermilk, 217 , dried skim milk, 217 , early treatment, 212 , grain, 218 , — , grinding, 219 , — ■ mixtures, 219 •, — ■, self-feeding, 219 •, hand-feeding, 214 hay, 221 — , necessity of, 221 milk, skim, 216 — , substitutes, 217 — , supplements, 217 — •, whole, 215 — , ^, inefficiency of, 221 pasture, 223 rock phosphate, ground, 224 roots, 223 salt, 224 silage, 223 teaching to drink, 213 water, 224 whey, 216 Calves, birth weights, 215 — , necessity of bulk, 221 —, necessity of vitamines, 54 Cane molasses, 161 Capillaries, 44, 45 Carbohydrates, 32, 33, 52 — ■, digestion of, 40 ^, equivalent, digestible, 49 — , functions of, 52 — , influence on production, 60 Carbon, 25, 32, 5^ Carotin, 35, 56 Carotinoids, 35, 56 Carrots, 35, 55, 56 Caseinogen, 34 — , digestion of, 42 INDEX 271 Cellulose digestion, 40 Cereals, grains, 136 — , straws, 133 — , water-soluble B in, 55 — , water-soluble C in, 56 Chalk, 28 — for calves, 224 Charcoal for calves, 224 Chlorine, 2q, 35 Chlorophyll, 35, 55 Chopping feed, 241 Chyme, 43, 44 Clippings, oat, 143 Clover, 55 — hay, 130 , Alsike, 131 , crimson, 131 , mammoth red, 131 ■, red, 131 , sweet, 131 — pasture, 124 — silage, 109 — soiling, III •, Alsike, 113 •, crimson, 113 , mammoth red, 113 , red. III ■, sweet, 113 Coconut meal, 159 Coefficient of digestibility, 49 Cold-pressed cottonseed cake, 156 Colon, 42 Common scours, 252 Concentrates, methods of feeding, 238, 239 — , mixed, 164 Condiments for calves, 224 Condition, 47 — , influence on balance of nutri- ents, 84 Constipation, 251 Cooking feed, 242 Com, 55. 136 — and-cob meal, 95, 140 cowpeas for silage, no Corn and cowpeas for soiling, i : — — soybeans for silage, 1 10 — ■ soiling, 1 20 — ash, 137 — bran, 141 — • cobs, 139. — ; cracked, 90, 139 — , dent, 136 — distillers' grains, 142 —, car, 139 —, flint, 136 — fodder, 133 — • germ-oil meal, 141 — gluten feed, 142 meal, 141 — , grinding, 240 — hominy feed, 140 — meal, 139 — oil, 33 — ■, pentosans in cobs, 139 — pigments, 137 — preparations, cost of, 241 — ■ proteins, 137 — , shelled, 90, 139 — ■ shrinkage, 138 — silage, 92, loi , acids in, loi ■, — • — ■, acetic, loi — — ■, — ■ — •, lactic, loi — ■ — • feeding, 100 , rate of, 107 — • — ■ — -, summer, 107 — ■ — ■ ^, winter, 106 • flavor in milk, 107 ■ for conservation, 103 from cannery refuse, 105 fodder, 104 ■ — stover, 104 — • ^, frosted, 103 — — , grain in, 102 -, moldy, 102 , packing, 105 , rotting, 105 — — , value of, 104, 115 — , soft, 138 272 IXDKX Corn soiling, 115 — ■ — , sweet, lis — solubles, 141 — • stover, 133 — , sweet, 136 — vitamines, 137 — , white 55, 137 — , yellow, 55, 137 Cost of protein, 171 Cottonseed, 153, 154 — , cold-pressed cake, 156 — feed, 156 — , gossypol, 153 — hulls, 95, 155 \/ — meal, 89, 97, 155 — poisoning, 153 Cow, feeding of, after parturition, 201 — , , before parturition, 201 — , , dry, 200 — , preparing for parturition, 200 Cowpeas, 151 — hay, 131 — soiling, 114 Cracked corn, 139 Crimson clover hay, 131 soihng, 113 Crude fiber, 32, 52 , functions of, 52 , protein, 34 Cud, 37 Cystine, 62 Deficiency diseases, 54 Dent corn, 136 Dextrin, 38 Dextrose, 38 Digestibility, 49 — , coefficient of, 49 — , influence of bulk on, 94 Digestible carbohydrate equi\alent, 49 Digestible nutrients, 49, 50 Digestion, 36 — coefficient, 49 Digestion, effect of feeds on, 96 — , palatability on, 89 j — in abomasum. 41 — - intestine, 42 large intestine, 43 - ~ mouth, 37 omasum, 41 — — reticulum, 40 rumen, 40 — — small intestine, 42 — — stomach, 38 — , true, 41 Digestive disturbances, 250 , bloat, in calves, 251 ■, — mature stock, 253 — — , common scours, 252 — --, constipation, 231 , impaction, 256 , indigestion, in calves, 250 ^ — ■,—., — mature stock, 253 Distillers' grains, corn, 142 , rye, 147 Dried blood, 224 — iiuttermilk, 162 — milk, 162 — ■ skim milk, 162 Dry matter, 31 , inorganic, 31, 35 , organic, 31 — stock, feeding, bulls, 227 — —, — ■, — , silage for, 228 — — , — , cows, 200 ^ — ■, — , heifers, 225 Duodenum, 42, 43 t^urra, 148 Dust, oat, 143 E Ear corn, 139 Economy of feeding, 171, 243 — — — , choice of protein supple- ments, 247 • — , individual feeding. 243 , Uberal feeding, 245 — , protein supply, 247 , use of home-grown feeds, 245 INI EX 275 Energy, 50 — , gross, so — , heat, 50 — losses, 50, 51 — , metabolizable, 57 — , net, 51 — values, 50 Enterokinasc, 43, 44 Enzymes, 38, 40, 41, 42, 43, 44, 45 — , amylase, 43 — , erepsing, 44 — , gastric lipase, 41, 42 — , invcrtasc, 44 — , inverting, 44 — , lactase, 44 — , lipase, 31, 42, 43 — , maltasc, 38, 44 — , nuclease, 44 — , pepsin, 41, 42, 43 — , ptyalin, 38 — , rennin, 41, 42 — , secretin^ 43, 44 — , steapsin, 43 — , trypsin, 43 Equivalent, digestible carboh\ dratc, Erepsin, 44 Ether extract, ^s Extract, nitrogen-free, 32, 33, 52 — , , functions of, 52 — , ether, 35 F Faeces, 45 Fat, 32, 33, 44, 53 — , crude, 33 — digestion, 42, 44 — , functions of, 53 --, influence on production, 61 — -, — ■ — quality of milk, (n — , percentage, high, feeding for, 2 — soluble A, 34, 55 , functions of, 55 , sources of, 55 — , true, 33 Fattening, 47 Fatty acids, 33, 42, 43, 44 Linseed oil, 33 meal, 89, 157 , new process, 158 , old-process, 158 — , test for, 158 pase, 41, 42 — lochrome, 56 — ?r, 43 — , weight, influence of age on, 174 - , ph, 44 — , phatics, 44 —, tG 52 — uni I'ccdin; M — , influm, 28, 35 — , ice, 46 — methoS, 42, 43, 44 , con, 44 , ordts, 146, 241 -, regufd clover, for hay, 131 — — , roughoiling, 113 — standards 24 based oi eni24i gros8 tota, , criticisms, ', , development Feterita, 148 — fodder, 134 — soiling, 118 — stover, 134 Fetus, growth of, 48 Fiber, crude, 32, 52 — , functions of, 52 Fillers, 167 Fishery by-products, 163 , fish meal, 163 , whale meal, 164 Flaxseed, 157 — , linseed-oil meal, 157 ^, , new process, 158 — , , old process, 158 — , , test for, 158 272 INI LX Corn soiling, 115 , sweet, 115 — solubles, 141 — stover, 133 — ■, sweet, 136 — \-itamines, 137 — , white 55, 137 — , yellow, 55, 137 Cost of protein, 171 Cottonseed, 153, 154 — , cold-pressed cake, 156 — feed, 156 — , gossypol, 153 — hulls, 95, 1 55 /^/ — meal, 89, 97, 155 — poisoning, 153 Cow, feeding of, after partui — , , before parturitio' — , — — , dry, 200 — , preparing for parturitio Cowpeas, 151 — hay, 131 — soiling. 114 Cracked corn, 139 Crimson clover hay, i soiling, 1 13 Crude fiber, 32, 52 , functions of , protein, 34 Cud, 37 -4 Cystine, 62 owance, 172 DeP ^^^'' ^46 r distillers', corn, 142 -, — , rye, 147 — for calves, 218, 219 — , grinding, 90, 240 — , rolling, 240 — , whole, 90 Grass, 55, 56 — silage, 109 — soiling, 118 , brome, 118 , orchard, 1x9 Grass soiling, red-top, 118 , timothy, 118 Grinding grains, 90, 240 Gross energy, 50 Ground oats, 143 Growth, 47 — of fetus, 48 Gullet, 38 H Hay, 32, 56 — for calves, 221 — , leguminous, 92, 95, 128 — , — , alfalfa, 129 — , — , clover, 130 — , — , — , Alsike, 131 — . — , — , crimson, 131 — , — , — , mammoth red, 131 — — , — J red, 131 — , — , — , sweet, 131 — , — , cowpea, 131 —, — , pea, 131 — , — , soybean, 132 — , mixed, 135 — , — oat and pea, 135 — , non-leguminous, 132 — ■; — , millet, 134 — , — , Sudan grass, 133 — , — , timothy, 131 Heat, 50 Histidine, 62 Hominy feed, 140 Honeycomb, 40 Hulls, buckwheat, 160 — , cottonseed, 155 — , oat, 143 — , rice, 148 Hydrochloric acid, 29, 41, 42, 43 -in gastric juice, 41 Hydrogen, 26, 32, ss Ilcocaecal valve, 45 Ileum, 42 Impaction, 256 INDEX 275 Indigestion in calves, 251 — — ■ mature stock, 252 Individual feeding, 19, 243 Individuality, influence on balance of nutrients, 86 — , production, 14 Influence of age on response to feeding, 18 breeding on production, i individuality on production , 14, 19 liberal feeding on production, 15 " nicking " on production, 1 2 selection on production, 7 Inorganic dry matter, 31, 35 Intestine, 42 — , digestion in, 42 — , large, 42, 45 — , small, 42 Invertase, 44 Iodine, 29 Iron, 28, S3, 35 Jejunum, Kafir corn, 148 fodder, 134 silage, 108 soiling, 118 stover, 134 Kaoliang, 148 — fodder, 134 Lactase, 44 Lactochrome, 58 Large intestine, 45 Legumes, 27, 55, 56 — for hay, 92, 128 silage, 109 soiling. III straw, 132 Liberal feeding, 174, 245 Limestone, 28 Linseed oil, 33 meal, 89, 157 , new process, 158 , old-process, 158 , test for, 158 Lipase, 41, 42 Lipochrome, 56 Liver, 43 Live weight, influence of age on, i Lymph, 44 Lymphatics, 44 Lysine, 52 M Magnesium, 28, 35 Maintenance, 46 Maltase, 38, 42, 43, 44 Maltose, 38, 44 Malt sprouts, 146, 241 Mammoth red clo\er, for hay, 131 , — soiling, 113 Mangels, 55, 124 Manyplies, 41 Mash, bran, 93, 241 Mastication, 37, 38 Meal, blood, 163 — , coconut, 159 — , corn, 139 — , corn-and-cob, 140 — , cottonseed, 155 — , fish, 163 — , germ-oil, 141 — , gluten, 141 — , linseed-oil, 157 — , palmnut, 159 — , peanut, 152 — , soybean, 152 — , whale, 164 Metabolizablc energ>% 51 Middlings, buckwheat, 160 — , flour wheat, 145 — , oat, 143 — , rye, 147 — , standard. 144 — , wheat, 144 27G IXDKX Middlings, white, 144 Milk, 34 — , color, 3S, 56 — digestion, 42 — , fat-soluble A in, 55 — , flavor of corn silage in, 107 — for calves, dried skim, 217 , skim, 216 , whole, 215 — , influence of quality on l>alance of nutrients, 85 — , yield on balance of nutri- ents, 85 — , insufficient for calves, 221 — pigments, 35, 56 — , skim, 162 — -; — , dried, 162 — substitutes, 217 — supplements, 217 — , water in, 52, 233 —, water-soluble B in, 55 — , water-soluble C in, 56 — , whole, 161 — , — dried, 162 Millet grain, 14 — hay, 134 — soiling, 116 Milo, 148 — fodder, 134 — soiling, 118 Mixed hay, 135 — pasture, 1 24 — silage, no Molasses, 160 — , beet, 161 — , cane, 161 — feeds, alfalfa, 165 , peat, 165 Mouth, 37 N Net energy, 51 " Nicking," influence on production, 12 Nitrogen, 27, ^3 Nitrogcn-frcc dxtract, 32, ;i^, 52 . functions of, 52 N'on-leguminous silage, 108 Non-protein nitrogenous coni])ounds, 53 , functions of, 53 , influence on production, 63 Nuclease, 44 Nucleic acids, 44 Nutrients, 31, 44 balance of, 81 , as aff'ected by age, 83 , — • condition, 84 , individuality, 86 — — , quality of milk, 85 , — size, 83 , stage of lactation. 86 , yield of milk, 85 comparison of, 49 digestibility of, 49 functions of, 52 total digestible, 49, 50 transportation of, 52 utilization of, 46 Nutrition, plane of, 63 — , influence on production, 63 Nutritive ratio, 50 Oats, 142, 143 — and peas for hay, 135 silage, no soiling, 119 vetch for soiling, 1 20 — clippings, 143 — bran, 143 — dust, 143 — , ground, 90, 143, 240 — hulls, 143 — middlings, 143 — shorts, 143 — silage, 109 — soiling, 116 — straw, 133 INDEX 277 Oats, whole, 90 (Esophogeal groove, 39, 40, 41 (Esophagus, 38 Oil, corn, SS — , linseed, 141 Oil-meal, germ, 141. — , linseed, 89, 157 Omasum, 38, 39, 41 Orange cane for soiling, 118 Orchard grass for soiling, 118 Order of feeding, 237 Organic dry matter, 31 Overfeeding, 63, 174 Oxygen, 26, 3°> 3^, 33 P Packing-house by-products, 163 , blood meal, 163 , tankage, 163 Palatability, 88 — , influence on digestion, 89 Palmnut meal, 159 Pancreas, 43 Pancreatic juice, 43 Parotid glands, 37 Pasture, 121 — , alfalfa, 124 — , bloat on, 124 — , bluegrass, 122 — , clover, 1 24 — for calves, 223 — , mixed, 1 24 — , Sudan grass, 122 — , value of, 122 Paunch, 39 Pea, 55, 150 — and oats for silage, no soiling, 119 — hay, 131 — vine silage, no Peanut, 152 — bran, 152 — feed, 152 — hulls, 152 — meal, 152 Peat-molasses feeds, 165 Pentosans in corn, 139 Pepsin, 41, 42, 43 Pei)toncs, 42, 44 Phosphate for calves, ground rock, 224 Phosphorus, 28, 53, 35 Phytin, 144 Pigments, 35, 56 — , carotin, 35 — , carotinoids, 35 — , chlorophyll, 35 — in corn, 137 — , influence on production, 63 — , xanthophylls, 35 Plane of nutrition, 63 Poisoning, cottonseed, 153 — , flaxseed, 157 — , sorghum, 118 Polish, rice, 148 Polyneuritis, 55 Potassium, 27, 35 Potatoes, 55, 126 — , sweet, 55 Preparation of corn, 138 and-cob meal, 140 , cost of, 241 , cracked, 139 , ear, 139 , shelled, 139 feed, 240 , barley, 240 , chopping, 241 , cooking, 242 , corn, 240 — , grinding, 240 ■ — , oats, 240 , rolling, 240 ^, — barley, 240 — , soaking, 241 — . — beet pulp, 241 , — bran mash, 241 , — malt sprouts, 241 Prickly pear silage, 109 Production, factors affecting, ash, 63 — , , carbohydrates, 60 278 INDEX Production, factors affecting, con- dition, 63 , fats, 61 , indiN'idual nutrients, 60 ■ , non-protein nitrogenous compounds, 63 , pigments, 63 , plane of nutrition, 63 , — overfeeding, 63 , underfeeding, 66 , proteins, 61 , — , amount of, 61 , — , nature of, 62 , vitamines, 63 requirements for, 76 Products, effect of feed on, 97 Prosecretin, 43 Proprietar\' feeds, 164 — , alfalfa-molasses, 165 — , fillers, 167 — , mixed, 164 — , peat-molasses, 165 — , standard, 164 — , tonic, 168 Protein, 27, 28, 29, 32, ^^^ 34, 42, 53 — , cost, 171 — , crude, 34 — , functions of, 53 — in corn, 137 — influence on production, 61 — supplements, 247 , choosing, 248 — supply, 247 — true, 34 Proteoses, 42, 44 Ptyalin, 38 Pumpkins, 127 Pylorus, 46 Quality of milk, influence of fat on, 6t , overfeeding on, 63 , underfeeding on, 60 , — on balance of nutrients, f'5 Quality of proteins, influence on pro- duction, 62 Rape soiling, 119 , influence on milk flavor, 119 Ratio, nutritive, 50 Rations, formulating, 77 — , winter, 198 Rectum, 42, 45 Red clover hay, 131 soiling, III Red Dog flour, 145 Red-top soiling, 118 Regularity of feeding, 237 Regurgitation, 37, 40 Rennin, 41, 42 Reticulum, 38, 39, 40 Rice, 147 — bran, 148 — hulls, 147 — polish, 148 Rickets, 55 Rock phosphate for calves, 224 RoUing grains, 240 Roots, 32, 55, 124 — for calves, 223 Roughages, allowance, 172 — , method of feeding, 238 Rumination, 40 Rumen, 38 39, 40 Rutabagas, 124 — , influence on milk flavor, 98 Rye, 89, 147 — and vetch soiling, 1 20 — bran, 147 — distillers' grains, 147 — middlings, 147 — silage, 109 — soiling, 156 — straw, 133 S Saliva, 37, 40 — , amount of, 38 — , enzymes in, 38 INDEX 279 Salivary glands, 37 , parotid, 37 , sublingual, 37 , submaxillary, 37 Salt, 27, 29, 233, 23s — for all stock, 235 calves, 224 cows, 235 — , methods of providing, 235 Sand, 30 Scours, common, 252 Secretin, 43, 44 Selection, influence on production, 7 Shallu, 148 — fodder, 134 Shelled corn, 139 Shorts, barley, 146 oat, 143 wheat, 144 Silage, alfalfa, 109 amber cane, 108 apple pomace, 109 beet pulp, 109 — tops, 109 clover, 109 corn, 92, loi — , acids in, loi — , , acetic, loi — , , lactic, loi — and cowpeas, 1 10 — ■ — peas, no soybeans, 1 10 — cannery refuse, 105 feeding, 106 — in summer, 107 — in winter, 106 fodder, 104 for calves, 223 — conservation, 103 — supplementing pastures, 182 frosted, 103 grain in, 102 influence on milk flavor, 107 moldy, 102, 105 packing, 102, 105 Silage, corn, rate of removal, 107 — , — , rotting, 105 — , — stover, 104 — , — , value, 104, 105 — , — , versus soiling, 188 — , — , , comparative value, 190 — , — , , economy of, 189 — , grass, 109 — , kafir, 108 — , mixed, no — , oat, 109 — , pea-vine, no — , prickh- pear, 109 — , rye, 109 — , sorghum, 108 — , soybean, 107 — , sunflower, 108 Silicon, 30, 35 Size, influence on balance of nutri- ents, 83 Skim milk, 162 , dried, 162 for calves, 216 Small intestine, 42 Soaking feed, 241 Sodium, 27, 35 Soiling, III, 182 — , alfalfa, ni — , amber cane, 117 — , barley, 116 — , clovers, II, 113 — , corn, 115 — , cowpeas, 114 — , feeding of, 192 — for supplementing pastures, 182 — , grasses, 118 — , millet, 116 — , oats, 116 — , — and peas, 119 — , peas, 113 — , production of, 191 — , rape, 119 — , rye, 116 — , soybeans, 114 — , Sudan grass, 117 280 IXDKX Soiling systems, 194 — , vetches, 114 — versus silage, 188 — , wheat, 116 Solubles, corn, 141 Sorghum fodder, 133 — grains, 148 — poisoning, 118 — silage, 108 — soiling, 114 — stover, 134 Soybean, 55, 131 — hay, 132 — meal, 152 — silage, 109 — straw, 132 Starch, ^3- 42, 43 — digestion, 38, 42 Steapsin, 43 Sterility, 55 Stomach, 38 — capacity, 39 — compartments, 38 — digestion, 38 — , true, 41 Stover, corn, 133 — , sorghum, 134 Straws, buckwheat, 134 —, cereal, 133 — , flax, 134 — , leguminous, 132 Succus entericus, 44 Sucrose, 44 Sudan grass hay, 133 pasture, 122 soiling, 117 Sugar, S3, 43, 44 — beets, 55, 124 Sulphur, 28, T,s, 35 Sunflower silage, 108 Sweet clover, 89 Sweet potatoes, 55 Tankage, 163 Teeth, 37 Therm, 50 Timothy hay, 133 — soiling, 118 Tongue, 37 Tonic feeds, 168. Total digestible nutrients, 49, 50 True protein, 34 Trvpsin, 43 Trypsinogen, 43 Tryptophane, 62 Turnips, 55, 124 U Underfeeding, influence on produc- tion, 64 Use of home-grown feeds, 246 Variety in the ration, 56, 62, 92 Venous blood, 44 Vetches for soiling, 114 Villi, 44 Vitamines, 34, 54, 55, 56, 93 — , anti-neuritic, 53 — , anti-scorbutic, 56 — , functions of, 54, 55, 56 — in corn, 137 — , influence on production, 63 — , milk free from, 54 — , necessity for calves, 54 W Water, 26, 31, 32, 52 — , abundance of, 234 — for all stock, 233 calves, 224, 233 cows, 233 — , functions of, 52 — , influence on production, 60 — in milk, 233 — , methods of furnishing, 234 — , purity of, 234 — soluble B, 34 , functions of, 55 INDEX 281 Walcr-soluble B, sources of, 55 — soluble C, 34 , functions of, 56 ; sources of, 56 — , source of, 234 Waxes, s$ Whale meal, 164 Wheat, 34, 143, 144 — bran, 89, 144 , phytin in, 144 — , flour wheat middlings, 145 — middlings, 144 — , Red Dog flour, 145 — shorts, 144 — , standard middUngs, 144 — straw, 133 — soiling, 116 WTiey, 162 Whey for calves, 216 White corn, 55, 137 Whole milk insufficient for calves, 221 Whole oats, 143 Winter milk production, ig6 — rations, iq8 Xanthophylls, 35, 56 Xerophthalmia, 55 Yellow corn, ^Sr ^37 Yield of milk, influence on balance of nutrients, 85 Zein, 137