ilk - m I .$■-■,: «i 1 W0 l#f CHICHBHS C. R. Grau, F. H. Kratzer, and W. E. Newlon ■MMMnMHHRHH -• * K ■s .," v ■■> UiiAiiilAA JL# %JI, . / . -, ,- .. S-myb\**m. **>■ ^^r California Agricultural Extension Service The College of Agriculture University of California, Berkeley CIRCULAR 159 DECEMBER 1949 *PW What Is the Best and Most Practical Way to Provide a Balanced Diet for Chickens? This is the big question for the poultryman who wants to maintain • High livability • Good hatchability • Rapid, efficient growth of meat birds WITH • Efficient egg production • Low operating costs This Circular gives you the answer. It is a guide to chicken nutrition. The poultryman who reads it carefully will be pre- pared to get the best results in buying or mixing his own feeds— to provide a diet that meets all essential nutrient re- quirements for his birds. Food for Chlck©nS gives you latest facts about — 1 .The Nutrients — functions, deficiency symptoms, recom- mended allowances • Energy sources • Minerals • Proteins • Water • Vitamins 2. Feed stuffs as Sources of Nutrients • Cereals and other energy sources • Vitamin sources • Protein concentrates • Green feeds • Mineral sources • Harmful components 3. Basic Feed Formulas for Efficient Production • Chick-starting mashes • Breeding mashes • Broiler-fryer mashes • All-purpose mashes • Laying mashes This circular supersedes Extension Circular 108. The Authors: C. R. Grau and F. H. Kratzer are Assistant Professors of Poultry Husbandry and Assistant Poultry Husbandmen in the Experiment Station; W. E. Newlon is Extension Specialist in Poultry. ftt» FOR CHIC KINS Feed costs amount to more than half the total costs of poultry production. This fact obliges the poultryman to give care- ful consideration to the problems of poul- try feeding. High livability, rapid and efficient growth of meat birds, efficient production of eggs, and good hatchability can be obtained only when feeds of high quality are used. At the same time it should be kept in mind that good manage- ment and breeding practices are just as important as good nutrition. A good feed cannot alone produce good results. The problem is to provide a feed that is adequate nutritionally, yet is cheap enough to allow a satis- factory profit. An adequate feed con- tains all necessary nutrients, properly balanced and in readily available form, and a minimum of harmful substances. The nutrients which must be present in the diet are classified as energy sources, proteins, minerals, and vitamins. These are found in plants and animals, which provide the feeds and foods for domestic animals and man. Some nutri- ents are produced by microorganisms in the digestive tract. In ruminants, particu- larly, important nutrients such as amino acids and vitamins are manufactured by bacteria, yeasts, and protozoa from simple sources of nitrogen and energy. In swine and poultry, microorganisms apparently play a comparatively small part in meeting the needs for these nutri- ents. The feed must contain most of the nutrients required by these ani- mals. we NumcNTs ENERGY SOURCES The energy the chicken needs to move — to eat, digest, and utilize feed — to maintain a normal body temperature — is derived from en- ergy sources in the diet: carbohy- drates, fats, and proteins. The chicken, like other animals, needs energy as well as other nutrients to carry on its life processes. Carbohydrates and fats are useful to the animal primarily as energy sources; proteins also furnish energy, but they are most important as structural components of the animal body. Carbohydrates Carbohydrates, the most important energy sources for chickens, are complex organic compounds of carbon, hydrogen, and oxygen that are manufactured by plants from water and carbon dioxide in the presence of sunlight. The various sugars, such as glucose (dextrose) and sucrose (cane or beet sugar), are well known examples of carbohydrates. Green plants combine thousands of the glucose molecules to form the large starch mole- cules, which are then stored in plant cells. When the animal eats starch, the large, insoluble molecules must be broken down into glucose. This process, digestion, is brought about by the action of digestive enzymes, which are proteins, and which are secreted into the intestinal tract of the animal. The action of these enzymes is to split starch into glucose, which can then be absorbed into the blood stream through the intestinal wall and distributed to all parts of the body. [3 Some carbohydrates (like cellulose) are almost indigestible. If the diet con- tains very large amounts of these mate- rials, the chicken is unable to eat enough feed to provide its needed energy. Fats Fats have more than twice the energy value of carbohydrates, but primarily be- cause they are important in man's diet, they are too expensive to be used as en- ergy sources for chickens. The animal can readily manufacture fat from carbohy- drates and proteins. The energy stored in body tissues is mostly in the form of fat. Fats are composed of fatty acids, such as stearic or oleic acids, attached chemi- cally to glycerol (glycerin). Fats cannot be used satisfactorily in large amounts in feeds because they may become rancid, and rancid fats destroy certain vitamins needed by the animal, and may also produce a disagreeable flavor in both eggs and meat. PROTEINS To manufacture and maintain the tissues of the body, the chicken needs certain kinds and amounts of amino acids. These are obtained from proteins in the diet. The active tissues of living organisms are largely proteins. Animal and plant cells manufacture these complex sub- stances by combining the comparatively simple amino acids in various ways. Examples of animal materials containing large amounts of protein are muscle, blood, and feathers. Feed proteins are first broken down into their amino acids in the chicken's digestive tract. These are then absorbed into the blood stream and carried to vari- ous parts of the body, where they are used to build new tissues, to repair old or damaged tissues, and to make enzymes and special materials such as eggs. An important problem is to supply the amino acids in the most economical way. Nineteen amino acids are commonly present in plant and animal proteins, but the amounts of each vary a great deal in different feedstuff proteins. The tissue proteins which the animal manufactures, however, have an essentially uniform amino acid composition; so that if the animal's diet lacks a particular amino acid, the animal must manufacture it from other constituents in the diet if it is to form tissue. The chick has the ability to manufacture nine of the 19 amino acids. The remaining ten must be provided in the feed if weight loss is to be prevented. The feed must also provide some of the nine amino acids, especially glycine, which the chick cannot manufacture fast enough for efficient growth, and cystine and tyrosine, which are made from methi- onine and phenylalanine (see footnote, Table 1). The amounts of amino acids required in the chick's diet are given in Table 1. Because the proteins of feed- stuffs provide adequate amounts of most of the amino acids, only the five listed at the top of the table need be considered. Analyzing Feeds for Protein Proteins and their amino acids contain nitrogen in their molecules. This provides a basis for estimating the amount of pro- tein in feeds. The average nitrogen con- tent of pure proteins is about 16 per cent; hence if a feed contains 8 per cent nitro- gen by analysis, it is said to contain 50 per cent "crude protein." The usual method of analyzing feedstuffs for pro- tein is to determine their content of nitro- gen, express it in per cent, and multiply this percentage by , or 6.25 (see Table 16 4, page 17) . Growth The bird needs not only the minimum amounts of the amino acids listed in Table 1, but also additional amounts of these or other amino acids to serve as raw materials for tissue formation. It has been 4] found that for satisfactory growth the young chick needs about 20 per cent pro- tein in its diet. This is the total require- ment, including the essential amino acids. As the bird grows, its protein requirement gradually declines, reaching a level of about 15 per cent at maturity. Digestibility Some proteins (such as hair and feath- ers) are not digested (broken down) by the enzymes of the alimentary canal, and the animal cannot make use of amino acids from these sources. In general, in- gredients of poultry feeds are highly digestible; but digestibility is not always a guarantee of nutritional value. Recent investigations have shown that some feeds formerly thought to be poorly digested because they did not promote rapid growth are actually highly digestible, but deficient in one or more essential amino acids. Egg Production The amounts of amino acids which the hen requires to maintain a high level of egg production have not yet been deter- mined. But it is known that marked deficiencies of lysine, tryptophane, methi- onine, or isoleucine stop egg production and cause loss of body weight. Partial amino acid deficiencies result in de- creased egg weight. Deficiency Symptoms Unfortunately there are no symptoms exclusive to amino acid deficiencies. The usual deficiency symptoms are similar to the symptoms of starvation: weakness, lack of appetite, poor growth and poor feathering. Poor appetite is the outstand- ing symptom of amino acid deficiencies, but it should be remembered that appetite is adversely affected by a deficiency of almost any essential nutrient. VITAMINS are present in small amounts in plant and animal materials. All ani- TABLE 1 — The amino acid require- ments for chick growth, expressed as percentages of the diet. Amino acid Per cent of diet Arginine 1.0 May be deficient Lysine 0.9 in mixtures of Methionine 0.5 natural feed- *Cystine 0.3 stuff s. Tryptophane. . 0.2 Glycine 1.0 Histidine 0.2 Isoleucine 0.5 Leucine 1.4 Not likely to be Phenylalanine 0.7 deficient in prac- * Tyrosine 0.7 tical rations. Threonine. . . 0.45 Valine 0.7 Total 8.55 ♦Cystine and tyrosine — both constituents of tissue proteins — are also included above, although they are not strictly dietary essentials. The chick's body can convert methionine to cystine and phenylalanine to tyrosine, so that cystine and tyrosine need not be in the feed if enough methionine and phenylala- nine are present. In practical rations, though, we are concerned with cystine levels because virtually no feeds contain enough methionine to supply both methionine and cystine. mals need vitamins — for normal growth, maintenance, and repro- duction. Chickens need most of the vitamins required by other species, and are very exacting in their vita- min needs. Vitamins and vital processes: The functions of the vitamins in the body are gradually being learned. Some of the vi- tamins are known to be necessary for the release and use of energy from carbohy- drates, and one (vitamin D) is concerned primarily with the utilization of calcium and phosphorus. A deficiency of a vita- min may interfere with a vital process, so that the animal may die. Some vitamin deficiencies produce specific effects, such as paralysis or dermatitis; but the most general result of vitamin deficiencies is [5] Figure 1— Above: Inflammation of the eye re- sulting from an acute deficiency of vitamin A. Compare with normal bird below. poor growth. An exception is vitamin K deficiency, which causes hemorrhages but does not affect growth. The vitamins are conveniently divided into two groups : ( 1 ) fat-soluble vitamins, and (2) water-soluble vitamins. Fat-Soluble Vitamins Vitamin A: Vitamin A occurs only in animal tissues, but plants contain the closely related compound carotene, which the animal can convert into vita- min A. Beach and Stewart, in their Dis- eases of Chickens (1942), remark that a severe deficiency of vitamin A or carotene in the ration results in "decrease in appe- tite; weakness and emaciation; droopi- ness; reddened and watery eyes (Figure 1 ) , which may be followed by the forma- tion of an adherent white film over the third eyelid and a mass of white cheesy material within the eyelids ; the formation of yellowish- white, round, cheesy, pustule- like patches about the size of a pinhead in the mouth and throat; and occasionally the formation of masses of white, cheesy material in the cleft or elsewhere in the mouth. "Post mortem examination of birds usually shows the kidneys to be very pale and marked with a network of very fine white lines. Occasionally a deposit of a white material is also found on the surface of the liver, on the membrane around the heart, or elsewhere on the surface of the organs." A mild deficiency results in poor growth, low egg production and reduced hatchability. In chronic cases of vitamin A deficiency, birds show generally inco- ordinated movements and a jerky, stag- gering gait. Requirements: The vitamin A require- ment of mature birds is considerably higher than that of young chicks. The minimum requirement for chicks is about 1200 International Units (I.U.)* per pound of feed, while laying hens need at least 2000 I.U. per pound. Since the amount required for good egg production is also adequate for good hatchability and chick livability, it is unnecessary to in- clude more vitamin A in a breeding ration than in a laying ration. Sources: The usual sources of vitamin A activity in poultry rations are alfalfa meal, yellow corn, feeding oils, or dry vitamin A concentrates. Fresh greens when available are valuable as a source of carotene (and of other nutrients too) . Vitamin A and carotene are easily de- stroyed by heat, by exposure to sunlight, and by contact with air, minerals, or rancid oils. Therefore feeding oils should always be stored in closed containers, in a cool dark place, and alfalfa meal should be kept out of sunlight, in a cool place. Because the conditions of alfalfa meal * The International Unit is identical to the unit of the United States Pharmacopoeia (U.S.P. unit). [6 production and storage vary widely, dif- ferent samples differ markedly in carotene content. Generally, the content is lowest in the early spring. The carotene content of alfalfa meal cannot be estimated accu- rately from the color of the meal. It is advisable to buy and use alfalfa meal on the basis of the carotene analysis of each sample. The carotene content of alfalfa meal is often expressed in milligrams per 100 grams of meal; a meal containing 10 milligrams carotene per 100 grams has a vitamin A activity of 75,700 I.U. per pound. Vitamin D: Animals need vitamin D for the proper utilization of calcium and phosphorus. A deficiency of vitamin D in chick rations results in rickets, which is characterized by poor growth, lameness, swelling of the hock and rib joints, and crooked breastbones (Figure 2). The bones are poorly calcified and easily bent. In adult birds, the leg bones become brit- tle. Egg production is low; many of the eggs are thin-shelled; and hatchability is poor. Of the several forms of vitamin D that have been identified, some are active for the rat and other mammals, but have a very low activity for poultry. For this reason it is important that vitamin D sources for poultry be of guaranteed po- tency in Association of Official Agricul- tural Chemists (A.O.A.C.) chick units, which are measures of the form called vitamin D 3 . Sources: Ultraviolet light, a sunlight component, changes some of the sterols present in the body into vitamin D 3 and can completely fill the bird's requirement for vitamin D. However, not all birds are exposed to direct sunlight, and atmos- pheric conditions such as clouds, fog, and Figure 2— The bird on the right received a diet deficient in vitamin D and was not allowed access to sunlight. Note the poor growth and crooked keel. Other causes of crooked keel are roosting on narrow roosts and mineral deficiency or imbalance. [7] smoke reduce the amount of ultraviolet light. Very little ultraviolet light passes through ordinary window glass. It is therefore a good practice to supply in the ration all the needed vitamin D. Feeding oils or dry products containing synthetic vitamin D are supplements com- monly used in poultry rations. Vitamin D is usually more stable than vitamin A, but its stability is affected by many of the conditions affecting vitamin A. Concen- trates of vitamin D should not be pre- mixed with mineral or granular materials such as dried milk products, because such premixing may, for some unknown rea- son, destroy the vitamin. Requirements: In the absence of sun- light, growing chicks need at least 90 A.O.A.C. units of vitamin D 3 per pound of feed, while laying hens require 180 units per pound. Vitamin E (known also as alpha toco- pherol) : The most common symptoms of a deficiency of vitamin E are incobrdi- nated movements of the legs, wings, and neck, sometimes followed by convulsions. A similar condition which was observed in the field and had been referred to as "crazy-chick disease" is now regarded as a result of vitamin E deficiency. There is also an abnormal movement of fluid into the brain and other tissues, and the skin may have a reddish appearance. The symptoms of vitamin E deficiency must not be confused with the paralysis symp- toms of "fowl paralysis" (neurolympho- matosis) , which is not related to vitamin E deficiency. Requirements and sources: Chicks re- quire approximately 1.35 milligrams of alpha tocopherol (vitamin E) per pound of feed. The requirement for adult birds has not been determined. The vitamin is present in the cereal components of poul- try rations, and in dehydrated alfalfa meal, liver meal, and fresh greens, so that our usual poultry rations are not likely to be lacking in this factor. Vitamin E like vitamin A is rapidly destroyed by rancid fats; it is essential that no ingredients containing rancid fats be included in the poultry ration. Vitamin K: This vitamin was dis- covered when it was observed that birds maintained on a special ration bled se- verely after being wing-banded. The ina- bility of the blood to clot was found to be a result of a dietary deficiency of an es- sential substance, which was later iden- tified as vitamin K. Growing chicks require about 0.18 milligram of vitamin K per pound of feed, and mature birds need at least 1.0 milligram per pound. Since alfalfa is a rich source of vitamin K, practical rations which contain as little as one per cent of alfalfa meal contain adequate amounts of this vitamin. Water-Soluble Vitamins Riboflavin: Riboflavin (formerly called vitamin G, or vitamin B 2 ) is re- quired by chicks for normal growth and for the prevention of a condition known as curled-toe paralysis, which develops when chicks are fed a ration slightly de- ficient in riboflavin. The birds walk on their hocks, with their legs extended stiffly in front of them and the toes curled inward (Figure 3). The sciatic nerves show a typical enlargement. In mature birds, lack of riboflavin means lowered egg production and a se- rious reduction in hatchability. Develop- ing embryos, in eggs from hens fed riboflavin-deficient diets, show "clubbed down," edema (abnormal amount of fluid in tissues), and other abnormalities. Among such embryos there is a high death rate during the middle part of the incubation period. Further, the chicks which do hatch are less likely to survive than chicks hatched from eggs containing adequate amounts of riboflavin. Sources and Requirements: The cereals are generally poor sources of riboflavin: other sources of the vitamin must be added to the ration to insure an adequate supply. Milk products, liver meal, alfalfa [8 Requirements: The chick requirement for pantothenic acid is about 4 milligrams per pound of feed, while laying hens need 0.7 milligram and breeding hens 3.6 milli- grams. Sources: Among the good natural sources of pantothenic acid are liver meal, condensed fish solubles, molasses, milk products, alfalfa meal, and peanut meal. If riboflavin is supplied by natural feedstuffs, the ration is not likely to be deficient in pantothenic acid, since feeds rich in riboflavin are usually rich in pantothenic acid. A form of dermatitis which is some- times observed under field conditions re- Figure 3— A dietary deficiency of riboflavin sembles the dermatitis of pantothenic acid causes curled-toe paralysis. The chick rests on deficiency, but has not been shown to be its hocks, with its toes curled inward. me res ult of a specific nutritional dcfi- meal, and various fermentation products are among the rich natural sources. Syn- thetic riboflavin is also widely used. The requirement for chicks is about 1.35 milli- grams per pound of feed; for laying hens, 0.7 milligram; and for breeding hens, 1.1 milligrams. Although riboflavin is destroyed by di- rect sunlight, it is relatively stable in mixed feeds. Exposure of feed to direct sunlight for several days results in only slight losses of riboflavin. Pantothenic Acid: Chicks fed rations deficient in pantothenic acid grow slowly and develop dermatitis. The dermatitis starts with the appearance of incrusta- tions at the corners of the beak and on the eyelids. As the condition becomes more severe the eyes become stuck shut (Figure 4), and the body and feet may bear scabby lesions. The feathers become very brittle. Hens need pantothenic acid for egg production and good hatchabil- ity. However, the embryos of eggs from hens fed diets deficient in pantothenic acid (unlike those from hens given ribo- flavin-deficient diets) show no character- istic deformities. Figure 4— Early and late stages of dermatitis caused by pantothenic acid deficiency. Note the incrustations at the corners of the mouth, the first symptom. [9] ciency. No cause for this field condition is yet known. Animal protein factor (probably the same as the cow manure factor and vita- min B 12 ) : It has long been known that rations containing some animal protein concentrates promote better growth of chicks and better hatchability than straight vegetable rations. It is now ap- parent that the special benefit of animal products is due largely to the activity of this factor, which appears to be a vita- min. A deficiency of the factor reduces growth and hatchability. Sources and Requirements. Rich sources of the vitamin are fish meal, fish solu- bles, liver meal, skim milk, and butter- milk. Some samples of meat scraps and certain fermentation products have also been found to contain the vitamin. Starting rations and breeding rations should contain 3 per cent to 5 per cent animal protein concentrates, or fermen- tation products which furnish equivalent amounts of the vitamin. Choline: Chicks require choline for normal growth and for the prevention of perosis (slipped tendon) . Perosis is char- acterized by the swelling of the hock joint, rotation of the shank outward, and in severe cases by the slipping of the tendon from the bones at the hock joint (Figure 5). Either or both legs may be affected. Birds suffering from this con- dition may have difficulty in obtaining enough feed and water, and may be trampled by their penmates. Perosis may also be caused by a deficiency of manga- nese, biotin, nicotinic acid, or folic acid. Where wire floors are used, perosis may be more frequent than where litter is used. Birds of the heavy breeds, more- over, seem to be more susceptible to perosis than birds of the light breeds. Requirements: Adult birds have the abil- ity to form choline in their bodies, so the choline content of their rations need not be considered. Chicks require a minimum of 0.1 per cent choline in the ration. Liver [10 meal, fish meal, and some oil meals are good sources of choline (see Table 6) . The chick not only needs choline for the prevention of perosis, it also requires choline, or methionine or betaine for the manufacture of important tissue constitu- ents. Rations which depend upon soybean meal as the protein concentrate are more likely to need supplements of choline (or methionine or betaine) than rations con- taining fish and meat products or sesame seed and sunflower seed oil meals. We cannot yet state exactly what amounts of choline, methionine, or betaine should be added to a particular ration in order to produce the best growth. Recent studies indicate that an inter- relationship exists between choline and the animal protein factor. A diet well sup- plied with animal protein factor requires less choline than one poorly supplied. The Following Water-Soluble Vitamins Are Not Likely to Be Deficient in Practical Rations: Thiamin: Thiamin, or vitamin B 1? is required by chicks for normal growth and for the prevention of nervous disorders. Chicks need approximately 0.9 milligram per pound of feed. The amount needed by adult birds is unknown, but probably does not exceed chick requirements. Since the cereals and their by-products contain large amounts of thiamin, practical poul- try rations provide ample amounts of this vitamin. Pyridoxine (Vitamin B 6 ): The lack of pyridoxine in chick rations retards growth and gives rise to convulsions and other nervous symptoms. Breeding hens require pyridoxine for good hatchability. The vitamin is relatively stable in feed- stuffs, and there is no indication that prac- tical rations are deficient in it. Nicotinic Acid (Niacin): Nicotinic acid, one of the B-complex vitamins, is required in relatively large amounts for normal chick growth. Practical poultry Figure 5— Stages in the onset of perosis, or slipped tendon. Bird above is normal. Bird at upper right is in the initial stage. Center and lower, advanced perosis. «* ■ ■■■■ rations are not likely to be deficient, since barley, wheat and wheat by-products, alfalfa meal, liver meal, fish meal and meat scraps are good sources of nicotinic acid. The principal danger of a nicotinic acid deficiency occurs when corn is fed in large amounts; corn is particularly low in nicotinic acid. Corn is also low in tryp- tophane, which the chick can use for the manufacture of nicotinic acid. Nicotinic acid deficiency is one of the many causes of perosis (see choline above) . The chick requirement for growth is approximately 7 milligrams per pound. Biotin: Biotin is needed by the chick for normal growth and the prevention of perosis and dermatitis. The dermatitis caused by a biotin deficiency is different from the dermatitis of pantothenic acid deficiency. Its first symptom is a thicken- ing of the skin on the bottoms of the feet, followed by a cracking of the skin. Later, as the condition becomes more severe, the corners of the mouth, the eyes, and the body skin may be involved. Breeding hens need biotin for good hatchability ; low hatchability and mal- formed embryos result when the ration contains inadequate amounts of biotin. The chick needs about 0.04 milligram of biotin per pound of feed. Since corn, barley, soybean oil meal, and alfalfa meal all contain more than this amount per pound, a deficiency of biotin in poultry feeds is very unlikely. However, feeding raw egg white causes the biotin in the ra- tion to become unavailable to the bird. Egg white should always be cooked to make biotin available, and also to prevent the spread of pullorum disease. Folic Acid (Pteroylglutamic Acid): This vitamin is required by chicks for normal growth and for the prevention of anemia. Folic acid deficiency also causes poor feathering and poor hatchability. Approximately 0.2 milligram of folic acid per pound of feed is required by chicks; however, the requirement has been found to differ among different strains. Alfalfa meal, soybean oil meal, and liver meal are good folic acid sources. Because practical rations generally cover folic acid requirements, no special con- sideration need be given to this vitamin. Ascorbic Acid (Vitamin C): Ascorbic acid is needed by the tissues, but birds have the ability to make sufficient amounts of it. It is therefore unnecessary to supply additional ascorbic acid to the ration. MINERALS All birds need a continuous supply of minerals — to form new bone and soft tissue in the growing bird — to replace minerals lost by excretion — to form eggs, and for other vital functions. Common poultry feed- stuffs may not supply all mineral requirements. The minerals known to be required by chickens are calcium, phosphorus, sodium and chlorine (combined as sodium chlor- ide, common salt), magnesium, manga- nese, potassium, iron, copper, and iodine. Sulfur must be provided by the amino acids methionine and cystine. Cobalt and zinc, though needed by some other ani- mals, have not yet been shown to be needed by chickens. The requirements for minerals which common poultry feedstuffs may not ade- quately supply are given in Table 3. Calcium and Phosphorus Calcium and phosphorus, the most im- portant constituents of bone, are required in large amounts by the growing bird. The laying hen also needs large amounts of calcium for the manufacture of egg shells. Both calcium and phosphorus are needed for the normal functioning of many tissues besides bone. For the efficient utilization of cal- cium and phosphorus, the animal requires an adequate amount of vi- tamin D. A deficiency of vitamin D increases the calcium and phosphorus re^ [12] quirements. Also, the ratio of calcium to phosphorus in the diet affects the vitamin D requirement: when the ratio of cal- cium to phosphorus deviates very far from two to one, more vitamin D is needed to maintain the efficient use of these minerals. Some of the phosphorus found in plant cells is not readily available to the chicken; good diets contain some inor- ganic phosphorus source. A lack of calcium, phosphorus, or vi- tamin D results in poor growth and poor calcification (mineralization) of the bones— the nutritional disease condition called rickets. Sodium Chloride (Salt) The requirement for salt is not more than 0.5 per cent of the diet. Very low levels may result in poor growth; very high levels may be poisonous. Manganese Manganese deficiency in chick rations results in perosis, a disease of the hock joint (see choline above), and in abnor- mally short and poorly mineralized bones. In laying hens, a manganese deficiency results in poor production, thin egg shells, low hatchability, and embryo deformities. An excess of calcium or phosphorus raises the manganese requirement. Many feed- stuffs do not contain enough manganese to meet the bird's needs ; supplements of manganese salts are therefore addsd to most poultry rations. Magnesium Magnesium deficiency results in poor growth and in convulsions (caused by a breakdown of certain brain cells). Al- though the chicken's magnesium require- ment is high (180 milligrams per pound) , practical rations always supply the needed amount. On the other hand, feeding exces- sive amounts of magnesium results in poor growth, poor calcification of the bones, and production of thin-shelled eggs. Iron and Copper Iron is required for red blood cell for- mation; copper aids in iron utilization. Poultry feedstuffs ordinarily contain more than enough of both minerals to satisfy the chicken's needs. Potassium The diet of the chick should contain about 0.3 per cent potassium to promote best growth. Since vegetable materials contain relatively large amounts of potas- sium, a deficiency in practical rations is unlikely. Iodine The animal needs iodine for the manu- facture of thyroxine (the thyroid hor- mone) . In addition, some feedstuffs, such as soybean oil meal, contain substances which cause goiter (enlargement of the thyroid gland) ; iodine— in the form of potassium iodide— is necessary in the diet to prevent this condition. Poultry of all ages require about 0.5 milligram of iodine per pound of feed. When marine products (for example, fish meal or shell flour) are included in the ration, supple- mentary iodine is not usually needed. But when high levels of soybean oil meal are fed, it is desirable to use iodized salt in the ration. WATER Water is not usually regarded as a nutri- ent, but it is essential for all poultry. Birds in fact can live longer without feed than without water. Clean water should be kept before the birds at all times. DIAGNOSING NUTRITIONAL DEFICIENCIES It is usually difficult to diagnose nutri- tional deficiencies under field conditions because infectious diseases so often com- plicate the picture. For this reason we urge the poultryman to take advantage of the free diagnostic service offered by the state and county pathological laborato- [13] E o *• o. E I CM a o cs 2 « «« 03 CO $ CO ■3 I i fl . ed w .s •°3 eg Pi sg CD »o bo Sg o g IS CO -u T» O m © ° ^3 «a co co fo B o -g *n tt i*§ .2 §"SS.S« w co ■is a I fl ^ p* w-3 bo - ^4- O-H g£ t5pH«|o « H C0« ed r „ CO ^ O ta,^ CO £ p cd Oi.Sxj m3o I* O Q. CO CO M M CO CO CO CO * is lO lO bo ea <3 eS a CO CO Co ** CO . co c X co J* 88 CO co pj £* ►J CO o a CO o CO Q. 5 b « e « S ,2 o O «-i CO CO CO g. M M« ■Sa O J2 g CO CO ^ o O co BS o| CO* m Cm . CO . CO gflfl O CO cd O > Jh ■ ~ ^ CO co CO co 52 bo — . cj bp I -I Crt M co j3 02 s >» co CO CO o CO Cd o. o . "O co a >» CO CO ~ o ^ cd s'S co 2 so JS ^J CO *"• s& o cd co "I bo £ O R f-i CO eaa bo-^ •S3 bo co N J3 ctl n +3 cd CO ■B °~ xi a O CO c3 > O •O cd cd p- co c» CO co ^! co 2 ««^ ft cd «.2 S^ 3 a *-2 a g •S-s o 3 a 2 So x+° o + + + 0) a 5 H i l # < ^ . s ^ '3>^ Si* 888 o o co o o 2% o 8 3 1 - 5- ■s C N N CO CD CO CO £*„ "SI 2 # w £ w >^° O CO IE w k till If " io to io io io lis? IS** «n O fl-fl t»» O ., ° -F< » w u e fl p. ic to m 6 © © O lO q m ." « ti M S 5R S 03 CO 9) «i P5"' 3 a s "5 #■ i 2°" to fl «5 ° a ° oo oo oo O 00 q e .2 do© r-i d T-l ■fa ; o >, o D ^U-°JS z 1 in as «! o ft (D (O O H ri W o q o e4 fl 5T3 •— *S ^ M P.^ O IH « — -i 03 ^ w "5— fl « ca^.g 2 © fl fl lis O CD lO O IO o §** fl e Com ^: lO T3 CD CD •§fl?iS 22 CD CD O Pi «3 o .2 O e c i ^.j a p tf-Sfl.S? '■S -3 p •£ « : »-3 M *i-z .4 a a Isis bo bo CD £ '■31 1 Sill ) » » a 1 § ( : i cfl ries. Details of the services available will gladly be given by your county farm advisor. If it is impossible to obtain laboratory diagnosis, the information summarized in Table 2 may be helpful in recognizing certain nutritional deficiencies. Some symptoms, such as curled-toe paralysis, are quite specific results of a nutritional deficiency. Others, such as dermatitis, gizzard erosion, and cannibalism, are not related exclusively to malnutrition. For this reason, laboratory verification of the suspected deficiency is most desirable. RECOMMENDED NUTRIENT ALLOWANCES In formulating rations, the poultryman should first calculate the amounts of the various nutrients which the chicken will actually derive from the feed, and then compare them with the bird's require- ments. The stability of the various nu- trients—under different conditions of grinding, mixing, storing, and feeding- is an important consideration. Of the va- rious nutrients, vitamin A, carotene, and vitamin E are the least stable, while the mineral elements are the most stable. The nutrient allowances given in Table 3 take account of variations in stability of the nutrients; but if these allowances are to hold good, feedstuffs should be stored for the shortest time consistent with economy of purchase, and should if possible be kept in dark, cool, dry places. If these precautions are taken, a given feed which meets the calculated allowances should prove adequate in practical use. Note : The allowances given in Table 3 are not all equally accurate. For example, the choline and pantothenic acid allow- ances for chick-starting rations may be unnecessarily high. This excess is a mar- gin of safety. We are not yet sure of the exact content and availability of these and other vitamins in feedstuffs. [15] mdSIUffS AS SOQRCiS OF HOTRtiNTS Up to this point we have considered the nutrients as well-defined groups of sub- stances in order to explain their func- tions. In practical feeding, however, we are not ordinarily concerned with sep- arate nutrients, but with mixtures of nu- trients as they occur in feedstuff's. This section gives information on the nutri- tional value of different feedstuffs for poultry. To insure maximum uniformity and to protect the industry, the California State Department of Agriculture, Bureau of Field Crops, has defined the various feed- stuffs in terms of raw materials used, methods of processing, and chemical analysis. These definitions have been pub- lished in "Commercial Feeding Stuffs Regulations"— copies are obtainable from the Bureau of Field Crops— and are essen- tially the same definitions as those adopted by the Association of American Feed Con- trol Officials. They make possible the en- forcement of laws designed to protect both feed mixers and users. The amounts of the various nutrients contained in feedstuffs are presented in Tables 4, 5, and 6. Feedstuffs may be grouped conveni- ently into energy, protein, vitamin, and mineral sources, although there is some overlapping between these groups. The cereals and cereal by-products, for example, are primarily carbohydrate (en- ergy) sources, but they furnish appreci- able amounts of protein, many vitamins (especially thiamin and vitamin E), and minerals (particularly potassium, mag- nesium, and iron). ENERGY SOURCES Cereals and Cereal By-Products Barley is the most common feed grain in California. When its price is compara- tively low, it may well be fed as the prin- cipal grain. Birds raised on other grains may not consume whole barley readily, but birds trained to eat it early enough will consume it freely. In experiments carried out at this Sta- tion over a four-year period, it has been found that chicks fed barley grow some- what more slowly than those fed yellow corn. Birds raised on rations containing barley as the principal grain and fed these rations during the laying period, however, were found to have a lower re- productive mortality rate than those simi- larly fed yellow corn rations. The feeding value of different grades of barley is roughly proportional to the weight per bushel. Generally, the heavier the barley the higher is its feeding value. Light-weight barley should not be used unless it can be bought at correspondingly lower prices than the heavier barley. Barley screenings and hulls should never be used as poultry feeds. Corn: This valuable grain for poultry may be used when available at a fair price in comparison with other grains. Corn is especially valuable in meat-bird rations, which must promote rapid growth. Yellow corn is more desirable than white corn, because it contains a yellow pigment (cryptoxanthin) which has some vitamin A activity. Yellow corn is not a rich source of vitamin A activity, but it will contribute significant amounts to the ration when high levels are fed. Yellow corn also provides a yellow pig- ment (xanthophyll) for egg yolks and for the skin and shanks of birds that normally have yellow skins. Argentine flint corn has the same feeding value for poultry as domestic corn, but it contains more of the skin- and yolk-coloring pigments. Milo: For this feedstuff see Sorghum grains, page 18. [16] TABLE 4 — Average proximate composition of feedstuff s used for poultry. Feedstuff Alfalfa leaf meal Alfalfa meal Alfalfa, fresh Babassu oil cake meal Barley Beans, cull lima Blood meal Bone meal, raw Bone meal, special steamed Brewers' dried grains Buttermilk, condensed Buttermilk, dried Coconut meal Corn Corn germ meal Corn gluten feed Corn gluten meal Corn oil meal Cottonseed meal (40% protein) Distillers' grains with solubles Fish meal Fish solubles, condensed (50% solids) Linseed oil meal Liver meal Meat scraps Meat and bone scraps Milk, dried skim Milo Molasses, cane Oats, Pacific Coast Peanut oil meal Potatoes, dried Rice bran oil cake meal Rice millrun bran Safflower seed oil meal Screenings oil feed Sesame seed oil meal Soybean oil meal Sunflower seeds Sunflower seed oil meal Wheat Wheat bran Wheat middlings Wheat millrun Wheat shorts Whey, condensed Whey, dried Yeast, pure dried Yeast culture Crude protein per cent 20.3 16.6 4.7 23.9 9.7 22.3 81.6 24.6 7.5 26.2 10.9 32.9 20.5 9.9 14.3 24.8 45.0 23.2 40.6 29. 66.3 33.5 30.9 67.9 60.1 50.6 34.8 9.6 3.6 9.8 45.9 10.4 16.0 11.7 17.4 33.7 41.8 44.0 16.1 49.2 10.8 15.6 14.8 15.6 15.8 6.3 12.5 47.1 13.7 Crude fat Crude fiber per cent per cen 3.2 17.9 2.6 25.6 0.8 8.0 6.9 12.0 2.3 6.2 1.1 4.6 0.9 0.6 5.6 0.6 0.7 0.6 6.6 14.7 1.9 0. 5.9 0. 7.8 10.4 4.2 2.1 6.0 5.1 2.8 7.4 2.1 4.1 5.5 10.4 6.6 11.3 9. 7. 7.7 0.5 4. 0. 6.1 9.5 15.4 1.4 10.0 2.2 9.7 1.8 1.2 0. 3.0 2.0 0. 0. 5.4 10.5 7.0 6.1 0.3 2.0 8.2 9.2 15.7 9.5 2.8 40.0 7.6 10.2 9.9 6.1 5.4 5.6 24.7 27.9 1.6 10.4 2.1 2.7 4.0 8.5 3.5 3.0 4.1 7.7 4.5 5.8 0. 0. 0. 0. 1.9 4.6 4.5 3.8 Ash per cent 10.2 8.8 2.3 5.7 2.7 6.0 5.1 58.8 80.5 4.0 2.2 7.9 6.8 1.5 4.2 6.1 2.6 2.4 6.5 4. 15.6 8.9 5.5 5.4 20.9 29.9 7.6 1.9 9.8 3.6 5.2 4.3 13.4 9.8 2.5 5.8 12.1 5.5 3.1 6.9 1.8 5.4 2.4 4.7 3.8 4.8 10.4 6.8 3.6 * From data obtained by Feed Control Laboratory, Bureau of Field Crops, California Department of Agri- culture. [17] Oats are a good poultry feed, though even heavy oats have a comparatively high fiber content because of the hulls. This grain offers no advantages over other grains such as barley, but it may be used satisfactorily when its price is consistent with its feeding value. Rice is low in protein but high in di- gestible energy (see next column). The superior grades of rice are too costly for use in poultry rations, but cracked and shrunken grains can sometimes be ob- tained at reasonable prices. Rice by-products: Fresh rice bran and rice polish are nutritionally valuable, palatable feedstuffs. But since their fat content is high they should not constitute more than ten per cent of the mash. Also, they become rancid soon after milling, and should not be stored very long. Prop- erly used, rice by-products give satisfac- tory results in poultry rations. Recently a defatted rice bran product- rice bran oil cake meal— has become avail- able for poultry feeding. This product does not become rancid during storage, and feeding trials have shown it to be comparable to wheat bran or millrun in nutritional value. Rye: Sticky droppings and poor growth result from feeding rye to young chicks, so that this grain is unsatisfactory as a feedstuff for young birds. Older birds can tolerate as much as ten per cent in the mash. Screenings from grain-cleaning op- erations may usually be substituted for cereals to the extent of five per cent of the mash. They vary greatly in composition and value, and should be used cautiously. Sorghum grains: Milo, Egyptian ("gyp") corn, kaffir, and other sorghums are important poultry feed grains in Cali- fornia. They are low in fiber and have high digestible-energy values. Milo may well be used in place of corn in California poultry rations when availability and comparative prices warrant. Feeding trials at this Station indicate that good quality milo has about 92 per cent of the feeding value of yellow corn in chicken rations. Water-grass seed, available from rice-cleaning processes, can be used ex- tensively in poultry rations when its cost is comparable to the cost of barley. Be- cause its fat becomes rancid quickly, it should be used as soon after grinding as possible. Wheat: This popular grain for poul- try in California ranks slightly below yel- low corn in feeding value, but is above barley and oats. But because it is so widely used as human food, it is often compara- tively expensive for use as poultry feed. Wheat by-products: The most im- portant wheat by-products are wheat bran, millrun, and middlings. These pop- ular poultry feedstuffs are lower in diges- tible-energy value than whole wheat, but they contain somewhat higher amounts of valuable proteins, minerals, and vitamins. These relatively cheap feedstuffs may be profitably used in many poultry rations. Digestible-Energy Values of the Common Grains In deciding which of the available grains to feed, the poultryman should consider their digestible-energy values for chickens. On the basis of calculations, 100 pounds of yellow corn contains total digestible nutrients (carbohydrates, pro- teins, fats) equivalent in energy-produc- ing value to 75.5 pounds of starch. Wheat has a corresponding value of 72.1 ; milo, 69.5; barley, 66.1 ; oats, 63.6. In other words, 105 pounds of wheat, 108 pounds of milo, 114 pounds of bar- ley, and 119 pounds of oats each have a digestible-energy value equivalent to 100 pounds of corn. Expressing the compari- son in percentage: wheat has 95.5 per cent the energy value of corn; milo has 92.0 per cent; barley 87.5 per cent; oats 84.3 per cent. Note that since protein concentrates such as fish meal, oil meals, and meat [18 scraps are used primarily as sources of protein rather than of energy, it is not necessary to rate them according to their digestible-energy values. Other Energy-Source Feedstuffs Carrots: Dried carrots, either whole or roots only, have been used successfully to replace grain to up to ten per cent of the ration. Grape pomace meal is too high in fiber to make a satisfactory feedstuff for chickens. Legumes (cull lima beans, mung beans, field peas, cow peas, pigeon peas, etc.) : Feeding trials at this and other stations have shown that these feedstuffs may be used to replace grain to up to five to ten per cent of the ration. Although these legumes contain 20 to 25 per cent protein, they are used primarily as energy sources. Molasses: Molasses (cane or beet), an energy concentrate, can be fed in small quantities when its price warrants. It should never be fed at levels higher than 2% per cent of the total ration, because it has a laxative effect. Molasses is rich in pantothenic acid and potassium, and helps reduce the dustiness of mashes, al- though it is difficult to mix into the ration. For easier mixing, dehydrated molasses may be used— four pounds are about equal to five pounds of liquid. Molasses may also be fed as molasses-bran, a mix- ture containing about 15 per cent mo- lasses. Orange meal: This has been sug- gested as a possible feedstuff, but tests made here have shown orange peel and pulp meal to be almost valueless for poultry. Potatoes: Small and otherwise in- ferior potatoes are sometimes fed to poul- try. About five pounds of potatoes are required to replace one pound of grain. They should be cooked before using. Raisins: Among the fruit by-products tested at this station are cull raisins. They can be used to replace grain to up to ten per cent of the ration. Safflower seeds and oil meal are sometimes available as poultry feedstuffs. They are high in fiber and are less valu- able than cereal grains as energy sources, but they furnish some fair-quality protein. Sunflower seeds are sometimes used in the scratch feed. The protein of the inner part of the seed is of excellent quality, but the high fiber content of the hull decreases the value of the seed. Tomato pomace meal is high in fat and fiber, and although it contains some carotene is not a recommended poultry feedstuff. Yeast culture is a feedstuff contain- ing a small amount of live yeast dried on ground grains. With some rations, the growth rate of cockerel chicks is increased slightly when two per cent yeast culture is added to the mash. The reason for this growth effect is not yet known. PROTEIN CONCENTRATES The protein content of the cereals is not sufficient to satisfy the needs of the chicken. Various protein concentrates are used to supply the additional needed pro- tein. For the chick, protein concentrates furnish about two-thirds of the total pro- tein of the diet, while for the hen they provide less than half of the total protein. Since protein requirements are actually the amino acid requirements considered together, it is often more convenient to speak of amino acid requirements simply in terms of protein requirements. The total protein requirement is about 20 per cent for young chicks and 15 per cent for adult birds. The protein must be present in digestible form, and it must furnish the required amounts of the various amino acids. Animal Protein Concentrates Animal protein concentrates are often sold on the basis of protein content, as [19 TABLE 5 — The amino acid composition of some feedstuff s, expressed as percentage of total feed stuff s. * Feedstuff Protein Arginine Lysine Methio- nine Cystine Trypto- phane Alfalfa meal 17 10 10 43 43 65 35 32 55 35 10 10 44 42 44 46 13 16 12 1.1 0.48 0.38 1.4 3.2 3.8 1.5 2.3 3.9 1.4 0.34 0.60 4.4 3.7 2.8 3.8 0.52 0.96 0.36 0.85 0.18 0.22 0.86 1.2 3.7 1.7 0.93 2.8 2.6 0.25 0.33 1.3 1.2 2.7 2.0 0.36 0.53 0.90 0.39 0.29 0.27 1.0 0.78 1.9 0.52 0.73 0.94 1.0 0.15 0.23 0.57 1.4 0.79 1.6 0.17 0.19 0.38 0.31 0.18 0.19 0.82 0.95 0.65 0.21 0.61 0.66 0.42 0.20 0.18 0.70 0.55 0.66 0.73 0.23 0.27 0.31 0.32 Barley 0.11 Corn 0.07 Corn gluten meal 0.34 Cottonseed meal 0.47 Fish meal 0.78 Fish solubles, condensed Linseed oil meal 0.14 0.55 Meat scraps 0.38 Milk, dried skim 0.46 Milo 0.08 Oats 0.13 Peanut oil meal 0.40 Sesame seed oil meal. . 0.63 Soybean oil meal 0.53 Sunflower seed oil meal Wheat 0.60 0.14 Wheat bran 0.24 Whey, dried 0.24 Ideal ration for chick growth .... 20 1.0 0.9 0.5 0.3 0.2 * Adapted from Almquist, H. J., The amino acid requirements of avian species, in Proteins and Amino Acids in Nutrition, p. 231, M. Sahyun, Ed., Reinhold (1948). determined by analysis. Where this method is followed, a unit of protein is equal to one percentage point of crude protein (the nitrogen content multiplied by 6.25; see page 4). Fish meals are made from whole bony fish or from fish cannery scrap, by a wet- rendering process: the raw material is cooked, and the mixture of water and oil is pressed out from the solids, which are then dried, ground, and sold as fish meal. The oil is separated from the water ex- tract and sold as feeding oil or for manu- facturing purposes, while the water- extract is often concentrated and sold as condensed fish solubles. If the fish meal is dried at a low temperature, the product will be highly digestible and have a high nutritional value. On the Pacific Coast most fish meal is made from the sardine (pilchard), her- ring, tuna, or mackerel. The proteins of these products are generally of good qual- ity: they provide all the essential amino acids in digestible form. These fish meals are usually good sources of arginine, lysine, and methionine, and can therefore be used to supplement proteins which are deficient in these amino acids. Shark meals have generally been found inferior to other fish meals as sources of protein for poultry. They con- tain appreciable amounts of urea, which contains nitrogen, but actually has no protein value for chickens (see page 4). Recently, however, a new process has been developed by which a shark meal of improved quality can be produced. Carp meal, raffish meal, and other fish meals are of fairly good quality when properly prepared. The available tonnage is limited. [20] Condensed fish solubles contain proteins which are low in certain amino acids, and are therefore inferior to most fish meals as protein sources for poultry. The main reason for using fish solubles and similar products in the ration is that they contain the animal protein factor (see page 10). Meat packing by-products are pro- duced by both dry- and wet-rendering processes. Meat scraps, the dry-rendered residues from animal tissues, and tank- age, the wet-rendered product, vary greatly in quality according to the raw materials used and the methods of manu- facture. They are generally good sources of arginine and lysine, but are usually deficient in cystine and methionine. Tank- age containing significant amounts of blood is also deficient in isoleucine. Blood meal protein is a good source of arginine and lysine, but is deficient in methionine as well as isoleucine. It is a good supplement for corn gluten meal protein, which is a good source of iso- leucine but is deficient in lysine and ar- ginine. Liver meal and liver and glandu- lar meal are fairly good sources of most amino acids, but like other meat packing by-products are often deficient in methi- onine and cystine. The chief use of these meals is to supply vitamins; other meat by-products are more important as amino acid sources. Milk products that are fed to poultry are usually dried or condensed by- products obtained in the manufacture of butter and cheese for human use. Fresh skim milk and buttermilk, however, are also satisfactory feedstuffs, if they are cheap enough. They should not be fed in metal containers. The cost per pound of dry matter, or the cost per pound of protein, are the factors which should de- termine whether a fresh, condensed, or dried product is to be used. Some milk products— such as dried whey— are low in protein, but are valuable in the ration because they contain signifi- cant amounts of riboflavin and other water-soluble vitamins. Vegetable Protein Concentrates Soybean oil meal, our most impor- tant vegetable protein concentrate, is a good source of all the amino acids except methionine (in which it is slightly defici- ent). The quality of soybean oil meal depends largely on proper heat treatment of the meal during or after removal of the oil from the beans. As a result of such treatment, the methionine of the soybean protein is made available to the chicken. If the meal is overheated, a portion of both the methionine and lysine becomes unavailable; feeding such overheated meal to chicks also tends to cause "pasting up," a condition characterized by sticky droppings which adhere to the down feathers around the vent. Properly heat- treated soybean oil meal is an excellent source of lysine, and is well used to sup- plement the cereal grains, sesame seed oil meal, and other vegetable protein con- centrates, which are low in lysine. When soybean oil meal is used to re- place fish and meat products in the ration, care must be taken to provide riboflavin, the animal protein factor, and minerals, particularly calcium and phosphorus. Raw soybeans should not be fed to chickens, mainly because the methionine they contain is largely unavailable. Sesame seed oil meal, like soybean oil meal, is produced by removing the oil from the seeds. But unlike soybean oil meal, sesame seed oil meal does not re- quire heating to allow utilization of all its amino acids. Sesame seed protein con- tains a large amount of methionine but only a small amount of lysine. It is best used together with some product which is a good source of lysine but is deficient in methionine. A mixture of two parts soy- bean oil meal to one part sesame seed oil meal is an excellent source of amino acids [21 for the growing chick. The mixture, how- ever, does not cover the lysine deficiencies of the cereal grain proteins which are also present in the diet. Sunflower seed oil meal, the most complete vegetable protein concentrate known, provides adequate amounts of all the amino acids. However, it does not con- tain the excess of lysine required to cover the deficiency of the cereal grains. An excellent source of methionine, it is best used as a supplement to soybean oil meal. Corn gluten meal, a by-product of the manufacture of cornstarch, is not a very good protein source for poultry be- cause it is low in arginine, lysine, and tryptophane. For best results it should be used with such a product as tankage or blood meal. Peanut oil meal is a poor source of methionine and lysine and is therefore one of the poorer sources of protein for poultry, unless properly supplemented. Cottonseed meal, which is deficient in lysine and methionine, can be used in mashes for growing birds but should not be fed to laying hens because it causes mottled or olive-colored yolks in fresh eggs and "pink whites" in storage eggs. Linseed oil meal contains an uni- dentified substance which retards the growth of chicks. The addition of the vi- tamin pyridoxine to the ration will coun- teract the action of this substance, as will soaking the linseed oil meal in water for 12 hours. Properly processed linseed oil meal has been found to be a good source of all the required amino acids except lysine. MINERAL SOURCES The minerals requiring the greatest atten- tion in poultry rations are calcium, phos- phorus, manganese, sodium chloride (common salt), and iodine. Certain ani- mal products (for example, meat and bone scraps, fish meal) contain fairly large amounts of these minerals, but most vegetable feedstuffs are poor sources. Minerals, like other feedstuffs, should be purchased on the basis of price and qual- ity. It is unnecessary to buy expensive mineral mixtures for poultry. Calcium and Phosphorus A calcium supplement is usually added to mashes as calcium carbonate, in the form of ground limestone, calcite, or oyster or clam shell. The cheapest-per- pound source of calcium should be used. Laying hens need fairly large amounts of calcium for egg-shell formation, and therefore hoppers containing crushed limestone or shell should be available to the hens at all times. Dolomitic limestone should not be used because it has a high magnesium content. It is important to note that none of these calcium sources is a substitute for the hard, insoluble grit which poultry receiving whole grains require. Bone meals are used primarily as phosphorus supplements, but they also contain large amounts of calcium. Special steamed bone meal is the form most com- monly available. Defluorinated rock phosphate (rock phosphate from which most of the fluorine has been removed) is a suitable calcium and phosphorus supplement for poultry. By definition it contains no more than one part of fluorine to 40 parts of phosphorus. The total poultry ration should contain no more than 0.035 per cent fluorine. If it is necessary to use raw rock phosphate only small amounts should be used. Dicalcium phosphate may also be used as a source of calcium and phos- phorus in poultry rations. It is prepared by dissolving bone meal or phosphate and precipitating the dicalcium phosphate in pure form. Phosphatic clay (soft phosphate with colloidal clay) contains approxi- mately 18 per cent calcium, 8.5 per cent phosphorus, and 1.2 per cent fluorine. Like other phosphate products, it should [22] S5 CO CO W • CO : io : ; *- C §a 8 rH tH iH CO iH OS *H . *H . . H id o w o o 4- 5 c a w 2 • NHH00 00 lO iH lO CD tJ< t- CO J? 4) 2 T5 > C II OCOCOIO HO^J 1 00 CO iH 00 oo -co 73 OS "# ^ O "* OHNP5WO CO t- t- Ci CO O CO iH tH o N O rH r-J t d "3 u rlrlHO©H00OOOOlOO00OO00OHOOOON0! o ; d d o th th a eg © CQ iH CO iH CO k U A n o c E 1 0> X i I o3 w bo ■J CO s e < ^ »^ *- 1 01 3 o 02 T> •d 8 «;§ ID O 15 6 1 1 XJ ■e X* m a> 1 X» 01 fl 1 o o oT "5 B ■3 1 s w a ee t- o a, g ll c "3 e o a; > 5 . -a a a E 1 i n- XI 4. •rl i- T3 is a to si ll J3 O c3 a> a> ^s s c8 e8 cd > c8 c^ c^ T < 03 03 i§ o: II J73 w 5«« a o d^ ills ijj D K be purchased on the basis of cost per pound of phosphorus. Manganese The chicken's manganese requirement is so high that even though some feed- stuffs are fairly good sources of manga- nese (see Table 6), it is necessary to add manganese to the ration. Four to eight ounces of feeding grade manganese sul- fate are usually added to each ton of mash. The amount to be added will depend upon the other ingredients of the mash, the purity of the manganese source, the age of birds, and the feeding method used. For example, four ounces manganese sulfate per ton are sufficient in an all-mash ration, but when a mash is to be supplemented with whole grains, eight ounces manga- nese sulfate per ton are required. Grains are usually poor sources of manganese. Salt Salt for poultry should be fine in tex- ture, free-flowing, and evenly mixed into the mash. Iodized salt (containing at least 0.007 per cent iodine) should be used in starting and breeding rations, unless five per cent or more of fish meal is used. Oyster or clam shell fed to breeding hens will supply sufficient iodine to meet the requirement. VITAMIN SOURCES In addition to the vitamins supplied to poultry rations by the cereal grains, green feeds, and protein concentrates, supple- mentary sources of vitamin- A, vitamin D 3 , riboflavin, and the animal protein factor are often needed. Fish oils of standardized vitamin A and vitamin D 3 potencies are commonly used as supplements in the ration. Oils should be fresh and of a potency guaran- teed by chick assay for vitamin D. They should be stored only in a cool, dark place. Dry vitamin A and D supplements containing guaranteed amounts of vita- mins A and D 3 may be preferred to the fish oils because they are more easily mixed with the other feedstuffs. However, comparative price per vitamin unit should be the chief factor in determining which supplement is used. Milk products: Dried skim milk, dried whey, dried buttermilk, and liquid milk products are valuable sources of protein and the B-complex vitamins. Milk products may be used to supply ribo- flavin, pantothenic acid, and choline to poultry rations (see Table 6) . Milk prod- ucts also supply a limited amount of the animal protein factor which is required for chick growth and hatchability. Fermentation products resulting from microbial activity are often good riboflavin sources. Fermentation prod- ucts are now being developed as sources of other vitamins also, particularly of the animal protein factor. Use of such prod- ucts should be determined by analysis of each product, since the vitamin content of different products is likely to vary con- siderably. Liver meal is a fairly rich source of riboflavin, pantothenic acid, choline, and the animal protein factor. Liver and glandular meal is usually less valuable as a vitamin source than liver meal. Synthetic vitamins: Synthetically produced riboflavin, choline, vitamin D 3 and other less important vitamins are available for poultry feeding. These prod- ucts may be used when their costs com- pare favorably with natural products. In making such a comparison the poultry- man should remember that the natural sources of these vitamins usually provide other valuable nutrients too. GREEN FEEDS Green feeds are difficult to classify as energy or protein or vitamin sources, be- cause they supply all of these nutrients. The most valuable contribution of either fresh or dried greens, however, is caro- tene (the plant equivalent of vitamin A) . [24 Dried Greens Dried greens such as alfalfa meal and dried, young grasses (oat, wheat, barley, and lawn grasses) , can be used more con- veniently than fresh products, but they are also more likely to vary in quality, particularly in carotene content. Machine dehydration should be carefully con- trolled in order to minimize heat damage to the proteins. Fresh Greens Both carotene and riboflavin are sup- plied by fresh greens such as alfalfa, clover, lawn clippings, green oats, green barley, green wheat, Sudan grass, kale, chard, green lettuce, young corn, or beet tops. In California, alfalfa can generally be depended upon during much of the year. Ladino clover is an excellent green crop that may out-yield alfalfa on some light soils; but it is shallow-rooted and demands frequent irrigation. Sudan grass may prove the best summer green- feed crop where water for irrigation is limited. Actually, tests of the various types of fresh greens for vitamin A activity show that there are no great differences in value, and the poultryman can use what- ever green feed he can grow or buy most economically. All green feeds should be cut when young and tender, because at this stage they are highest in nutritional value. With careful planning, many Cali- fornia poultrymen can provide a year- round daily supply of tender greens for their birds. Fresh greens, however, are desirable but not absolutely necessary supplements to the poultry ration. Growing pullets— particularly those over three months of age— may well be given all the greens they will eat. Laying hens should be limited to five pounds of fresh greens daily for each 100 birds, since more than this amount will make the egg yolks too dark for most commercial markets. The practice of placing the birds on properly rotated green pastures is excel- lent for growing pullets but is not recom- mended for laying hens. Adult birds on pasture may destroy more green feed than they eat. Also, hens given unlimited amounts of green feeds will produce eggs of uneven yolk color. Caution: Keep laying hens from eat- ing cheeseweed (mallow). Consumption of this plant by hens has been shown at this Station to cause "pink white" deteri- oration in storage eggs. Cheeseweed often grows along roads and fence rows at the edges of fields. It may also be present in products such as dried alfalfa unless these are kept free from weeds. Other sub- stances causing "pink white" include tree mallow, hollyhock, cottonseed meal, and kapok meal. Silage In dry-farming areas, or where irriga- tion water is not available, cereal grasses and other green crops which will grow during the rainy season may well be en- siled. The birds may not eat silage read- ily at first, but most flocks will soon learn to eat four to five pounds per day for each 100 hens. This is about the maxi- mum amount that can be fed without adversely affecting egg yolk color. Silos used on poultry ranches must have small diameters ; otherwise the silage may spoil faster than it can be fed. The use of 50 to 60 pounds of molasses per ton of grasses will help preserve the product. HARMFUL COMPONENTS OF FEEDSTUFFS Harmful compounds are widely dis- tributed in natural feedstuffs, and in the formulation of rations they must be con- sidered separately from the recognized nutrients. Often these harmful substances are destroyed in processing or consumed in such small amounts that they cause no great harm. Besides, one feedstuff may [25 contain a substance capable of counter- acting the harmful effects of another, so that the complete ration will have no in- jurious results. Grains raised in certain areas of north central United States may contain poi- sonous amounts of selenium. The tox- icity may be reduced by supplementing the ration with proteins, but in any event such grains can be safely fed only in lim- ited amount. Excessive amounts of fluorine may be present in rock phosphate; some of this must be removed (defluorinated) or the feeding level must be kept very low. Alfalfa contains a factor which de- presses growth in young chicks, and the level must therefore be kept below 5 per cent of the chick ration if most rapid growth is to be obtained. Growing pullets and laying hens can tolerate higher levels. Raw soybean meal will not allow good growth of chicks because its methi- onine is unavailable. The difficulty may be overcome by the addition of the amino acid methionine, or by proper heat treat- ment of the meal, which will destroy the harmful factor or factors controlling the methionine. Linseed oil meal contains a growth- inhibiting compound. The effect of this compound may be counteracted by in- creasing the level of pyridoxine in the ra- tion; or the compound may be destroyed by processing the meal with water. Charcoal should not be used in the ration because it may destroy or make unavailable some of the vitamins, espe- cially vitamin A and riboflavin. Chocolate meal has been found to be harmful to chickens, and should not be used. SOCGiSUD Hid FORMULAS AND HtntHG METHODS As an aid to the compounding of high- quality, inexpensive feeds, we suggest below a number of sample formulas for birds of different ages and uses. We have considered some variations in relative costs and availability in developing these formulas, but it is entirely possible that under certain conditions other combina- tions of feedstuffs will prove better than these. CHICK-STARTING MASHES The chick-starting mashes listed in Table 7 are designed for use with chicks which are to be reared primarily for egg pro- duction. These mashes conform to the allowances presented in Table 3. A mix- ture of two or more ground grains (corn, wheat, barley or sorghums) should be used, but the proportions may be varied as current prices warrant. These mashes will contain approximately 20 per cent crude protein and should not be diluted with other feeds until the chicks are six weeks old, when whole grains may be fed in small amounts (up to one-fifth the weight of the mash) . The amount of grain fed may be gradually increased, until the birds are receiving equal amounts of mash and grain at 12 weeks. When whole grains are fed, the birds should be given hard, insoluble grit to aid the gizzard in its grinding function. BROILER-FRYER MASHES The formulas for broiler-fryer mashes given in Table 8 have been found to pro- mote the rapid growth necessary for meat birds. These formulas contain low levels of fibrous cereal materials (barley and mill feeds) and alfalfa meal (which con- tains growth inhibitors as well as a high level of fiber) , hence are different from the formulas suggested for replacement birds. These mashes are calculated to conform to the allowances presented in Table 3. [26 TABLE 7 — Formulas for representative chick-starting mashes. Ingredients No. 1 No. 2 No. 3 No. 4 No. 5 Fish meal, 65% crude protein . . . Soybean oil meal Alfalfa meal 1 Dried skim milk Dried whey Salt Wheat bran or mill run Ground grains Manganese sulfate, 85% pure. . Ground limestone or shell Bone meal, special steamed (or equivalent phosphorus source). Vitamin D 3 source (400 units per gram, or 181,000 units per lb.) 3 Riboflavin 4 lbs. per ton 200 150 100 10 320 1178 M 40 2 0.8 gram lbs. per ton 150 250 100 50 10 240 1153 M 45 2 0.4 gram lbs. per ton 100 350 100 50 50 10 160 1128 M 40 10 2 0.2 gram lbs. per ton 60 500 100 15 2 160 1103 40 20 2 1.0 gram lbs. per ton 40 500 100 100 15 2 160 1023 M 40 20 2 1 Should contain carotene equivalent to at least 67,000 International Units of vitamin A per pound. 2 Iodized salt, containing 0.007 per cent iodine, is advised when high levels of soybean oil meal or limited amounts of fish meal are used. 3 Other potency products may be used to supply the same amount of vitamin D3. For example, only 0.4 pound is required if the product contains 2000 A.O.A.C. units per gram, or 908,000 A.O.A.C. units per lb. 4 Any riboflavin supplement may be used if it supplies the specified amount of riboflavin per ton (1 gram = 1000 milligrams [mg.]). Amounts of riboflavin or other supplements, which are added in very small amounts, should be premixed with ground grains or soybean oil meal before mixing. TABLE 8 — Suggested formulas for broiler-fryer mashes. Ingredients No. 6 No. 7 No. 8 Fish meal, 65% crude protein Meat scraps, 55% crude protein Soybean oil meal Sesame seed oil meal Alfalfa meal Wheat bran or mill run Corn, yellow, ground Milo, ground Barley, ground Wheat, ground Bone meal, special steamed (or equivalent phos- phorus source) Limestone or shell flour Salt Manganese sulfate, 85% pure Fermentation product containing at least 100 milligrams riboflavin per pound Riboflavin Vitamin A source (3000 International Units per gram, or 1,362,000 Int. Units per pound) Vitamin D 3 source (400 A.O.A.C. units per gram, or 181,000 A.O.A.C. units per pound) 3 lbs. per ton 100 75 300 50 1 200 500 300 400 40 10 H 20 lbs. per ton 240 200 200 80 1 800 240 200 20 20 2 H lgram 2 lbs. per ton 190 250 80 900 100 310 15 40 10 V2 2 grams 1 Should contain carotene equivalent to at least 67,000 I.U. of vitamin A per pound. 2 Iodized salt, containing 0.007 per cent iodine, is advised when high levels of soybean oil meal or limited amounts of fish meal are used. 3 Products of other potencies can be used (see footnote 3, table 7). TABLE 9 — Suggested formulas for laying mashes. Ingredients No. 9 No. 10 No. 11 No. 12 No. 13 Fish meal, 65% crude protein . . . Meat scraps, 55% crude protein . Soybean oil meal Dried whey Alfalfa meal 1 Bone meal, special steamed (or equivalent) Ground limestone or shell Salt Wheat bran or mill run Ground grains Manganese sulfate, 85% pure. . . Vitamin A source (3000 Int. Units per gram) Vitamin D 3 source (400 A.O.A.C. units per gram) lbs. per ton 200 250 120 20 50 20 300 1040 4 3 10 J is. per ton 100 400 100 40 40 20 160 1124 10 lbs. per ton 80 450 100 45 40 20 2 160 1089 10 lbs per ton 40 50 400 50 100 35 40 20 2 200 1050 V2 10 lbs per ton 100 450 50 100 30 30 20 2 200 1005 10 1 Should contain carotene equivalent to at least 67,000 I.U. of vitamin A per pound. 2 Iodized salt, containing 0.007 per cent iodine, is advised when high levels of soybean oil meal or limited amounts of fish meal are used. 3 May be supplied by products with different potencies (for example, 2.4 pounds 5000 I.U. vitamin A product plus 2 pounds 2000 vitamin D product or 10 pounds 1200 A, 400 D product). TABLE 10 — Suggested mash formulas for breeding hens. Ingredients No. 14 No. 15 No. 16 Fish meal, 65% crude protein Meat scraps, 55% crude protein Soybean oil meal Dried whey Alfalfa meal 1 Bone meal, special steamed (or equivalent) Ground limestone or shell Salt Wheat bran or mill run Ground grains Manganese sulfate, 85% pure Vitamin A source (3000 Int. Units per gram) .... Vitamin D 3 source (400 A.O.A.C. units per gram) Riboflavin 4 lbs. per ton 200 250 120 20 50 20 300 1026 Vi 43 10* 1.6 grams lbs. per ton 100 400 50 120 40 40 20 2 160 1056 Yv 4 10 1.4 grams lbs. per ton 50 50 400 100 120 30 40 20 2 200 976 Vi 4 10 1.0 gram 1 Should contain at least 67,000 I.U. of vitamin A activity per pound. 2 Iodized salt, containing 0.007 per cent iodine, is advised when high levels of soybean oil meal or limited amounts of fish meal are used. 3 May be supplied by products with different potencies (for example, 2.4 pounds 5000 I.U. vitamin A product plus 2 pounds 2000 vitamin D product or 10 pounds 1200 A, 400 D product). 4 Any riboflavin supplement may be used which supplies the specified amount of riboflavin per ton. 28 When grain is appreciably cheaper than mash, it may be profitable to dilute the broiler mash with whole grains after the sixth week. If this is done, hard, in- soluble grit should also be made avail- able to the birds. Not more than one- fourth of the ration should be made up of whole grains. LAYING MASHES Representative formulas for laying mashes, which appear in Table 9, contain about 20 per cent crude protein and also conform to other standards of Table 3. These mashes are designed to be fed with supplemental grains in the ratio of half mash to half grain, during periods of high production. Crushed limestone or shell, and hard, insoluble grit should be fed free choice. If an all-mash ration is de- sired, the amounts of ground grains may be increased by 1500 pounds for a 3500- pound mix. By omitting the ground grains from these formulas, the poultry- man has a concentrate which may be used satisfactorily with grains raised by him- self or bought locally. BREEDING MASHES Breeding mashes differ from laying mashes only in that they contain higher- levels of riboflavin, the animal protein factor, and other water-soluble vitamins. Grains, calcium sources, and grit should be fed in the same manner as with laying mashes (above). Representative formulas are given in Table 10. ALL-PURPOSE MASHES The preceding formulas are for specific purposes, but the differences between them are small. It is obvious that it is not absolutely necessary to use different for- mulas for each stage of growth and devel- opment. In fact it may be unprofitable for a farmer who mixes his own feed to make several formulas. A larger mixer, how- ever, may effect some savings in cost by making several mashes. TABLE 1 1 — All-purpose mash formulas. Ingredients Corn, yellow, ground Wheat, ground Barley, ground . '. Alfalfa meal, dehydrated Wheat bran or mill run Soybean oil meal, 44% protein Fish meal, at least 65% protein Dried whey Dried skim milk Liver meal Limestone or shell, ground Bone meal, special steamed . . Salt Manganese sulfate, 85% pure . Feeding oil (400D-3000A) Riboflavin Starting and growing Laying and breeding lbs. per ton lbs. per ton 600 200 270 200 200 600 80 150 300 300 200 200 150 150 50 50 50 50 40 40 30 30 24 24 10 10 . v* V2 5 5 2 grams 2 grams 2,009 }/ 2 lbs. 2,009 Y 2 lbs. [29 A basic mash formula has for some years been fed successfully throughout the bird's whole life at this Station. The only time the formula is changed is when the pullets are about five months old. At this time the level of corn is reduced from 600 to 200 pounds per ton, and the barley is increased by an equal amount; also, the level of alfalfa meal is increased to 150 pounds and the wheat reduced to 200 pounds. A mixture of approximately equal parts of whole corn, wheat, and barley is fed from the sixth week onward. The amount of grain fed is gradually in- creased until the birds are receiving equal amounts of mash and grain at 12 weeks. The grain is fed twice daily in the litter. Since this mash is also used for breeding hens, its vitamin levels are quite high. The formulas for this all-purpose mash are given in Table 11. Note: This formula was designed to supply excesses of both water- and fat- soluble vitamins, because at the time of its development we did not know the bird's exact requirements for these nutri- ents. Now that these requirements are more exactly known, the amounts of vita- mins in the mash can safely be lowered. The basic formula as given above has been changed very little at this Station, however, because most of the birds raised on the mash are used for breeding ex- periments. In breeding experiments it is necessary to maintain as constant an en- vironmental condition as possible from one year to the next. For a further discussion of feeding methods, see the mimeographed publica- tion "What Is the Best Way to Feed Chickens?" obtainable from the Division of Poultry Husbandry, University of Cali- fornia, Berkeley 4. 40m-ll,'49(B5323) 30] fU ajtfM&buia, AGRICULTURE • . • Contains brief, easy-to-read progress reports of agricultural research, and is published monthly by the University of California College of Agricul- ture, Agricultural Experiment Station. FIELD CROPS ORCHARDS TRUCK CROPS LIVESTOCK CALIFORNIA AGRICULTURE offers information useful to the farmer and food processor, together with announce- ments of other publications dealing with farm subjects as they are issued by the College of Agriculture. Upon your request, your name will be added to the mailing list to receive CALIFORNIA AGRICULTURE with- out cost. Send your name and address to: California Agriculture, Publications Office, College of Agriculture, University of California, Berkeley 4, California