• * * .v y J CnV n£ .0*0- ^ & /av^v v/ /jfiter-. v*** MYS1 "°° 1T ... V«V • • * .V* o " o *bv^ :£M&* ^o*" •-SiliSr. v o^ \/ *dta «w .vsk*. \/ /dta ' .. V*^V %*^-V V^V %. 1 V^V o » » v-o^ ST- ther kinds of animals, and until recently they nave received little lystematic study from competent scientific men. The investigations, of which an account is presented in this bulletin, »pen up a new field for scientific inquiry. While the work which has >een accomplished is but the first step, it reveals how little has been blown and how much is to be learned in regard to the diseases of )irds. The greater part of the losses from infectious diseases in the >oultry yard may probably be prevented by the intelligent application >f proper sanitary measures. Until the nature of these diseases is learly understood, however, it is impossible to intelligently formulate preventive measures or to prescribe successful methods of treatment. The financial investment in domesticated birds is of such magnitude, md the products are marketed in such vast quantities, and are so isseutial to the well being of every citizen that the problems affecting his industry are deserving of the most careful study and investi^a- ion. The researches herein reported have been made in i he hope and expectation that they would be continued until practical means of pre- senting the common infectious diseases are placed within the reach of II engaged in the poultry industry. Very respectfully, D. E. Salmon, Chief of Jin rea a of Animal Industry. Hon. J. Sterling Morton, Secretary of Agriculture. § LETTER OF SUBMITTAL. U. S. Department of Agriculture, Bureau of Animal Industry, Washington, D. C, April 2, 1895. Sir : I have the honor to submit herewith some preliminary studies of infectious diseases among poultry, including fowls, turkeys, and pigeons. Though these studies have not yet reached that state which permits us to recommend any well-defined preventive or curative meas- ures, it is to be hoped that they will give those immediately interested a better insight into the nature of some of these diseases, besides fur- nishing investigators throughout our country a more secure basis for further experimentation. Very respectfully, Theobald Smith, Chief of Division of Pathology. Dr. D. E. Salmon, Chief of Bureau of Animal Industry. 4 TABLE OF CONTENTS. Page. An Infectjous Disease among Turkeys Caused by Protozoa (infectious entero-hepatitis). By Theobald Smith 7 Special characters of the disease 8 The micro-organism {Amoeba meleagridia n. sp., 1895) 15 The relation of bacteria to the disease 21 The relation of this disease to certain other diseases of poultry 22 General conclusions 24 Appendix 27 A Preliminary Investigation of Diphtheria in Fowls. By Veranus A. Moore 39 Outbreaks 42 Bacteria associated with the lesions 53 Description of the nonmotile bacillus 5G Prevention and treatment 58 The relation of diphtheria in fowls to public health 60 Conclusions 61 A Study of a Bacillus Obtained from three Outbreaks of Fowl Cholera. By Veranus A. Moore 63 History of the outbreaks 64 Description of the bacillus 65 The nature of the inoculation disease 67 On a Pathogenic Bacillus of the Hog-Cholera Group Associated with a Fatal Disease in Pigeons. By Veranus A. Moore 71 History of the disease 71 Description of the bacillus 73 5 LIST OF ILLUSTRATIONS. Facing page. Plate I. Photographic reproduction of the caecum ami the spleen from a turkey affected with the protozoan disease 78 II. Drawings of normal and diseased caeca and of tbe spots on the liver. 80 III. Recent and advanced stages of the liver disease 82 IV. Microscopic appearance of the diseased ca'cum and liver with the microparasites shown 84 V. Drawings showing microparasites, giant cells, and ilagellatesfrom the blood 86 VI. Drawings showing the diphtheritic lesions in the mouth and on the cornea of a fowl 88 INVESTIGATIONS CONCERNING INFECTIOUS DISEASES AMONG POULTRY. AN INFECTIOUS DISEASE AMONG TURKEYS CAUSED BY PROTOZOA (INFECTIOUS ENTERO-HEPATITIS). By Theobald Smith. [Platen I to V, inclusive.] In the full of 1S93 the writer received from Mr. Cushman, of the Rhode Island Experiment Station, the organs of an adult turkey in which the liver and the casca were very extensively destroyed by a peculiar disease. A second case was sent by Mr. Cushman in April ot 1894, in which the same disease was recognized. In June of 1894 the writer found the same affection in a very young turkey in western Massachusetts. The changes induced by this affection were so pecul- iar and yet so uniform in these three cases that a specific infectious disease could not but suggest itself on even superficial examination. A careful study of this material convinced the writer that the cause of this disease was a protozoan parasite not hitherto recognized. It was, therefore, deemed best to investigate the disease more thoroughly, and for this purpose the writer spent three weeks at the Ehode Island Sta- tion during the mouth of August. The turkeys were obtained by vol- untary contribution and by purchase, mostly from localities within 5 to 10 miles of Kingston, R. I. Some came from a greater distance. In this work I was greatly assisted by Mr. Cushman, in charge of the poultry work, and by Professor Flagg, director of the station. The chemical apparatus of the station was placed at my disposal by Professor Wheeler. With the aid of the apparatus brought from Washington and that on hand I was enabled to make a careful examination of about 50 tur- keys. Of these, IS were affected with the specific protozoan disease, and many of the rest were affected with other diseases, briefly referred to under each case. The short space of time which could be devoted to this subject did not enable the writer to do more than to make a preliminary study of the disease and its cause and to collect material for further study. 7 8 INFECTIOUS DISEASES AMONG POULTRY. Now that a firm basis for the investigation of the practical problems has been secured, it is to be hoped that the investigation will be prose- cuted during the coming summer, both at the experiment station of the Bureau and elsewhere. The publication of the work thus far done will also enable the various experiment stations to make observations on the communicability of the disease and on means for its eradication. The external appearances of the turkeys affected with the disease do not seem to be constant, and this is not to be wondered at in view of the varying intensity of the changes found in the internal organs. In Rhode Island the disease is known as " blackhead," owing to certain peculiar discolorations which take place at the height of the disease. While it might be well to retain this as a popular name, we do not believe that all cases of blackhead have the specific disease herein described, nor do all turkeys affected with this disease manifest the appearances of blackhead. More extended study is needed before we may rely upon symptoms as a means of recognizing this disease during life, especially as there are several other affections of turkeys quite distinct from this concerning which there exists as yet very little defi- nite information. As brought out more fully further on, the disease may be recognized by anyone who has made himself familiar with the salient facts in this article by an examination of the organs of the diseased turkey after death. Among the symptoms which may be expected to appear sooner or later, diarrhea probably occupies a prominent place. The disease of the caeca is responsible for this. Yet we may have diarrhea with at least one other disease of the creca, and the presence of tapeworms may also cause this disturbance. Emaciation was not constantly present in the cases dissected by me. As it may accompany other wasting diseases, it can not be depended upon as a sign of this affection. Leaving this part of the subject we shall turn to those characters of which the investigations have given some definite information. SPECIAL CHARACTERS OF THE DISEASE. The disease seems to attack turkeys when quite young. In early June I found a turkey about 3 weeks old (No. 3) in which the dis- ease had already made considerable progress. It seems, moreover, as if the disease were contracted only by the young, because in the examination of turkeys of different ages the oldest showed lesions of the longest standing; that is, such as had undergone the most exten- sive transformation. In general it may be said that the age of the turkey corresponded with the age of the disease process. The most serious and extensive destruction of tissue was noticed in the turkeys in fall. In midsummer the disease was making most progress; that is, it was freshest and the microparasites present in great numbers. It is probable that the delicate tissues of the young are best adapted for SPECIAL CHARACTER OF THE DISEASE. 9 the temporary habitat and rapid multiplication of this parasite. In this regard it simply follows the rule observed by large numbers of parasites, whose most destructive action is visited upon the young. The primary seat of the disease are the cseca. From these the liver is invaded. Other organs are not attacked. The caeca of the turkey in the normal condition are represented by two blind tubes opening into the intestine at a point about 6 inches from the cloaca (PI. II, tig. 1; PL I, fig. 1). They are directed toward the head, the blind end being nearer the gizzard than the opening into the intestine. They lie on either side of the latter, closely bound to it by mesenteries. The tips only are free. The length of the caeca varies according to age. In turkeys 3 months old they are about 8 inches long, while in those nearly a year old they are from 10 to 12 inches long. 1 The caeca are of nearly the same diameter as the intestine. When only slightly filled they are 4 to 5 mm. (one-sixth inch) in diameter. They may, however, be distended with feces to three times this diam- eter. The structure of the walls seems to be identical with that of the intestine to which they are attached. The communication between caeca and intestine is somewhat contracted. Near it in each tube there is a convex elevation about one-half of an inch long which is composed of lymphatic tissue. Its surface is usually deeply pigmented. Other lymphoid structures are represented by small elevations only three- sixteenths of an inch in diameter, usually pigmented and scattered sparsely over the mucous membrane. The mucosa itself is folded in longitudinal ridges, which are frequently pigmented. The caeca usually contain feces in greater or less abundance which are pasty, homogeneous in texture, and greenish in color. Under the microscope they appear to be composed mainly of bacteria. When the feces have a softer consistency numerous flagellates of several distinct forms may be detected in active motion in the feces of the recently killed bird. They appear to increase in number with the increase in the watery constituents of the feces. Coccidia have also been detected. They were present in No. 3 and in another young turkey of the same flock which died from some unknown cause. In the caecal contents of No. 17, which was free from disease, similar bodies were found, the largest measuring 32 by 18 //. They were in form and structure like Coccidium oviforme of the rabbit's liver, and perhaps identical with the form seen in the caeca of fowls by Eivolta and Silvestrini and named C. tenellum by Eailliet and Lucet. 2 It is very improbable that these bodies stand in any genetic relation to the true microparasites of the disease herein described. The lesions of the caeca are in substance a thickening of the wall, 1 The length of the intestine from gizzard to opening into ca?ea is about 5 feet for turkeys 3 months old and 8 feet for those nearly a year old. 2 Zoologie Medicale, second edition. 10 INFECTIOUS DISEASES AMONG POULTRY. followed in most cases by a destruction of the epithelium and deeper portions of the mucous membrane. This destruction results in the outpouring of a coagulable fluid into the tube (PL I, fig. 1; PI. II, figs. 2, 3, and 4). The thickening of the wall may vary considerably in extent from case to case. It may be uniform over the greater portion of the tube or it may be limited to circumscribed patches. The com- monest seat of these lesions is near the bliud end of the tube, where it evidently starts and from whence it spreads to other portions. Not infrequently only one caecum was found diseased, the other normal. This exemption was not due to mildness of the attack, for the other caecum may, in such cases, be the seat of very extensive changes. Thus of 18 cases only 11 had both caeca involved. The affection of the caecum is due primarily to the multiplication of the microorganism to be described below, within the walls of the caecum. The multiplication may take place chiefly in the mucous mem- brane, or in the submucous tissue, or it may, though rarely, extend into the muscular coat. The thickening of the wall is the result of several processes — the multiplication of the parasites, the increase of the normal tissue elements, and later on the accumulation of masses of small cells and some giant cells. In the early stages of the invasion the adenoid tissue between the tubules and in the submucosa becomes greatly increased, owing to the presence of large numbers of microparasites of round or slightly oval outline and from 6 to 10 jj. in diameter which stimulate the proliferation of the tissue cells. Numerous mitoses have been seen in this stage. The parasites seem to occupy the meshes of the adenoid tissue either singly or in groups or nests (PI. IV, figs. 1, 2). In these meshes they are soon enveloped in cells acting as phagocytes, so that the appearance of an intracellular habitat of the parasites is suggested, which is, how- ever, only an appearance and not demonstrated by further study. The presence of the parasites in this reticulum probably stimulates also the accumulation of lymph cells within the spaces, in virtue of which the mucous membrane is thickened. In this early stage of inva- sion the epithelium, both of the tubules and of the surface, remains unaffected. The parasites do not invade the epithelium at anytime. As the disease progresses there is a continued increase in the cellu- lar elements of the mucous and submucous coats and a gradual invasion of the muscular coats. Here the bundles of fibers of the circular coat are thrust apart by masses of cells, so that this coat also becomes greatly thickened. The inflammation finally extends to the serous covering, where the blood vessels become greatly dilated and give the cajcum a congested appearance. In cases of ordinary severity the wall of the caecum, not more than 0.2 to 0.5 mm. (one one hundred and twenty-fifth to one-fiftieth inch) thick normally, according to distention, becomes 2 to 3 mm. (one-twelfth to one-eighth inch) thick. SPECIAL CHARACTER OF THE DISEASE. 11 With the progress of the disease the mucous membrane may be shed and a coagulable fluid poured out into the caecum. In some cases it appears in isolated masses, which adhere to certain spots of the mucous membrane. In others, this exudate tills the entire tube with a yellowish- white mold (PI. II, tigs. 2, 3). This is built up in concentric layers, and consists of a mixture of blood corpuscles, fibrin, and masses of small round cells, in variable proportion. In the further progress of the local disease it is not improbable that bacteria are also concerned. The exudate contains immense numbers of them and the denuded mucosa furnishes a favorable place of entry. It is otherwise difficult to explain the continued increase in thickness of the walls of the caecum after the mucous membrane has been shed. This continued increase in thickness is due to an extensive infiltration of small round cells and the presence of some giant cells. Parasites in this advanced stage are scarce, ami usually recognizable only as vacuole-like bodies within the giant cells. The thickening of the wall is associated in some cases with an exten- sion of the inflammation to the contiguous wall of the intestine, which is thereby firmly attached to the caecum. Yellowish exudates are some- times found outside of the diseased caecum on its serous covering and they bind it inextricably to the other caecum or to the intestine or at- tach it to the abdominal wall. In these stages the inicroparasite is not found. It seems to have done its work by destroying the mucous membrane and to have left the field for miscellaneous bacteria. In no case were oilier regions of the digestive tract affected. Though the inflammation set up in the affected caecum may have extended through the wall to the contiguous intestine and caused the formation of a large amount of neoplastic tissue between the adjoining tubes, the disease did not invade the submucous or mucous membrane and the specific parasites were absent. Associated with this peculiar disease of the caeca is a more or less serious disease of the liver. In the 18 cases of protozoan disease the liver was very extensively diseased in 10. In two cases only small sclerotic foci were present and in these the lesions of the caeca were evidently at a standstill, or in a condition of active cicatrization. The affection of the liver is in tact a valuable means of recognizing this disease, for wherever it is present we may safely infer that we have the protozoan disease before us. The reverse is, of course, not neces- sarily true. The disease of the caeca may be so restricted that the secondary liver disease does not appear. Nevertheless, the value of the liver affection is indicated by the fact that in the few cases of c;ecal affection in which the disease was of a different character no changes in the liver were manifest (Nos. 25, 41). The appearance of the liver in the average case of this disease is very striking. The organ itself is enlarged in proportion to the amount of tissue involved. Twice the normal size is probably near the truth, 12 INFECTIOUS DISEASES AMONG POULTRY. although but one was weighed to accurately determine this point. In this case (No. 52) the liver weighed 10.7 ounces. Over the surface of the organ are distributed roundish, discolored spots, distinctly demarcated from the surrounding tissue. These spots vary much in numbers, in size, and in appearance. They may be dis- tributed uniformly over the whole surface of the liver or they may be limited in number to a few. They vary from 3 to 15 mm. (one-eighth to two-thirds inch) in diameter. Inasmuch as a detailed description of the different cases examined is given in the appendix, to which the reader is referred, only a general description will be attempted here. In endeavoring to group these spots according to their general appear- ance we find several types, which, as will be seen below, correspond to different conditions of the diseased tissue. We have in the early most active disease process, spots like those photographed and figured in Pis. I and II. They are sharply defined circular areas of a lemon yellow or an ocher yellow color. A careful scrutiny shows that the spot is not homo- geneous in structure, but made up of a delicate network of yellow, as shown in the plates. This yellow substance represents dead tissue. In another class of spots we have in place of the yellow meshwork an entirely different appearance. The spot is of a mottled brownish color and contrasts only slightly from the surrounding liver tissue by its darker color. It may contain a central yellow nucleus of dead tissue and a narrow outer border of the same character, or the border may be a dark brownish circular line. The entire spot has an indistinct appear- ance and is flattened or even slightly depressed below the surface. Jn some cases the spots assume still another aspect. They are uniformly whitish and shade off somewhat gradually into the surrounding tissue. If sections be made of the affected organ it will be noticed that these surface spots represent masses of liver tissue in the same condition. The spots are simply the places where these disease foci intersect the surface. Some are found deeply embedded in the liver tissue, and therefore not visible on the surface. The lesion of the liver is thus represented by few or many foci of disease having in general a spheri- cal form and appearing on the surface of the organ as round spots (PI. Ill, fig. 1). Occasionally the lesions become more extensive and the death of large portions of liver tissue follows. This is well shown in fig. 2 of PI. Ill, where a large volume of liver tissue is transformed into a yellow cheesy substance. The changes in the liver are most easily explained by assuming that the microparasites are conveyed by the blood directly from the diseased cseca into the liver and there deposited in different places, where they begin to multiply and spread in all directions, thereby forming the spherical foci of disease which appear as circles on the surface of the liver. This theory is borne out by the results of the microscopic exam- ination. SPECIAL CHARACTER OF THE DISEASE. 13 In sections of hardened tissue from the liver in which the disease has but recently begun the affected regions are invaded by large numbers of protozoa, which occupy a kind of reticulum formed probably from the connective tissue stroma. The liver cells have partially or wholly dis- appeared from these foci. The parasites occupy the meshes of the tis- sue either singly or in groups. The reticulum is provided with a small number of nuclei, some of which are closely applied to and curved partly around the parasite. The blood vessels are usually much dilated and filled with red corpuscles. The yellow masses observed with the naked eye in the surface spots in many cases are Shown to be patches of an amorphous substance which takes nuclear stains very feebly, the aniline colors not at all. It may be described as a coarse network in the meshes of which small cells, and very rarely parasites, are seen. This substance I assume to be the result of coagulation necrosis of the liver cells by which they have lost their nuclei and have become fused into a formless mass. I at first was inclined to look upon it as fibrinous in character, but the discovery of transitional stages confirms the view that it is made up of dead liver cells. It is probable that the plugging of blood vessels in the liver by parasites carried from the caecum is tbe cause of the necrosis, since such plugs or thrombi are not uncommon in sectious of the diseased spots. With the appearance of the microparasites reactive changes begin at once which complicate the process. We have at the outset an active multiplication of the microparasites which take the place of the original liver tissue, and a process of coagulation necrosis going on at the same time. Soon multinucleated (or giant) cells appear which not only take in the microparasites but which are also engaged in remov- ing dead tissue. At least their collection in groups around and within the necrotic areas lead us to assume this. Not infrequently they are grouped around what appears to be a plugged vessel, or else they occupy the lumen of the vessel itself. The presence of round or oval vacuoles within these large cells indicates that parasites have been taken up (PI. V, fig. 3). In still older cases the diseased spots are found more or less filled with small round cells which may have passed into the dead regions from the blood vessels. In all cases the latter are more or less enlarged, and they seem to encroach upon the liver tissue, thus filling in part the void produced by the cell death and giving the surface of the liver a brownish mottled appearance wherever the disease spots are. The processes of advancing disease and necrosis or death of tissue on the one hand, of repair on the other, seem to go on side by side, now one now the other predominating. Of the process of repair case 16 is a very good illustration. In this bird the liver tissue was undergoing sclerosis associated with the true healing process, which is referred to more in detail in the appendix. 14 [NFECTIOUS DISEASES AMONG POULTRY. Besides the lesions directly due to the mioroparasites in the cseca and in the liver, there were aochanges observed to indicate thai the parasite was multiplying in other parts of the body. Even where the disease was extending locally from caecum to adjoining intestine, the process was not due to any advance or invasion of the parasites themselves. Regularly recurring changes in other organs duo indirectly to the • lest ruction of liver tissue, and to tho loss of the cava as important aids in the process of absorption were not manifest. The blood of many of the eases was examined before the bird was killed in older to detect any existing blood infection. No disease of tlic blood was observed, however, excepting in No?l(>, in which a pro- nounced leucocytosis was present. In this case the disease was disap- pearing and the liver undergoing sclerosis, as stated above, in a small number of cast's, some diseased, some healthy (Nos. 5, f>, L2, 15, and 33) flagellates were detected in variable numbers. They were evidently not related in any way to the protozoan disease. These bodies (PI. V. figs. 6 and 7) are spindle-shaped and made up of an oval, feebly granular, central body (nucleus) around which the cell body forms two lateral wings and two tapering extremities finely granular in structure. Motion was not detected at the temperature of the sur- rounding air. Higher temperatures were not applied. The nucleus of this flagellate is about 25 n long and (i // broad. The entire organism 15 65 to 70 a long. When the blood is dried in thin films upon cover- glasses and stained, these bodies appear in many instances much broader than in the fresh condition. This would suggest that the organism may be a flattish body rolled up so as to bring the two lat- eral margins near together. The results of the examination of turkeys made thus far indicate that the disease may follow several courses: (1) After a certain period of disease regenerative processes begin which tend toward a permanent recovery. (L*) The disease may proceed so rapidly from the very start that the affected turkeys die early in life. (3) The disease may come to a standstill, but the amount of dead tissue in theea'ca and liver may be so great as to favor the entrance of bacteria which are responsible directly for the death of the bird late in the summer or fall. The direct action ol' the microparasites upon the body seems to lead to a mechanical destruction of tissue. In this respect they differ from most bacteria, which may combine a locally destructive process with a general poisoning ol' the body. The extensive destruction of liver tissue combined with the loss of the use of one or both caeca in the digestive process must of necessity lead eventually to weakness and emaciation. The feebler resistance of the atl'eeted animals was brought to our notice last summer by their speedy death after a long ride or a few days oi' confinement. THE MICROORGANISM. 15 As regards the spontaneous cure of infected birds we may regard i as probable that only those in which the disease comes to a standstill before it has made much headway are likely to recover. In those in which much destruction of tissue has taken place complete recovery is impossible. The dead masses embedded in the caeca or the liver, or both, form a nidus for bacteria of certain kinds. These penetrate into the pleuroperitoueal cavity and there set up inflammation and finally lead to a general septic infection of the body. The immediate effect of the disease may thus be very slight at the outset and the symptoms develop slowly. The great increase in the size of the liver indicates a certain amount of compensation for those portions which have been destroyed. The effect of the disease on the flesh of turkeys killed in the early stages is not recognizable. In a few cases which died from a severe form of the disease the flesh had a mahogany color, probably due to retained biliary substances. THE MICROORGANISM. (Amaba meleagridis n. #p. 1S95.) In the 18 cases of this disease which came under observation either the liver or the ca^ca, or both organs, were examined microscopically in 14. In these organs certain microorganisms were detected in all but one case and associated directly with the peculiar disease process already described. In those cases in which the disease was recent, or at its height, the parasites were very numerous in the affected tissues, while in those; in which the disease process was far advanced, and associated with degenerative or regenerative changes, the parasites were found with difficulty. These facts are summarized in the follow- ing table: 16 INFECTIOUS DISEASES AMONG POULTRY. cc- fcJO co p CS t: CD CD 0. co X 3 C OS >tt -5 >5 d X X o *S CD SB X X c * n c ■s - c ^ o p B o X d c c d fco * p | CD - O p -e R a X p X P P > T P M c F? < £ e >d 13 cc a X X *4 s r c = _g CD c > X c 1 .2 i 1 - i - a _a s a CD c- S. CD £ 1 X ti ■- CD c a - — c c o CD x B c X s B i « c a 2 -S C c CD C - 1 X p. r X ■r -c X o CD ^ O — ~z t: CO ft V «: < fc fc 8 fc " B <■ fe o a a o e o CD C X B - X TS B X B a 4-: C ' = c ■- £ B a ■" £ CD X e 1 = X c c cc cc B X X ■- - X ac o - c X 6 X X t- I V. X i C! X 0! c c c c a X ■f. X c c «! ^ ^ < !z < t>-^ V X> -t- ~ CD 4 CD , X X & . X X — CO O cS > '5 a - D ; ^ 'a X s > 1 'S i a. 2 p c fc c •: p c c p p o c c t a a -c 4 s •s J t> ? CI - (- g >: X -3 -C F£ F£ > P % H CD cS cu CO 3 c- x I x g a X \ * St c £ c c f- X X a x Z *c1 a S £ X ft X ft O X 8 x ft a a * *z c X X X X a XI x> « c c P C c a E X *- p 8 o =44 o A c - C c ^ B c : o .c c 4^> a a cc & X - X a P> > X > c X X -M 4- a o CO cr EC "5 - '5 cc) c: '5 A B p _c c p fe c c (■ B : t4 !- c p ^ *= a a 1 fC a — 4 X — ^ ■i t; i ^s fA +: - Eao t- !» k k : K c V O C £ 1* F* p ? fS < £ 3 ^ £ M 6 rd _B C3 |c 9 rp X ■73 X - O SB !-. B ; CD a T „ „' : c c FC « >c .- c : c: © c8 n - ^ _a ; ^ r3 ^ 12 3 : c a ; .2 1 p ^ C P p ^ »-i p ^ P ^ a re c 1 1- 1 X c c c- O n ft s c 1 3 - C f < P p £ 4 h £ 12 a ^ £ z c s "- a t - C5 t- a P: ft ^ F« F= F^ ^ F^ ft ^ F^ (i ^ CD A ^ | » CO 2 a . a 1 CI > c c a c ft ■> J ,£ a ) o c > : > o o c - c c 1! if c i 'r 1 ■s P 6 | CO rp 1 p (C o T3 ft < £ > + 1 £ I i i E ! : 2 « cc r- CV c & c i c CY i cv CM cv If ■s&f" < C^ c > ■* t If cc > ex o T cr c i c CC 1* IT C CM c CN CO o- c If in o-« fe 4i I THE MICROORGANISM, 17 In the examination of the parasite within the tissues minute particles of the latter were crushed in iodized amniotic fluid or in normal salt solution. Sections were also made. Unfortunately, a freezing micro- tome was not at hand, nor any warm stage for determining- the effect of higher temperatures on these bodies. The most frequent appearance presented by the parasites under these circumstances was that of round homogeneous bodies with a sharply defined, single contoured outline (PI. V, fig. 1). Their appearance sug- gests that of the myelin bodies found in the cells of the pulmonary alveoli, not refrangent enough to represent oil globules, but too homo- geneous to represent the ordinary protoplasm. Within these bodies and situated somewhat eccentrically is a group of very minute granules, probably representing a nuclear structure. These forms were encoun- tered in those cases in which the parasites were found most abundant in sections of hardened material (Nos. 5, 24, 26) ; also in one case in which repair was evidently going ou (No. 16). They vary somewhat in size. In Nos. 5 and 16 those that were measured were 8 to 10 /z in diameter. In No. 26 they were 12 to 11 /< in diameter. In No. 34 some of the bodies were oval, having diameters of 12 and 15 /<, respectively. They are thus distinctly larger than the parasites within the tissues, which have undergone the hardening process. The latter are from 6 to 10 j.i in diameter. This difference may be due to shrinkage, on the one hand, and on the other to a slight flattening of the bodies by pressure in the fresh preparations. These peculiar homogeneous bodies were found, as a rule, free in the crushed preparations, although occasionally giant cells were detected which contained a number of them. The cell nuclei of the giant cell were not visible in the fresh condition. Numer- ous coarse granules were embedded in its protoplasm, less frequently fat globules. Besides the homogeneous bodies, organisms of nearly the same size but with uniformly granular protoplasm were also found, chiefly within giant cells. These were not infrequently broken and rims or fragments of protoplasm were left attached to the parasite (PI. V, fig. 2). For the study of hardened material the tissues were removed in most cases immediately after the bird had been killed, and placed in one or more of the following fixing and hardening agents: 95 per cent alcohol, saturated solution of corrosive sublimate, Foa's solution (equal volumes of the preceding solution and a 5 per cent solution of bichromate of potash), Flemming's solution (undiluted). The tissues were fixed in the three last mentioned during one day, then washed in running water during another day and treated with ascending strengths of alcohol, according to the usually prescribed rules. The tissues were then passed through absolute alcohol and chloroform, infiltrated in paraffin, and the sections cut dry. Various staining reagents were employed, including Delafield's hematoxylin and eosin, alum carmine, Biondi's triple stain, saffranin, Gram and (Iram-Weigert's. stain. Of the fixing and hard- 17897— No. 8- 2 18 INFECTIOUS DISEASES AMONG POULTRY. ening agents I am unable to consider any one as superior to tue other in bringing out the parasites in the tissues when subsequently stained. By this I do not mean to infer that there was no preference when their action upon the tissues is considered, for here they mani- fested their respective peculiarities already well known. But the fact remains that now the one, now the other, tissue demonstrated the para- sites best. In general, hardening in corrosive sublimate and alcohol and staining in Delafield's hematoxylin and in eosin proved the most suc- cessful. The bodies were, however, brought out with other dyes, such as methylene-blue, with variable distinctness. The microparasites as found in sections of hardened tissue are spher- ical or slightly oval bodies from G to 10 fx in diameter. In sections stained with hematoxylin and eosin they have a homogeneous bluish- red tint, feebler than that of the tissue nuclei of the host. They are, however, distinctly seen, and the advantage of a more intense stain is questionable. In most of these bodies a minute, distinctly blue ring is seen situated centrally or somewhat eccentrically and representing the nucleus. This is about 2 // in diameter. With high powers a very minute (nucleolar?) point may be seen in some parasites within the nucleus. Other differentiations of structure were not noticed. The presence within the connective tissue spaces of parasites in groups of two or more individuals, as well as of single individuals, makes it highly probable that at least in the early stages of the disease there is active multiplication of these bodies. This appears to go on as a simple process of division, if we are to judge from the grouping within the tissues. The variation in the number of individuals com- posing such groups, as well as the absence of any common membrane inclosing each group, indicate at least that the multiplication is not an endogenous segmentation such as belongs to the sporozoa. This brings us to a consideration of the nature of these protozoa. Their simple structure would lead us to class them with the amoebae, of which one form is now known to produce a similar disease in the human subject (amoebic dysentery). Amoebae are also not uncommon inhabit- ants of the large intestine of man and certain animals. The peculiar homogeneous structure and rigid outline of the organisms before us as they appear when examined in tissues directly from recently killed animals may represent a kind of encystment in the presence of the adverse forces of the animal tissues. In the sharply defined vacuoles within the giant cells this rigid form seems to have left a permanent impression (PI. V, fig. 3). The relation which the parasite bears to the microparasites found in external tumors or warts (Molluscum contagiosum) of fowls, or to those flagellates which are associated with diphtheria in fowls, or finally to the diphtheria referred to in text-books as due to gregarinosis may be a very distant one. Yet, in the present state of our information con- cerning these parasites, it is worth while to be on our guard before THE MICROORGANISM. 19 making positive assertions, and leave it to future work to decide if any relationship exists. 1 We are naturally led, in a consideration of this microorganism, to inquire what relation it bears to the tissue cells of the host. Is it an intracellular parasite during- any portion of its parasitic existence? The evidence brought forward here would lead me to state that it lives in the interstices and lymph spaces of the tissue, but not within cells. This seems certainly true of the caecum. In the liver the liver cells seem to become necrotic or else, disappear so rapidly that it is impos- sible to determine just where the parasites begin to multiply. They do not live within the blood vessels, as they are not found within them excepting perhaps in a thrombosed vessel. They must, therefore, occupy the place of the liver cells. It is probable that they begin to multiply in the connective tissue adjoining the bloodvessel, and simply crowd out the liver cells, leaving the connective tissue stroma of the lobules in whose meshes they are found. Their presence within giant cells i-s seen in almost every infected organ subject to examination. In teased preparations of the fresh tis- sues they are frequently found with remnants of the inclosing cells still attached. This intracellular condition is, however, a purely pas- sive one so far as the parasite is concerned. The fate of the microparasite within the tissues of the host seems to tend toward destruction. Both the death of the tissue itself and the repair seem to lead to the disappearance of the parasites. In most cases there may be seen in the same section a partial dissolution of some of the bodies, while others are still in good preservation. Evi- dently their life within the tissues is not very long. The attack upon them by large giant cells in the later stages of the disease has already been mentioned. A discharge of the mieroparasites which escape destruction probably takes place from the walls of the caecum, when these break down, into the contents, in which they are carried outward. A similar discharge may take place from the liver through the bile ducts into the intestine. Another way of dissemination would be in the death of the diseased turkey and the dissolution of its body whereby the organisms are set free. Speculations in this direction are, however, of little value until experiment shall have determined whether turkeys are infected directly from sick turkeys, from healthy, immune or recovered turkeys, in whose ca-ca the parasite may perhaps vegetate indefinitely, or from some external source. The close analogy existing between this disease and that of amcpbic dysentery in the human being deserves at least a brief statement in these pages. The occurrence of amoebae in intestinal affections of man was noticed as far back as 1875 by Losch. Since that date it has been 1 The presence of numerous flagellates in the caeca of healthy turkeys has already been poiuted out ou page 9. 20 INFECTIOUS DISEASES AMONG POULTRY. the subject of many investigations. 1 Two of the more exhaustive investigations which have appeared are those of Councilman and Lafleur 2 and of Kruse and Pasquale. 3 The points of analogy between the avian and the human disease are that in both there is an affection of the intestine (large intestine in man, cneca in turkeys) associated with liver disease due to aincebse. The intestinal wall in amoebic dysentery is greatly thickened, owing to an (edematous condition. It is also thickened in circumscribed areas and contains cavities filled with gelatinous-looking pus. The amoebae vary much in size and contain vacuoles. They are found in variable numbers in the bottom of the ulceus and in the discharges. The large numbers of amoeba* found in the intestinal contents led Coun- cilman and Lafleur to infer an active multiplication therein. The pres- ence of the parasites within the submucosa is described by these authors in one case 4 only. In the turkey we have seen that the parasites are always present in the connective tissue spaces of the mucous and submucous membrane. Their presence in the contents of the crccuin is highly probable from examinations made last summer but not definitely settled, as it is diffi- cult to recognize the parasites in the feces. The microparasite of the turkey disease differs from the Amoeba dysenteries in being quite uniform in its appearance, varying but slightly in size (from 6 to 10 // in diameter) and in being free from vacuoles. Movements characterized as amoeboid have not yet been demonstrated. The liver affection in man appears usually as an abscess. In turkeys it appears as a variable number of foci in which the microparasites may be present in great abundance. The difference in the nature of the lesions must be largely attributed to the different reaction of the tis- sues of birds toward injuries. This brief statement must suffice to point out the analogy between the human and the avian disease, and the tracing of any further relationships must be left to those specially interested in this subject. Before concluding the discussion of the microparasite of this disease I desire to refer briefly to peculiar organisms found in the lumen of the tubules of the creca. Fig. 5 of PI. V depicts these bodies very well. The figure represents a cross section of one of the tubules from the diseased csecuin of No. 26. It will be noticed that the tube is packed with minute organisms of a roundish or oval outline provided with a more deeply stained body, probably a nucleus. The organisms, after 1 For a good resume", with citations of the literature, the interested reader is referred to Schuberg: Centralblatt fiir Bakteriologie, XIII (1893), Nos. 18 to 22 inclusive. 2 W. T. Councilman and II. A. Lafleur. Amoebic Dysentery. The Johns Hopkins Hospital Reports, II (1890-91), pp. 395-548. 3 W. Kruse u. A. Pasquale, Untersuchungen iiber Dysenterie und Leberabscess, Zeitschrift f. Hygiene, XVI (1894), pp. 1-149, •»Loc, cit., p. 490, RELATION OF BACTERIA TO THE DISEASE. 21 being fixed in corrosive sublimate and hardened in alcohol, measure from 4 to 5 /.i in diameter. The nuclear body, though it appears round or oval in the figure, is actually more complex in form. Careful focus- ing with a high power (x 1,000) shows a spindle-shaped or oval body which may be bent like the arc of a circle. Its shortest diameter is about 1 //. At first I was inclined to look upon these bodies as blood corpuscles which had escaped into the tubules during the disease process from the cavity of the caecum. This view is made very improb- able by a number of facts. The red corpuscles in the capillaries of the same section are quite different from these bodies, both as regards the color of the hemoglobin, and the form, size, and structural appearance of the nucleus. These problematical objects assume a bluish-pink color when stained in hematoxylin, and the nucleus stains quite deeply and solidly. Again, it would be difficult to understand why all the tubules should become packed with these bodies if they were blood corpuscles. Another supposition, that they might be some stage of the microparasite of this disease does not harmonize with the fact that they are found within the tubules of the healthy c;ecum (No. 47). They may be absent in cases where the disease is most active (No. 3). On the other hand, they were very abundant in No. 20, and less so in No. 10. The most satisfactory assumption is that these organisms represent one of the unicellular animals, probably a flagellate. It is interesting to note that flagellates were found in large numbers in the fresh con- tents of the crecuin of No. 47, in which these bodies were found within the tubules in sections of hardened tissue. There is probably no genetic relation between this hypothetical organism and the true parasite of the disease under consideration. The latter is larger, its nucleus is smaller and simpler in form, and its behavior toward staining reagents is different both as regards the cell body and the nucleus. It would seem, on the whole, that we have here a microorganism which inhabits the caecum and by preference the depths of the tubules. Its effect upon the health of the turkey can, of course, be only conjectured at present. THE RELATION OF BACTERIA TO THE DISEASE. From what has been stated concerning the presence of the protozoan parasite in the diseased tissues, there can be little doubt that they must be regarded as the cause of the disease. In the course of the investigations the possible bearing of bacteria upon the disease was not entirely overlooked and cultures mainly upon agar were made from the blood and the liver of a considerable percentage of the infected turkeys. Usually, bits of liver tissue were transferred to the culture tubes. Of the heart's blood, one or two loops were inoculated. The results obtained varied from case to case. As a general rule, tubes inoculated from birds that had just been killed remained free from growth, whereas the cultures of those which had died during the night 22 INFECTIOUS DISEASES AMONG POULTRY. and were examined next morning were quite regularly fertile. The bacteria isolated from these cultures were examined by Dr. C. F. Daw- son, assistant in the laboratory, and most of them found to be B. coli communis. Several of these were afterward reexamined by me and his results confirmed. The absence of any uniformity in the bacteriological results as well as the appearance of B. coli in the organs of dead turkeys indicates that pathogenic bacteria were not associated with the protozoa in the cases examined. It furthermore warns us to be careful not to attribute to such bacteria as may be found the power of producing disease, as has been lately done by Lignieres, * who found B. coli in the organs of a small number of dead fowls and claimed, without positive proof, that they were the cause of a septicaemia. THE RELATION OF THIS DISEASE TO CERTAIN OTHER DISEASES OF POULTRY. (1) To other diseases of the cceca in turJceys. — In the investigations made in Rhode Island three cases came under my observation which make it certain that not all diseases affecting the caeca of turkeys are due to the protozoa described. Of one case (No. 7) only the intestines were obtained. One of the attached caeca was greatly distended by an exudate, similar to that found in some cases of the protozoan disease. At about 1 inch from the blind end the caecum abruptly swelled out to a diameter of 1^ inch. The enlarged portion was about 2 inches long and very firm to the touch. The whole mass was placed unopened in alcohol. When it was subsequently opened the enlargement was found due to a firm exudate with a narrow canal passing through the center. The exudate readily peeled away from the wall, which was bat slightly thickened. The second case (No. 2.1) was similar to this. Only one of the caeca was affected. The notes on this case are as follows: One caecum slightly distended by a rather firm cylindrical mass of feces encased in a Avhitish leathery exudate made up of concentric layers. The whole is not adher- ent to the mucosa. This membrane is dull, slightly congested. The wall is very slightly thickened. The liver is free from disease. In the intestines are numerous tapeworms. Two cultures were made by placing bits of liver tissue in tubes of inclined agar. In both, colonies appeared. These were subsequently found to be closely related to B. coli communis. In the third case (No. 41) both creca were diseased, the liver normal. One caecum was very much distended over a distance 3 inches long, attaining a diameter of three-fourths of an inch. From the serous aspect the wall appeared very hyperaunic. When the tube was slit open the distension was found due to a cylin- drical mass of exudate, very firm, yellowish white. The exudate appears deposited in concentric layers. The lumen of the tube within this exudate was almost occluded. Odor strongly fecal. The exudate easily peeled away from the wall in a single mass. The wall was smooth and hyperaemic and but slightly thickened. 1 Septicajmie a coli bacille chez la poule. Compt. rend. Soc. Biol. 1894, p. 135. RELATION TO OTHER POULTRY DISEASES. 23 This exudate was hardened in alcohol aud transverse sections cut from it. These show that it is composed almost exclusively of a meslnvork of amorphous material, probably fibrin. Cell groups were found in but one locality of the exudate. The other crecum is only slightly distended. It contains a mass of exudate about 1 inch long and one-third of an inch in diameter lying loose in the cavity. The mucosa is roughened and covered with a thin slough or exudate. Sections of the wall of this caecum show the mucous membrane replaced by a layer of young connective tissue cells in which tubules are absent excepting in cir- cumscribed regions in which the remnants of the tubules are still recognizable in the amorphous mass adhering to the submucosa. The muscular coats are not penetrated by cell masses, but the vessels of these and the subserous membrane are greatly distended with corpuscles. The small intestine of this turkey contained numerous small tapeworms. Two agar cultures were made from heart's blood and one with a particle of liver tissue. In one of the blood cultures a number of similar colonies developed. The bacilli composing one of them had all the cultural characters of B. coli communis. These three cases are of interest as indicating the existence of some other agency, probably bacterial in nature, which affects the cteca of turkeys. It differs from the protozoan disease in the entire absence of any liver affection and in the absence of any marked thickening- of the walls of the c<£ca. The exudate is much more abundant and obstruct- ive than in the protozoan disease. Further investigations are neces- sary to define more clearly the nature of this affection and its cause. A similar affection of the cwca was found in two turkeys by Von Eatz in Budapest. 1 He found much thick mucus in the mouth and esophagus. The mucous membrane of the small intestine was studded with hemorrhages aud small, removable pseudo- membranes as large as lentils. Both ceca of one turkey contained a partly dried, cylindrical mass, and many minute worms 8 to 14 mm. long. In one caecum of the other turkey the same dry, cylindrical mass, easily removable. The mucous mem- brane itself was covered with layers of pseudomembrane. The other caecum was distended with gases and a grayish, semirluid mass. Both contained many round- worms. The author does not hesitate to attribute the crecal disease to the roundworms. This conclusion is, however, merely an inference based on the presence of worms aud exudate. It is more than probable that the disease is bacterial and secondary to the catarrhal affection of the mouth. (2) To disease of the ccvca in fowls. — This is by no means uncommon. Ziirn 2 considers it a form of diphtheria which may affect the various parts of the head, the digestive and respiratory organs. He states that the disease of the caecum may appear as an independent affection in water fowls and turkeys. The disease is accompanied with great depression aud weakness. The diarrhea which appears is at first semi- fluid and mucous, later it becomes fluid and is mixed with blood. The foul- smelling discharges may be followed by constipation, and then the 1 Blinddarmentziindungen bei Truthiihnern (lurch Ascariden veruraacht. Deutsche Zeitschrift f. Thiermed., XX (1893), p. 74. 2 Deutsche Zeitschrift f. Thiermed., X (1883), p. 189. 24 INFECTIOUS DISEASES AMONG POULTRY. caeca and the rectum are found after death filled with yellow croupous masses in layers upon the frequently ulcerated mucous membrane- The disease lasts fourteen to twenty days or even two to three months. Often a relapse follows an apparent cure. He states that it frequently happens that the croupous or diphtheritic affection of the throat, nose? and eyes appears healed, when suddenly the intestinal disease breaks out and usually ends fatally. The writer has seen two instances of disease of the caecum in fowls. In one case one csecum had its walls very much thickened. The same was true of the second case. In this the thickening- was due to a reparative inflammation following" the loss of a greater part of the mucous membrane. In sections of hardened tissue protozoa were not recognized. It is probable that in this .fowl the disease was secondary to a dipththeritic affection of the head. Siedamgrotzki ' describes a disease of both creca in a hen. They were very much enlarged. In one caecum the wall was thickened by inflammation, but the mucous membrane was intact. In the other the wall was also thickened and adherent to neighboring organs. The mucosa was covered with a yellowish-brown, thin, pseudomembrane. Disease of the caeca in poultry seems to be a widely distributed affection, both primary and secondary to other diseases, and evidently due to more than one agency. It is to be hoped that more will be known concerning these affections in the near future, and that the demonstra- tion of one specific cause in the form of protozoa will pave the way for the determination of the others. GENERAL CONCLUSIONS. In the preceding pages we have shown that there prevails a disease of turkeys which attacks the young by preference, which runs no reg- ular course, but varies from bird to bird in severity, duration, and termination. It begins in the creca and thence invades the liver through the blood. Though restricted to these two organs, its action is severe enough to prove fatal to many affected turkeys. We have seen that the disease process is always associated with a protozoan parasite of very minute size, whose destructive action is due in the main to its powers of rapid multiplication within the tissues. It is probably discharged with the droppings of the diseased birds. These are the main facts learned by the brief investigations of last summer. While we may make certain conjectures as to the modes of transmis- sion of the infectious agent based on these investigations, we are at present unable to go further than this until experiments have been car- ried forward in other directions. From our present standpoint I think it safe to assume that the micro- parasite is transmitted from bird to bird without passing through 'Bericht ii. d. Veteriuiirwesen im Kouigreich Sachsen, 1872, p. 84. CONCLUSIONS. 25 any intermediate host. The microparasite, discharged perhaps in an encysted stage from the sick bird, is taken up with the food and water by others and sets up disease directly. If the parasites were taken up with insects, for example, we should expect to find the disease diffused through all Hocks. But even the lim- ited experience of last summer leads me to believe that certain flocks only are infected and that by uninterrupted transmission the disease becomes perpetuated and diffused among- neighboring flocks. The perpetuation of the parasites I am inclined to think is to be sought for in the older turkeys, which carry them in their body, most likely in the digestive tract during the winter. This view is supported by the fact that turkeys not infrequently recover from the disease. This re- covery does not mean, however, the destruction of the parasite within the body, for we have now information concerning the persistence of a variety of parasites — bacteria and protozoa — within the body long after recovery. The evidence which I have presented in this report seems to show that the turkey is iufected early in life and that infection does not take place later on. If this be so, the transmission from the old to the young- is easily understood. If the susceptibility to infection remained for any length of time we should expect to find the two caeca infected in every case. But in 7 out of 18 cases only one caecum was found diseased, the other normal. It is true that other explanations of this condition referable to acquired immunity, might be given, but the one cited seems to be the most acceptable. If the theory that the disease is transmitted more or less directly from old to young should prove to be true, the remedy for such a state of affairs would appear to lie in two directions: (1) The disease might be allowed to go on and some remedy found which will check it and lead to a cure; or (2) The diseased flocks might be entirely destroyed and new birds obtained elsewhere, after a thorough cleansing and disinfection of the territory formerly occupied by the flocks. The latter alternative, though very heroic and severe at first, seems to me the best in the end, especially as we might search in vain for a remedy which will check the disease in the young. Anticipating the investigations somewhat in this direction, I had hoped to determine the distribution of this disease in the country at large by an appeal for the shipment to this Department of diseased turkeys or organs there- from. Up to the present no material has been received, so that the study of distribution has made no progress. 1 It is evident that if the disease must be weeded out by a destruction of whole flocks it is highly important to find some locality free from such disease from whence new stock may be obtained. To obtain such information is by no means an ir rhe casca of about 30 turkeys from the Washington markets were examined during February of 1895, and found free from disease. 26 INFECTIOUS DISEASES AMONG POULTRY. easy task, and may be made still more difficult by the infusion of a certain amount of local pride and self-interest. The disease is, how- ever, readily recognized in most cases, so that anyone who has examined the plates of this article and read certain portions of the text may be able to detect it. The peculiar circular spots on the liver, coupled in later stages of the disease with the presence of yellowish cheesy masses or whitish scars in this organ, are very characteristic and probably peculiar to this affection. Disease of the caeca, unless accompanied with the spots on the liver, should not for the present be regarded as belong- ing to this affection. When we come to the subject of treatment some difficulties arise. Though turkeys may appear drooping, unable to keep up with the move- ments of the flock, and even have diarrhea, the precise nature of the disease is not made clear by these symptoms. Among the 50 turkeys examined many were taken alive as suspicious cases. When killed the protozoan disease was not found. They were suffering from a variety of other affections, the causes of which, mentioned in the order of fre- quency, were lice, tapeworms, gapeworms, ticks, injury, and a diphthe- ritic disease of the caeca likely to be mistaken for the genuine protozoan disease. The same treatment applied to such a variety of disorders can hardly be looked upon very hopefully. Still, the subject merits attention. The success which quinine has had in combating malaria leads me to suggest its use to those who are in a position to experiment with this disease. Since the microparasites are embedded in the walls of the ca'ca and in the liver the remedy to be tried must do more than act locally in the intestines. It must act upon the parasites through the blood, and its effect on the diseased turkey should be carefully watched to note any poisonous action. The disinfection of the coops and other structures designed to give shelter to turkeys, and other poultry as well, should be carried on as for bacterial diseases until further investigations shall have been made. The following disinfectants are strong enough to kill spores of bacteria, and will probably destroy the various stages of the protozoa: (a) Corrosive sublimate (mercuric chloride), 1 ounce in about S gallons of water (one-tenth of 1 per cent). The water should be put into wooden tubs or barrels and the powdered sublimate added to it. The whole must be allowed to stand for twenty-four hours, so as to give the subli- mate an opportunity to become entirely dissolved. Since this solution is poisonous, it should be kept covered up and well guarded. It may be applied with a broom or mop, and used freely on all woodwork. Since it loses its virtue in proportion to the amount of dirt present, all manure and other dirt should be first removed before applying the disinfectant. The manure should be covered with lime. (b) Chloride of lime, 5 ounces to a gallon of water (I per cent). This should be applied in the same way. APPENDIX. 27 (c) The following disinfectant is very serviceable. It is not poisonous, but quite corrosive, and care should be taken to protect the eyes and hands from accidental splashing: Gallon. Crude carbolic acid i Crude sulphuric acid ! These two substances should be mixed in tubs or glass vessels. The sulphuric acid is very slowly added to the carbolic acid. During the mixing a large amount of heat is developed. The disinfecting power of the mixture is heightened if the amount of heat is kept down by placing the tub or glass demijohn containing the carbolic acid in cold water wjhile the sulphuric acid is being added. The resulting mixture is added to water in the ratio of 1 to _!0. One gallon of mixed acids will thus furnish 20 gallons of a strong disinfecting solution, having a slightly milky appearance. (d) Ordinary slaked lime, though it does not possess the disinfecting power of the substances given above, is nevertheless very useful, and should be used more particularly on infected soil. APPENDIX. In the following pages is given the history of the turkeys which have been examined up to the time of the completion of this bulletin. It was thought best to include the brief notes of those turkeys affected with maladies other than those of the infectious disease under consideration, to illustrate the existence of such affections and the necessity for fur- ther investigations. Turkey No. 1. — Portions of the liver, caeca, and lungs received in weak alcohol about the middle of October, 1893, from Mr. Cushman. Age of fowl not known. Lungs dark, congested. The wall of the caecum is fully 5 mm. thick. In the liver are disseminated firm yellowish masses simulating the cheesy matter in tuberculosis. Tissues not in very good condition for microscopic examination. They were, how- ever, placed in absolute alcohol and subsequently cut in paraffin. Sections of lung tissue show all vessels densely packed with red corpuscles. No other changes. Sections of the thickened wall of caecum stained iu alum carmine, hematoxylin, and eosin, methyl violet, according to Cram, and in Weigert's fibrin stain. The hematoxylin proved to lie the best. The thickening of the wall is due in the main to cell infiltration of the submucous tissue. The entire mucous membrane is sloughed away, and the submucosa presents a ragged appearance along the exposed border. Throughout the section, and more particularly near the serous aspect, there are many distended capillaries filled with blood corpuscles. The nature of the cellular infiltration not recognizable, owing to imperfect hardening. In certain areas there may be seen, however, a peculiar col- lection of cells having several nuclei and inclosing large vacuole-like spaces. These spaces were subsequently recognized as having been occupied by protozoa. These phagocytes, with several nuclei shaded oft" into exceedingly large giant cells, over 80 j.L in diameter, often forming large patches by collecting into groups. They are quite uniformly dotted with nuclei, and contain relatively very few parasites. Sections of liver tissue showed an extensive substitution of the parenchyma by numerous and greatly dilated blood vessels within newly formed connective tissue. 28 INFECTIOUS DISEASES AMONG POULTRY. In such areas only a few islands of liver cells are recognizable. Parasites not seen. Giant cells rare. Turkey No, ;'.'. — Liver and a portion of the intestine, with cseca attached, sent by Mr. Cu8bman from Rhode Island on April 2, 1891, and received April 5. Turkey probably a large one. Post-mortem changes well under way when organs were received. It was, how- ever, not difficult to recognize the disease. Only one ca-uui affected. About one- half of the tube, beginning with the blind end, is almost completely occluded with a firm, pale-yellowish exudate having the appearance of concentric layers when -cut across, like the rings of a tree. The occlusion is complete at the blind end. The tube, usually only 0.5 to 1 cm. (two-fifths inch) across, is distended to 2 cm. (four-fifths inch). The exudate is firmly attached to the greatly thickened walls. Sections <>f hardened tissue show that the entire wall of the caecum, or what is left of it, is densely infiltrated with round cells. The lesions characteristic of the earlier stage of parasitic invasion no longer recognizable. The liver is beset with a considerable number of circular, slightly depressed areas, which have a pale, mottled appearance. They vary in diameter from 5 to 10 mm. (one-fifth to two-fifths inch). When incised the same appearance is presented within the liver tissue, showing that these circular spots simply represent the surface of roundish masses of tissue which have undergone the same change. In sections of hardened tissue each disease focus is shown to be the scene of a com- plex process of destruction. The periphery consists of normal liver tissue, the capil- laries of which are distended, and gorged with red corpuscles. Within the diseased focus there is disseminated a peculiar meshwork of amorphous, homogeneous matter which stains but feebly in hematoxylin. Its meshes are large enough to hold one or more tissue cells. In some places it resembles more closely mammalian fibrin in its appearance. Liver cells are either entirely absent or present in isolated numbers where this substance appears. Besides this there are areas of considerable cell infil- tration and, scattered about without regularity, giant cells. Parasites are present, but in small numbers. From the liver bits of tissue were placed in three agar and three gelatine tubes. At the same time bits were placed under the skin of a rabbit and a guinea pig. The cultures remained sterile and the animals well. Turkey Xo. 3. — Small specimen ; probably 3 or 4 weeks old. Died in the morning of June 6, 1894, on a farm in Berkshire County, Mass. Examined several hours after death. Weather quite cold. In this case both ca>ca and the liver were involved. In the former the walls were considerably thickened, but there was no exudate within the tube and the mucous membrane appeared intact. In sections of the caeca hardened in alcohol and in corrosive sublimate the wall was found of variable thickness. In some regions it was nearly normal on one side and considerably enlarged on the opposite side. In others the entire cross section was uniformly thickened. The mucosa is still in position and but slightly altered. The cells of the crypts show extensive mucous metamorphosis. The enlargement of the wall is due mainly to an extensive infiltration of the submucosa and of thecircular band of muscular fibers with the protozoa. The muscular fibers are pushed apart into strands, or else entirely obliterated. . These microparasites are found throughout the entrre section in uniform abundance. They are comparatively rare in the reticular tissue of the mucosa between the crypts. In the fresh contents of the ca>ca were found coccidia with distinctly double-contoured Avail. The long axis measured 15 to 20 //, the short 10 to 13 /.i. The liver of this bird was dotted with about a dozen circular spots, A'arying in size, some 7 mm. in diameter. These spots consist in the main of minute yellowish lines embedded in the liver tissue and loosely interlacing to form a circular wheel- like area. They thus differ from some other cases to be recorded in less destruction of liver tissue within the circular area, for the yellowish lines represent necrosis of liver tissue. APPENDIX. 29 In sections of liver hardened in corrosive sublimate and alcohol the foci of disease no longer contained any liver tissue. This is replaced by numerous microparasites surrounded and enveloped in a meshwork of reticulated tissue rich in nuclei. Giant cells are present in moderate numbers. At the time this young turkey died two others were found dead and were exam- ined. Neither was affected with this disease. Turkey Xo. 4. — Has beeu dead for two days. Decomposition well under way. Obtained from a dealer. Extensive spotted disease of the liver and thickening of walls of ca'ca with exudation into the tube. Turkey Xo. 5 (Farm A). — Probably 8 to 9 weeks old. Received alive August 3. Blood from vein of the skin examined. A few fusiform flagellates seen. Nothing abnormal with the corpuscles. Killed. On the neck a small tick. Mouth, trachea, and luugs normal. The digestive tract normal with exception of the duodenum and the caeca described below. The former shows marked pigmentation in points and strhe (villi 1 ). In the rectum and cloaca contents pale-yellow, liquid, containing urate spheres in abundance and numerous flagellates. Both c;eca are diseased. They are unusually short, only one-half the length as usually found in turkeys of the same age (PI. I, fig. 2). Both are distended from one- half to three-fourths of an inch in diameter, and very firm, as if filled up. Vessels on the serous surface injected. The condition of one of them is shown in PI. II, tig. 2. The caecum is slit open longitudinally, and the cut surface exposed to view. The lower two-thirds of the tube is completely occluded by a firm exudate. On the cut surface the wall of the CSBCum is shown as an irregular line, indicating marked thickening along the whole length of the tube. The exudate is pale yellowish- white in color, excepting below, where it is largely made up of a blood clot. The main mass contains centrally an irregular cavity. Above, the tube is filled with small round stones, probably dis- charged from the gizzard. The other caecum has its wall very much thickened, as shown in PI. II, fig. 3. The exudate is also present, but not attached to the walls in the alcoholic preparation. The liver, which is enlarged slightly, is spotted on all surfaces with isolated and continent areas of a circular outline and pale yellow in color. They rarely exceed 4 mm. (one-sixth inch) in diameter. On closer scrutiny the yellowish color is seen to appear as a network. These disks correspond to masses of diseased tissue within the substance of the liver. In crushed, fresh tissue are found isolated and agglomerated bodies of a round form, with a homogeneous colorless disk and a single-contoured outline (PI. V, fig. 1). Near the center of these bodies is seen a small mass of very hue refrangeut granules. They are 8 to 10 fi in diameter. One per cent acetic acid will not affect their appearance. Three cultures on inclined agar were made with a large aud two small bits of liver tissue and a large bit of spleen tissue (about the size of a pea). Furthermore, tubes were inoculated with a loop of blood and with a loop driven into the liver tissue. The six tubes remained free from growth. Turkey Xo. 6 (Farm B). — Selected because of slightly reduced condition. Cooped for two days. Found dead August 5. In abdomen some blood-stained serum. Considerable kyperamia of serous cover- ing of gizzard and of mesenteries. The blind ends of caeca knotted inextricably together, enveloped in a mass of yellow exudate, and attached by means of it to neighboring coils of the intestine and to the abdominal wall. The latter is infil- trated and discolored at this point. After some dissection it was found that only one caecum was primarily diseased. This was filled with an exudate at the blind end for a distance of three-fourths of an inch. The liver is somewhat enlarged, and on its surface are a small number of pale yellowish areas fully one-half of an inch in diameter. They correspond to masses of similarly affected tissue in the liver. < 30 INFECTIOUS DISEASES AMONG POULTRY. J Sections of liver tissue hardened in alcohol were made through these large pale spots. Iu these only small fragments of recognizable liver tissue were found inter- spersed in the diseased focus. Much of this was occupied by a meshwork represent- ing necrosed liver cells fused together. Small necrotic foci were also detected outside of the main focus, embedded iu still unchanged tissue. The necrotic meshwork is arranged in spots generally connected, the interspaces being filled up with groups of minute cells and occasional patches of microparasites. Giant cells are common, usually within or on the circumference of the necrotic areas. The microparasites are also inclosed in these cells. The scarcity of these bodies makes it probable that the disease is not longer progressing. Cultures were made by transferring a loop of heart's blood and a loop which had been forced into the liver through a scorched area to inclined agar. The blood culture remained sterile. The liver culture contains manifestly several species, only one of which was studied, and found to resemble B. coli. Turkey No. 7.— Received from a dealer the intestines of 16 turkeys for examination. In one of these there was disease limited to one ciecum. (See page 22.) Turkey No. S (Farm C).— Received about August 3 and cooped temporarily. Found dead August 6; alive the day before. The lesions in this animal are restricted almost entirely to the caeca. In one caecum the mucosa is beset with about eight peculiar elevations, which have a central yellowish slough and a surrounding infiltrated zone, making the whole crater-like body about three-eighths of an inch in diameter. On the serous surface some of these necroses show as whitish, discolored areas, with injected border. The other caecum contains but one ulcer. In the liver several small areas are found which appear necrotic, but whose nature is doubtful. Transverse sections of a portion of the wall of the ciecum hardened in alcohol jf were made through one of the ulcers. The mucous membrane had sloughed away over the center of the ulcer, and the submucous tissue and the muscular coat were extensively infiltrated Avith masses of cells. Two cultures were made on inclined agar, one with a loop of heart's blood, the other with a bit of liver tissue. The latter remained sterile. From the former two bacilli were isolated, one corresponding to B. lactis aerogenes, the other to B, coli. Turkey No. 9 (Farm D). — Brought to laboratory dead. Probably 3 months old. The disease is restricted to the ca»ca and the liver. In one caecum there are three, in the other four, thickenings of the wall, which appear as opaque yellowish spots under the serous covering. Two thickenings are situated near the blind end, the rest near the attached end. From the mucous sur- face they appear as yellowish spots from one-eighth to three-sixteenths of an inch thick in the center and thinning out from that point. The liver is beset with large, isolated and confluent roundish patches of a grayish color, mottled with yellowish specks. The same appearance is presented by the cut surface. In crushed preparations of the liver a few round, uniformly granular bodies, some within what appear to be the remnants of cells, detected. Sections of liver tissue hardened in alcohol present the usual appearances charac- teristic of the disease. Sections passing through the circular spots show that a considerable area of such spots consists of the homogeneous meshwork resulting from necrosis and fusion of the liver cells. In some of these, giant cells are situ- ated, singly or in groups, many of them inclosing vacuoles which represent the former seat of microparasites. The regions not occupied by necrotic tissue are largely made up of cells which have a small, round, densely-stained nucleus, envel- oped in considerable protoplasm. The nature of these cells is unknown, although it is probable that they correspond to the round cells in the inflammatory processes of mammalia. In the liver tissue beyond the diseased circle isolated foci are pres- ent, which are made up mainly of the cells described and gome interspersed giant APPENDIX. 31 cells. Throughout the diseased area the various cell forms are undergoing degener- ation. This manifests itself hy a breaking up of the nuclear (substance into stained granules of limited number. This phenomenon is especially frequent in the epithe- lium of the bile ducts, and more rarely the giant cells themselves show this degener- ation. Sections were also made through one of the thickenings in the wall of the caeca. These showed that the thickening was due in the main to a very extensive cell infiltration of the submucosa and of the muscular portion of the wall. Under the serosa the blood vessels are much dilated, and gorged with red corpuscles. The mucosa is not thickened, but is more or less infiltrated at the base. Much of the epithelium is gone, both of the surface and of the tubules. The microparasites are poorly preserved, but a little scrutiny shows them to be present in certain regions of the mucosa, submucosa, and rarely in the cell masses between the displaced muscular bundles. In the mucosa and submucosa they have invaded large patches, and here they are ranged side by side and are inclosed in a reticular tissue, each parasite by itself. Giant cells are also present in groups, usually consisting of little else than a mass of parasites enveloped in a nucleated network of protoplasm. Turkey No. 10 (Farm E). — Probably 8 to 9 weeks old. Supposed to be infected because unthrifty. Cooped for a few days. When killed no lesions found. On the skin were some ticks and lice: in the intestines a few tapeworms. Turkey No. 11. — From the same flock and in the same condition as No. 10. No lesions found when animal was killed. A few ticks on border of meatus of ear. Lice abundant. Turkey No. 12 (Farm C). — Probably 3 weeks old. Cooped for a week before it was killed. A few flagellates in blood from veins of skin. Tapeworms iu upper small intestines. In soft contents of caecum immense num- bers of flagellates. No disease of caecum or liver. Two cultures made with bits of liver added to agar remained sterile. Turkey No. 13 (Farm F). — Brought alive, because suspected of being diseased. No lesions discovered on dissection. Many small tapeworms in duodenum. In ca-cal contents many flagellates. Turkey No. 14 (Farm G). — About 3 months old. Taken from a flock August 8 be- cause of lack of strength to keep up with the rest when driven. Indications of diar- rhea. Placed in a coop, where it died diiriug the night. Examined next morning. Slight odor of decomposition. A few small warts on skin of neck. The various organs were found normal, with the following exceptions: Mucosa of duodenum' almost blackish, from intense injection and pigmentation of villi. Both cjeca diseased. The left is slightly distended. On serous aspect two yellow- ish spots, with markedly injected binders, corresponding to thickenings of the walls near the blind end of tube. The mucous surface of one is smooth ; to the other an exudate is attached. Besides the thickening at these spots, the free half of this caecum is somewhat thickened uniformly. The right c;ecum is very much distended over two-thirds of its length. From the serous surface local thickenings are recognizable, which have a yellowish, mottled appearance. The small intestine is firmly attached to one of these. The disease has, however, not invaded the wall of the latter. The border of these spots is intensely hyperaemic. When the ca;cum is slit open its width is three to four times that of the undistended tube, and the thickness of the wall varies from one-eighth to one-half of an inch, being not less than one-eighth of an inch over three-fourths of the entire length. When the brownish feces were washed away the increased local thicken- ings were found covered with firm exudates, usually attached in but one spot. Sections were examined of that portion of the csecal wall which was very much thickened, and to which the contiguous small intestine was inseparably attached by the new growth, ^ 32 INFECTIOUS DISEASES AMONG POULTRY. The mucosa of the caecal portion had sloughed away, while that of the emhedded small intestine was intact. The neoplastic tissue between caecum and intestine was fully 1 cm. (two-hfths inch) thick. Inasmuch as the infiltration probably fol- lowed the narrow mesentery between caecum and intestine the original boundary lines of the caecal wall are no longer recognizable. The muscular coat of the caecum- may be traced for only a short distance into the neoplasm, when it disappears. Micro parasites were not seen distinctly in the diseased tissue. The liver is very much enlarged, and dotted everywhere with roundish spots of varying appearance. The majority are from 5 to 12 mm. in diameter, round or slightly oval. The center of each is usually occupied by a group of yellowish dots and the circle is bounded by a narrow yellowish ring. The space of the circle is mottled brownish. Among these spots there are also circles of a completely yellowish color On the convex surface of the left lobe there is a very firm, ring-like, yellowish mass, cutting like firm cheese. In crushed preparations of fresh liver tissue from within the brownish circles many giant cells are seen. They consist of a meshwork of protoplasm of a rather coarsely granular character inclosing spheres which appear homogeneous. The giant cells are up to 30 // in diameter. Sections of liver tissue hardened in alcohol and in Foa's solution were also exam- ined. The foci of disease contain necrotic areas in which are numerous giant cells each inclosing a number of microparasites. In some portions there is much cell infiltration in the interlobular tissue around the portal vessels. Among the cells the protozoa are recognizable. Turkey No. 15 (Farm H). — Obtained alive and killed. About 3 months old. No caecal or liver disease detected. In duodenum numerous tapeworms. This turkey had probably been injured, for blood extravasation was found under skin of skull. Turkey No. 16. — About 3 months old. Obtained with No. 14 from the same Hock (Farm G). Suffering with diarrhea. After being cooped for two days it was killed August 10. The blood taken from a cutaneous vein of the breast under the wing showed extensive leucocytosis. The digestive tract is normal, with following exceptions : The mucosa of duodenum is hypera-mic. Tapeworms absent. The rectum, i. e., the bowel from the cseca to cloaca, is also hypersemic. It contains yellowish masses made up of microscopic spherical crystals (urates). Both caeca are affected. Contents of a pasty, brownish (nearly normal) character, containing a considerable number of microparasites. Flagellates not seen. The disease is manifested in both c;eca symmetrically by a thickening of the walls of the distal half of each tube. There are a few yellowish Spots noticed under the serous covering of the thickened region. These correspond to spots of maximum thickness. The mucous membrane appears intact. The slight pigmentation noticed on the mucous folds is frequently present in caeca otherwise normal. In tangential sections of the thickened wall in the fresh condition considerable numbers of round microparasites, of a homogeneous-appearance, and about 8 to 10 n in diameter are seen. They are not bound to cells, but appear to be displaceable under the cover glass independently. In transverse sections of one caecum hardened in corrosive sublimate and alcohol the increase in thickness of the wall was found to be due to hyperplasia of the sub- mucous tissue and cellular infiltration of the muscular coat. The mucosa itself was intact, the epithelium in place. Interspersed in the hyperplastic suDinucosa are small nests of giant cells, some containing well-defined micioparasites, others only vacuoles, somewhat larger than the parasites. The latter are not diffusely scattered through the tissue, but restricted to these and a few other foci in which they exist free in the meshes of the tissue. The masses of cells between the bundles of muscular fibers resemble those of the submucosa and are free from parasites. The liver is considerably enlarged. The surface is not .smooth but slightly rough- ened. Scattered over the various surfaces there are in all six or seven yellowish-white APPENDIX. • 33 homogeneous sclerotic areas which correspond to masses in the liver tissue. In cut- ting into the liver these foci are found to sheath the hepatic veins. Outside of these sclerotic foci the liver tissue is mottled with gray. In general, the entire liver appears to have passed through a process of sclerosis. In sections hardened in Foa's solution and in corrosive sublimate the pathological change going on is shown to he essentially a sclerosis following the protozoan infec- tion. Within the disease focus the liver tissue, recognizable as such, is present only in irregular patches of variable extent. The remainder has been replaced by an actively developing connective tissue, still rich in nuclei. Within these areas there is an extensive formation of bile ducts. Parasites were seen in but one spot, where a number of multinucleated cells had ranged themselves around what appeared to be an old thrombus. Here, beyond the encircling giant cells, a group of similar con- tiguous cells contained a small number of protozoa. The encircling cells themselves also contained a few, and one parasite was recognizable within the thrombus itself. Outside of these spots undergoing repair, the blood vessels are everywhere inclosed in sheaths of new connective tissue very rich in nuclei, encroaching slightly upon the liver tissue itself. Turkey No. 17 (Farm I). — About 3 months old. Found August 11 in a dying condi- tion in a tlock in which a considerable number had died during the past month. The only lesions found were a rather pale condition of the organs. In the small intestine numerous tapeworms. No liver or ciecal disease. In the caeca feces arc rather dry, and contain a considerable number of coccidia, varying slightly in size, the largest 32 n long and 18 fi broad. Turkey No. IS. — From the same flock as No. 17, and quite sick when found. Killed and placed on ice over night. In this bird no marked lesions of any kind were noted. The duodenum was hypenemic and contained more or less mucus. The contents of caeca are fluid and contain numerous flagellates. Cultures on agar from blood and liver remain sterile. Turkey No. 19 (Farm J). — About3 to 4 months old. Taken August 11 from a large flock, because suspected of being diseased. Died shortly after being caught. Placed in refrigerator over night. In the pleuroperitoneal cavity a dark clot and much blood-stained fluid ; ecchymosis of the left abdominal wall. .Source of hemorrhage not detected; probably brought on while being caught. Organs very pale but not diseased, with exception of liver and the right caecum. In the latter there are two diseased areas. Near the blind end there is a ring-like thickening of the wall, which has a yellowish color from the serous aspect. The other area is covered with a small mass of exudate, and the thickening of the wall beneath it covers an area about one-half of an inch square. The remainder of the caecuni pigmented in spots and lines. The liver is very much larger than in the normal condition and covered every- where with circular spots of varying appearance. There arc : (1) Two completely necrotic, yellow masses of cheesy character, one in the base of each lobe. (2) Circles of a grayish-yellowish color throughout. (3) Spots of a mottled brownish appearance. The mottling represents distended vessels. (4) Spots like the preceding with a necrotic mass in the center. These spots vary in size up to a diameter of three-fourths of an inch. In crushed preparations of the fresh liver the microparasites are distinctly rec- ognizable. Some appear as free granular bodies, others are inclosed, either singly in a cell, or in groups in large cells. These inclosed bodies are usually free from granules and may show a minute nucleus. They measure from 10 to 13 // in diameter, In sections of liver tissue from this case hardened in alcohol the lesions were found to correspond to those in other cases. Sections through a brownish spot showed everywhere marked distension of the vascular channels. These were tilled with 17897— No. 8 3 34 INFECTIOUS DISEASES AMONG POULTRY. corpuscles. The parenchyma has largely disappeared and small cells have taken its place. In a few places of the section microparasites are found collected together in large patches. In these, giant cells are occasionally seen. Turkey Xo. 20 (Farm I. see Nos. 17 and 18).— Found in field resting on keel and moving along ground with aid of wings. Obtained August 11. Killed and exam- ined August 12. In trachea six pairs of gapeworras attached. In caecum and rectum a yellowish fluid (urates) containing many flagellates. No disease of liver or caeca. Turkey No. 21 | Farm K).— Picked out of a large flock August 11, 1891, because it was much weaker than the rest. No distinct appearances of disease. When killed the organs were found normal, with the exception of the intestines. A mass of exudate lying adjacent to rectum in abdominal cavity binds together rectum, tueca, and neighboring coils. Tim mass has a cylindrical shape and is about 2 inches long and three-fourths of an inch at greatest diameter. It consists of spongy yellowish exudate, incased in a smooth, leathery capsule. There is no disease of the mucous or submucous tissue in any part of the intestines. The exudate is evidently the result of a tear in the rectum which permitted the escape of feces into the abdo- men. These became subsequently permeated with and encased in fibrin while the tear healed up. Odor of this mass strongly fecal. A bit of liver tissue is placed on inclined agar. The latter remains sterile. Turkey No. :2. — Large female, over 1 year old. Died on Block Island during the night of August 12. Examined on the farm next day. No evidence of liver or caecal disease. In abdomen a partially smashed eggshell attached lightly to mes- enteries. Turkey Xo. 23 (Farm L). — About 3 months old. Received, dead, by express August 14. Probably died two days ago. Slight odor of decomposition. Duodenum very much discolored by pigmentation. Both caeca considerably dis- tended. The left is normal, the right diseased. Fully one-half to two-thirds of its entire length beginuiug with the blind end is thickened. There are a number of centers where the thickness is increased. At one of these there has been an out- pouring of exudate on the serous membrane. The mucous surface of these local thickenings is covered with firm masses of exudate. The liver contains one sclerotic focus which has a whitish mottled appearance. It is otherwise normal. Three adult pairs of syngames in the trachea. In sections of the wall of the greatly enlarged caecum hardened in alcohol the lesions were of an advanced character. The mucosa was almost entirely sloughed away. Only a few remnants of the slough remained, containing some tubules recog- nizable as such. The submucous tissue was greatly thickened by cell infiltration, and the muscular coat was divided into sections by cell masses which exteuded to the serous membrane. Under the latter the blood vessels appeared greatly dilated and filled with corpuscles. The microparasites are still present, but in small num- bers. They appear in the neoplastic tissue in small patches inclosed by a fringe of round cells. Giant cells are numerous and arranged in groups. Only in one group were microparasites inclosed. Turkey Xo. 24. — Taken August 13 from a flock ou Block Island, because it was sus- pected of being diseased. Killed August 14. No lesions were discovered in the organs. One gapeworm found in the trachea and several minute tapeworms in the intestine. Turkey Xo. 25. — Taken from the same flock. When killed disease was found in one of the caeca. (See page 22. ) Turkey Xo. 20. — About 3 months old. Brought August 15 from a large herd (Farm G), and reported as having been feverish for a few days past. The bird is killed and found in well-nourished condition. Disease limited to one cwcuni and to the liver. Fully one-third of the caecum has its wall thickened. The thickening is most pronounced in spots, to some of which a APPENDIX. 35 firm, pale-yellowish exudate is attached. A portion of the diseased tube is placed unopened in hardening fluids for farther study. The liver is enlarged t<> two or three times its normal size, and uniformly per- meated with closely set. but usually discrete, spots, varying in si/e. a few having a diameter of one-fourth of an inch. They are of a yellowish - g due to a fine yellowish network, of which the spot is in fact mad.' up. The details are well shown in the photographic reproduction and in the colored draw g III. figs. 1. 20 In teased and crushed preparations ot' the fresh liver a large number o{ mi parasites are detected. They appear as round, pale, horn g - :h a sharp line as a border. They are less refrangent than fat globules, and su„_ it somewhat the color and refrangibility of myelin or Bui V$ - - they are found in the alveolar epithelium of the lungs of cattle. Their diameter ranges from 12 to 14 a. Some are surrounded by a narrow rim of protoplasm, containing one or more nuclei, evidently the remains o{ a cell. Transverse sections of the diseased ca-eum show a mass of exudate occupying a portion of the lumen. In the exudate are embedded strips of perfectly preserved epithelium. Tin' exudate appears amorphous and contains small foci and even large patches oi cell masses, probably originating from the inttammatory processes going on. The thickening of the wall is due in this case chiefly To infiltration of the sub- mucous tissue. In one portion of the sections the muscular portion of the wall is infiltrated to the serons covering. Parasites are. however, not detected in the sub- mucous or muscular cell masses, but are situated exclusively and in very large iuim- bera in the reticular tissue of the mucosa, between the crypts. In this tissue, as well as in the epithelium of the crypts, numerous mitotic figures au kble. Giant cells are also present, but m small numbers. The micro:' generally singly, in cavities surrounded by one or more nuclei. In some places tew or many may be detected, packed away in a space of the reticular tissue. The parasites are well brought out m the tissue hardened in corrosive sublimate and alcohol, and stained in hematoxylin and eosin. They a] - round or slightly oval bodies, with a faint reddish tinge of the body and a'lninute blue, ring- like, central or eccentric body, probably the nucleus wry from t ; diameter. The lumen ol' the mucous gland is densely packed with bodies roundish in outline and about 4 u in diameter. The cell body is stained a homogeneous red with eosin. the nucleus bluish with hematoxylin. v S(,t ' P»g« 200 Sections of the lt\ er w ere made front material hardened in alcohol and in cor: • sublimate and alcohol. They were stained in various w ays, the most satisfactory stain being hematoxylin and eosin. by which the nucroparasite was most clearly brought out. Methylene blue was also satisfactory in bringing the mioroparas into relief. The sections show within sonic of the areas indicated by the yellowish spots extensive disappearance o( the liver cells proper and the presence ot a meshwork or network of a homogeneous subs:. nice, which suggests a fibrinous exudate, although it has not the librillated structure o( mammalian fibrin. This meshwork is not uni- formly distributed over the affected area, but appears ua foci which are connected with one another. The space left is occupied h\ numerous parasites ami giant cells and an occasional group o( liver cells. In other foci the liver cells are replaced by a reticulum containing numerous parasites. Usually but one parasite is contained in a mesh and is elosoh surrounded b\ one or more nuclei. Turkey So. 37. — Taken from another Block [slant! Book as a auspioious About 3 months old. No lesions found in tins bird. In the trachea three gapew onus ; in the intestine main large tapeworms. Turkeys Aw, 98 and 9, Brought from Fishers Island, N<» JTork No lesions m these oaseQ Manx large tapeworms n>. the intestine, 36 INFECTIOUS DISEASES AMONG POULTRY. Turkeys Nos. 30 and 31 (Farm J). — About 3 to 4 weeks old. Brought because they were not doing well. Killed. Intestine found nearly occluded with small and large lapeworras. Turkey No. 32 (Farm C). — About 3 months old. Killed August 17. No lesions found. In duodenum several tapeworms. In caecum flagellates. Turkey No. 33 (Farm B). — About 3 months old. In the blood from a subcutaneous vein some flagellates. No lesions in the internal organs. In duodenum some tape- worms. Turkey No. 34. — Obtained from Farm K August 18. Died on the way to laboratory. Bird about 10 weeks old. In body cavity blood-stained fluid. One-half of the left caecum, beginning at the blind end, has its wall thickened. The serous covering js reddened and shows a few yellow patches which correspond to certain specially thickened regions of the wall whose mucous covering is necrosed. The liver is large and covered everywhere with rather large, round, dark-brownish patches having a narrow, yellowish boundary line. These correspond to diseased foci within the liver. In fresh liver tissue, crushed or cut in sections, oval bodies 12 to 15 /< in diame- ter are present inconsiderable numbers. They appear homogeneous; contents not differentiated. Similar bodies, inclosed in groups of two or three in large cells, are also present. They are homogeneous, round in outline, from 8 to 12 u in diameter. In sections of liver tissue hardened in alcohol, when examined with a low power, an immense number of microparasites appear embedded in the tissue. These vary but slightly in size (8 to 9 fi). Throughout the invaded spot the blood vessels, large and small, are irregularly dilated and filled with red corpuscles, among which the parasites are not seen. The tissue between the blood vessels is no longer recogniza- ble as hepatic tissue. In some parts of the section it consists in the main of the round parasites, single or in small groups, each individual or group inclosed in a rim of protoplasm provided with one or more nuclei. There is thus inclosing the para- sites an imperfect meshwork present whose origin and nature is not evident. In some places it would appear that the parasites are embedded in the liver cell. The nuclei of such cells have undergone proliferation and some of these proliferated cells have degenerated into groups of minute, deeply-stained granules. The impression conveyed by such cells is that they are giant cells. They differ, however, from those giant cells which appear in a later stage of the disease. The meshwork of tissue which has undergone necrosis is present in but a few small areas. Turkey No. 35. — From the same flock as No. 34 (and No. 21). Obtained August 18. Died on the way. This case closely resembles the preceding. One-half the length of both cieca involved. The walls are thickened uniformly and in this portion are some small excrescences easily removed in tolo, leaving only a slight depression. Liver spotted on all surfaces as iu preceding case. Duodenum blackish from injection and pigmentation. Muscular tissue has a yellowish tinge. In the trachea one gapeworm, and some roundworms in the duodenum. Turkey No. 36 (Farm N). — About 3 months old. Obtained, just dead, on August 18. In tli is case the liver and ca-ca are diseased. The liver is spotted on all surfaces. The spots vary in appearance. A few have a mottled, pale-yellowish aspect and are fully 1.5 cm. (three-fifths inch) in diameter. The remainder are round blotches of a mottled, dark-brownish appearance. Many of these have coalesced into small groups. The wall of the left caecum is very slightly thickened and still smooth. The right is in the same condition. At the middle it has a circular ring-like thickening, about 2 cm. (four-fifths inch) wide, of a yellowish appearance on section. Sections were prepared of this region after hardening the entire caecum iu alcohol. The thickened wall, about 8 mm. in diameter at the thickest portion, consists entirely of neoplastic tissue. The mucous layer is gone and the muscular layer is APPENDIX. 37 no longer recognizable. The bulk of the enlarged wall is composed of small cells, in which are interspersed in round and elongated patches large numbers of multinu- cleated cells, much smaller in size than the giant cells usually encountered. The cells do not distinctly show the microparasites within their suhstauce except in a few cases, probably owing to the time and manner of hardening. Turkey No. 37. — Obtained August 18 from Farm O. About 4 weeks old. Died the following night. No lesions found, although intestine contained many tapeworms. Turkey No. 38. — From the same Hock as preceding. About 3 months old. Died during the following night. No lesions. One gapeworni in trachea, and very many small tapeworms in intestine. Turkey No. 39. — From the same flock. About 9 weeks old. Died the following night. Numerous tapeworms in intestine. Turkey No. 40. — From the same flock August 18. Cooped until August 20. On that day the bird was resting on its breast with eyes closed. Killed. Many small tapeworms in intestine. Turkey No. 41. — Probably 8 weeks old. Brought to laboratory August 18, 1894. Cooped temporarily and found dead August 20. Disease in this case limited to both ca3ca. ( See page 22. ) Turkey No. 42. — Obtained August 18 from Farm I. About 3 mouths old. Sus- pected of being diseased. When killed no lesions were detected. Turkey No. 43. — Obtained August 18 from Farm P. Cooped. Found dead August 20. The only discoverable lesions were a puffing out of the tissue below one eye, due to accumulation of a glairy secretion (roup). The same exudate found in the trachea. Agar tubes inoculated with tracheal exudate remained sterile. Numerous tapeworms in intestine. Turkey No. 44. — Obtained from Farm Q August 18. Many turkeys are reported to have died on this place. Bird about 3 mouths old. No lesions found when it was killed. Many tapeworms in intestine. Turkeys Nos. 45, 46, and 47. — Obtained from Farm R August 18 and cooped for several days. When killed nothing abnormal detected. A few tapeworms in the small intestine of No. 45 and No. 47, and many in No. 46. In the semiliquid eon- tents of the c;eca of No. 47 very many flagellates. Turkey No. 48 (Farm S). — Obtained August 18. Cooped until August 21. Bird appears well. When killed a few tapeworms were found in the intestine. Turkey No. 49. — Received August 18, from a dealer, the intestines of nine turkeys, In only one of these slight traces of csecal disease. This is manifested by a nodu- lar, roughened condition of the mucosa of one caecum near the attached end. In all intestines tapeworms present. Turkey No. 50. — Obtained September 26 from a farm in the District of Columbia. Slight odor of decomposition. The internal organs are free from disease. In the trachea one pair of gapeworms. The head is badly diseased. On the root of the bill a projecting tumor overlapping the nares, which is about two-thirds of an inch in diameter. It is of a soft, medullary character and has a wart-like structure. Besides this large tumor there is a small nodule on the lid of left eye. Right eye completely closed by excrescences on the lid and cheesy masses in conjunctival sac. Cornea opaque. In one nasal passage a large cheesy mass. No liver or csecal disease. Turkey No. 51 (Farm B). — Received from Mr. Cushman, Kingston, R. I., Octobers, 1894. Died on the way. Turkey quite large; probably 5 months old. Decompo- sition well advanced. The disease in this case was limited to the cieca, the liver, and the peritoneum. The intestine was covered in places by a firm, yellow pseudomem- brane fully 1 mm. thick, and the coils were glued to each other so that they could be separated only after much dissection. The caeca appeared as an irregular mass partly covered with the pseudomembrane. Attempts to dissect out both ca-ca were fruitless, as they were firmly attached to each other. Only one was diseased, how- ever. This was much enlarged, its walls thickened, and the mucous membrane 38 INFECTIOUS DISEASES AMONG POULTRY. beset with large, firm masses of exudate. In the liver were two foci of disease, each about 1 cm. in diameter. One is made up of firm, pale-grayish tissue, probably largely cicatricial; the other is similar in appearance, but has small, yellow, cheesy masses disseminated through it. Owing to the very advanced stage of decomposition, cultures were not made. It was evident, however, that the cause of death was the septic peritonitis, which was secondary to the ctecal disease. Turkey No. 52.— Received, dead, with No. 51. Large male bird; probably 5 months old. Very little decomposition. Head free from disease. Heart and lungs normal. The pleuroperitoneal cavity contains a large amount of blood-stained serum. Serous coat of gizzard very much injected. Serous coat of proventrieulus dotted with elevated yellowish points and lines where the diseased liver lay in contact with it. Spleen small, contains a minute yellow focus; probably also the result of neighboring disease of the liver. Duodenum, and a portion of the intestine below it, intensely hyperaemic and pig- mented. A few small tapeworms present. Pigmentation and hyperemia gradually become less and disappear near openings of caeca: Below these the intestine is coated witli a yellowish liquid, largely composed of urates. Both caeca contain pigment spots, ami the longitudinal folds are pigmented. In one caecum, near the blind end, there is a thickening of the wall about half an inch across, covered with a brownish-yellow slough on the mucous side. The serous aspect is discolored, in part yellowish. This is the only lesion found in the caeca. The liver is very large, weighing 304 grams (10.7 ounces). It is extensively dis- eased. The lesions are best described by grouping them under several heads: (1) Necrosis of the liver tissue is present in both lobes in the form of large and small masses of yellow, firm, cheesy masses (PI. Ill, fig. 2). In the left lobe fully one-third of the lobe is converted into a single, yellowish, homogeneous mass, situated at the base or attached portion. The necrosed tissue is sharply defined from the adjoining living tissue by an irregular line. The main branch of the hepatic vein is bounded by the necrosed tissue, and the branches from the dead mass are occluded with pale, friable thrombi. In the right lobe, at the base or attached portion, there are several quite large cheesy masses of very irregular outline embedded in the living tissue and in part visible on the surface. Besides these large masses there are dis- seminated through the liver numerous smaller masses of cheesy tissue, either singly or in groups. These small foci arc usually associated with reparative processes. (2) Foci which have healed and cicatriced wholly or in part are represented by isolated regions, varying in size and attaining a diameter in one case of three-fourths of an inch. The appearance of these foci varies considerably. They may show as pale pinkish-gray spots penetrated by a network of vessels corresponding to the interlobular markings. Others may be the seat of scars and slight depressions char- acterized by increased vascularity and a pale pinkish-gray appearance on the liver tissue. Finally, they may be intermingled with small cheesy foci, which are located either centrally in the healed region or in numerous foci around it. Over the entire surface of the liver patches containing networks of enlarged ves- sels having a blackish color give the liver an injected appearance. There is nowhere an indication that the disease as such is still going on. The extensive destruction of liver tissue, as well as the repair, appear to be the result of an invasion of proto- zoa now completely checked. The false membranes which cover some of the healing spots on the liver and the abundant fluid in the abdominal cavity indicate a secondary infection with bacteria through the necrosed tissue. A PRELIMINARY INVESTIGATION OF DIPHTHERIA IN FOWLS. By Veranus a. Moore. [With I*]. VI.] It is well known that a disease which is characterized by tin- forma- tion of mi exudate on one or more of tin- mucous membranes of the head is widely distributed among the fowls of this country. Although its existence is of long duration its cause and the character of the exudate have not been satisfactorily determined. In Europe outbreaks of a malady comparable to this in their manifestations have been described as epizootics of fowl diphtheria. There sue in this country a few popular articles on diphtheria in fowls, but. generally speaking, the term most frequently employed to designate a disease on the heads of poultry is ''roup.'" 1 The range of morbid anatomy which this term originally indicated is not known, but its present conception is exceed- ingly broad, including, as shown by the American literature.- nearly, if not all, the noticeable disorders of the heads of poultry. Writers differ in reference to the nature of this d; Bfany poultry raisers consider it a local affection, having its origin in the improper care of the fowls, while others insist that it is a highly con- tagious disease. The latter class strengthen their position by clinical history, in which they show that fowls which had previously been free from this disease soon became infected after the introduction of one or more "roupy" fowls into their midst. Reports show that it is the usual experience that when the di introduced it almost invari- ably remains in a more or less chronic form for an indefinite period. notwithstanding the adoption of the best known methods of caring for the fowls. It is stated by Bennett that --it is undoubtedly ti 1 The origin of this term is somewhat obscure, but it iss I to be a corruption of croup, and its application explained on account of a peculiar ho .: om- pauying the respiration of the affected birds. -This literature is confined for the greater part to articles in poultry an reparations made from the lesions of the affected fowls were carefully stained and examined. 3 Those prepared from the surface of the exudate and from the necrotic masses generally contained innu- merable bacteria, but no predominating species was observed. Similar preparations from the base of the exudate in the more recent stages con- tained a large number of short bacilli with the ends rounded. These forms frequently exhibited a polar stain. Several preparations were 'A large number of species of bacteria were isolated and studied somewhat carefully. Among them are several quite interesting forms, some of which were suspected to be of more or less economic importance. Prominent among these was a bacillus which resembled morphologically and in certain of its cultural characters the bacillus of tuberculosis. It was not pathogenic for guinea-pigs or fowls, and did not take the Koch stain. 2 It is of interest to note that several varieties of colon bacteria were isolated in this way. One of tbese possessed such variations from the colon bacillus in its cul- tural manifestations and it was possessed of such marked pathogenesis that for a time it was suspected of bearing some causal relation to the disease. It was briefly described in a footnote on page 43. 3 In both fresh and stained preparations a long spirillum was found to be quite abundant. It was from 2 to 4 11 in length. Thus far I have been unable to detect it in artificial cultivations. SUMMARY OF INOCULATIONS. .55 stained for tubercle bacilli, but with negative results. A summary of the results obtained from animal inoculations is appended in tabulated form Animals inoculated with the exudate from affected fowls. Animals inoculated. Inoculated with exudate front- Date of inoculation. Results. Remarks. Rabbit No. 117... Eye, fowl No. 1 Dec. 28,1893 White mouse. Do Rabbit No. 144. Rabl.it No. 145. Rabbit No. 97.. Rabbit No. 149. Guinea-pig 222. Guinea-pig 223. Guinea-pig 209. Fowl No. 50.... Fowl No. 54 Fowl No. 55.... Rabbit No. 215. Rabbit No. 223... Rabbit No. 226.. .do i Jan. 23,1894 do Nares, fowl No. 3 . do Nans, fowl No. 4. . Nans, fowl No. 5. . Mouth, fowl No. 61. Nares, fowl No. 62. Mouth, fowl No. 59. Eve, fowl No. 65. E've, fowl No. 68. . .'..do Eye, fowl No. 69. Eyes, fowl No. 71.. Nares, fowl No. 75. do Feb. 4, 1894 Feb. 24, 1894 do Feb. 29, 1894 Oct. 9, 1894 do Oct. 20,1894 Oct. 24,1894 Oct. 27,1894 do Nov. 2,1894 Nov. 5,1894 Nov. 22, 1894 Died Feb. 10,1894 Died Jan. 27, 1894.. J Heel. Jan. 29. 1894.. Died Feb. 28, 1894. Died Feb. 25.1894. do Died Mar. 1,1894.. Chloroformed Oct. 13, 1894. Chloroformed Oct. 15, 18114. Chloroformed Oct. 25, 1894. Remained well do ...do Found dead Nov. 5, 1894. Found dead Dec. 19, 1894. Found dead Nov. 23, 1894. Rabbit very much emaci- ated ; no bacteria found in its organs. Enlarged and discolored spleen; a pathogenic inu- tile bacillus. Spleen enlarged; nonmo- tile pathogenic bacillus. Septicaemia; nonmol ile pathogenic bacillus. Do. Do. Do. Local lesion contained l',a- dlluS COli ro)u in unit. Do. Local lesion contained non- motile pathogenic bacil- lus. No local reaction. Do. Do. Plenritis; hemorrhages in the intestines; nonmo- tile pathogenic bacillus. Pleuritis and peritonitis; nonmotile pathogenic bacillus. Septicaemia; nonmotile pathogenic bacillus. The table shows that the pathogenic bacillus was obtained from the lesions of fowls Nos. 1, 3, 4, 5, 59, 69, 71, and 75, or nearly 50 per cent of those examined. It is a significant fact that the bacillus was obtained from all the fowls but one (No. 61) where the lesions either in the eye, nares, or mouth were not far advanced. In one case (No. 73) no inoculations were made. The almost constant appearance of this bacil- lus in the more recent lesions renders the apparent small percentage of cases from which it was isolated of much greater importance than it would at first be considered. A comparative study of the bacteria from the different fowls showed that those obtained from fowls JSos. 1, 59, 69, and 71 were attenuated in varying degrees, while those from the other cases were sufficiently virulent to destroy rabbits within twenty-four hours. This variation in the degree of virulence of the cultures obtained from different fowls is interesting and important. There was no differ- ence in their cultural characters. A glance at the post-mortem notes will show that in the fowls from which the attenuated forms were obtained the lesions were apparently older or more advanced than in the other cases. In previous investigations ' rabbits were inoculated with the nasal and pharyngeal secretions of several healthy fowls. These rabbits 1 Bulletin No. 3, Bureau of Animal Industry, 1893, p. 47. 56 INFECTIOUS DISEASES AMONG POULTRY. remained perfectly well. Although septic bacteria are known to be common in the secretions covering the normal mucosa of the upper air passages of several species of domesticated animals, such organisms have not been reported from the mucosa of healthy fowls. In 1890 two fowls 1 which died very suddenly at the experiment sta- tion of this Bureau were examined. One of them exhibited a croupous exudate extending from the larynx into the trachea, and the other a swollen condition of the mucosa of the mouth and oesophagus. No pathogenic bacteria were obtained from the fowl suffering from the exu- date, but from the other were obtained pure cultures of a bacillus not distinguishable from that of swine plague. It is impossible to positively identify the pathogenic bacillus found associated with the lesions in this disease with the one described by European writers as the cause of fowl diphtheria. Morphologically it is similar to the one described by Loefrler, but its pathogenesis is differ- ent. This may be due, however, to difference in the degree of virulence. There is much obscurity in the reference to the properties of the bacilli found by other investigators as the probable cause of diphtheritic affec- tions of fowls and birds, as their descriptions are exceedingly meager, being often limited to the morphology and possibly the character of the growth on one or two of the more commonly used culture media. In those species of pathogenic bacteria which have been more fully described a more accurate comparison is possible. Thus, the bacilli of fowl cholera, swine plague, and rabbit septicaemia are found to be com- parable with the bacillus about to be described, and found in the lesions of this disease of fowls. While it is not my purpose to discuss at this time the identity or relationship of these bacteria, it is important to know that a bacillus associated with the peculiar lesions of this disease should be so similar to the one described by European writers as the cause of fowl cholera. The more essential properties of the bacillus found, apparently the etiological factor, in the lesions of the diphtheritic disease of poultry which I have studied are appended : DESCRIPTION OF THE NONMOTILE PATHOGENIC BACILLUS. Morphology. — A nonruotile, rod-shaped organism 0.8 to 1.5 ju long and from 0.8 to 1.2 /.i thick. The ends are oval, and the shorter forms appear to be nearly spherical. In bouillon they are frequently in short chains and in clumps. When stained with the aniline dyes in cover-glass preparations made directly from animal tissues they exhibit a light center, occasionally showing deeply stained poles. In preparations from cultures this character is much less marked. No capsule has been positively demonstrated, although certain preparations suggest its existence. It stains readily with the aniline dyes ordinarily used. It does not retain the coloring matter when treated after the Gram method. Culture characters. — On agar at 36° C. the growth is not vigorous. It is of a neu- tral gray color, with a glistening, moist-appearing surface. The growth is slightly viscid, and adheres quite firmly to the agar surface. The condensation water becomes 1 Special Report on Swine Plague, Bureau of Animal Industry, Department of Agri- culture, 1891, p. 158. DESCRIPTION OF THE BACILLUS. 57 faintly clouded. Within agar the colonies appear as minute grayish dots. The growth is completed in about forty-eight hours. In agar plates (double disks) it emits a disagreeable, pungent odor, similar to that observed in cultures of the swine-plague bacillus. It does not grow in alkaline, peptone gelatin. It does not develop on potato. Milk remains unchanged in appearance for six weeks. Cultures which had grown for several days were boiled. No change was produced. Alkaline bouillon at 36° C. becomes uniformly clouded in twenty-four hours. The reaction becomes acid in from one to two days. It docs not grow in acid bouillon. In bouillon containing sugar the growth was slightly more vigorous. In the fer- mentation tubes the liquid in both branches becomes cloudy, (ias is not produced. In bouillon containing dextrose and saccharose the alkaline reaction is changed to a strongly acid one in twenty-four hours ; the bouillon containing lactose remained alkaline. In a weak solution of peptone containing salt it grew feebly, but gave a decided indol reaction. The phenol reaction was not detected. Thermal death point. — This organism is destroyed in bouillon cultures heated in a water bath for live minutes at 58 J C. Au exposure of ten minutes to a temperature of 54° C. was not fatal. Effect of drying. — The bacillus is destroyed in twenty-four hours by drying on cover-glasses at the temperature of the laboratory. Effect of low temperature. — Dry cover-glass preparations were exposed in a sterile test tube to a temperature varying from zero to a few degrees above tor a period of seventeen hours. At the end of that time they were placed in tubes of bouillon and put in the incubator. These tubes contained pure cultures of this bacillus on the following day. Disinfectants. — A few preliminary tests showed that this organism was very sensi- tive to ordinary disinfectants. To determine more accurately the streugth of the solution and the time necessary for a fatal exposure, Dr. C. F. Dawson kindly car- ried out an extensive series of experiments, the more important results of which are appended : Commercial sulphuric acid in one-eighth of 1 per cent solution destroys in thirty minutes; in one-fourth of 1 percent it kills in ten minutes. Lime water destroys the organism in one minute. When diluted four times (0.015 per cent lime) it requires thirty minutes. Carbolic, acid in strengths of 0.5, 1, and 2 per cent destroys this bacillus in sixty, five, and one minutes, respectively. The frequency with which sulphur fumes are used to disinfect chicken houses led to the testing of their efficiency on this organism. The methods and results reported by Dr. Dawson are as follows : "A drop of bouillon culture was placed upon a sterile cover-glass inside a large glass jar which had been specially prepared for the test. About a half teaspoonfiil of sulphur was placed upon a sheet of asbestus and ignited. The lid of the, jar was put on and in a short time the jar was filled with the white fumes. In three hours the cover-glasses were carefully removed and dropped into a tube of sterile bouillon and placed in an incubator. They invariably remained clear." Pathogenesis. — Rabbits inoculated subcutaneously with 0.1 cc. of the virulent bouillon cultures died in from eighteen to thirty-six hours with lesions similar to those produced by swine-plague bacteria of a virulent type. The organs contained large numbers of oval bacteria exhibiting a polar arrangement of the protoplasm. Those inoculated in a similar manner with the attenuated bacilli lived several days. They exhibited more or less severe local lesions and exudates on one or more of the serous membranes. Adult fowls inoculated subcutaneously with 0.5 cc. of a fresh bouillon culture of the virulent form remained well. A young fowl (about 6 weeks old) inoculated in a similar manner with 0.3 cc. died on the fourth day. The kid- neys were abnormally yellow in color and contained large quantities of urates. 58 INFECTIOUS DISEASES AMONG POULTRY. Other organs were apparently normal. No bacteria were found in cover-glass prepa- rations from the organs, but tubes inoculated -with, the blood and liver developed into pure cultures of the bacillus injected. Several white and gray mice were inoculated subcutaneously with pure cultures. One of the white mice died. The others remained well. Several efforts were made to produce the local disease by injecting pure cultures of this bacillus into the nasal cavity of fowls. These gave invariably negative results. Cultures were also fed in large quantities to several fowls without produc- ing the disease. The fact that diphtheritic lesions were not produced in fowls Avith this bacillus appears to be an argument against its specific relation- ship to the disease. Loeffler produced the disease in pigeons -with the bacillus he isolated In these investigations the conditions under which the inoculation experiments were made were presumably quite different from those surrounding the fowls which developed the disease. The variations in the degree of virulence of the organism from the different fowls renders it difficult to determine whether the infection depends on the virulence of the bacillus, or a predisposing condition on the part of the fowls. The etiological relation of this bacillus to the disease in question, however, is neither demonstrated nor affirmed, although the evidence in hand is quite enough to warrant the working hypothesis that it is, to a certain extent at least, an exciting agent in the produc- tion of the accompanying lesion. PREVENTION AND TREATMENT. The nature of this disease, as determined by the foregoing investiga- tions and the published statements of a large number of poultry raisers, indicates that it can be prevented, and if introduced it can be cured. Although it will be necessary to determine experimentally the efficiency of curative agents on a considerable number of fowls before formulas for treatment can be laid down, several important suggestions present themselves at this time, especially in reference to preventive measures. In order to prevent this disease it is evident that many conditions must be strictly complied with. The character of the food and the general sanitary conditions, including cleanliness, ventilation, and the temperature of the poultry houses, must be considered. Undoubtedly there is much to be learned in connection with the proper care of poul- try, especially in rural districts where it is probable that many methods now in use will, after a careful investigation, be found defective. Tbe determination of these details must necessarily be made by those actually engaged in the raising of poultry. In addition to the general sanitary methods, the following rules should be observed : (1) Fowls which have an exudate on any of the mucous membranes of the head, or which have come from flocks in which such a disease exists or has recently existed, should not be introduced among other poultry. PREVENTION AND TREATMENT. 59 (2) If the disease appears in one or more fowls of a flock they should be immediately separated from the well ones. If possible, the source of the infection should be determined and removed. (3) The quite common practice of allowing fowls from different flocks to run together during the day should be discouraged. (4) ('are should be taken to avoid the possibility of bringing the virus of the disease from affected docks in the dirt or excrement which natu- rally adheres to the shoes in walking through an infected chicken yard. The same care is necessary in the interchange of working implements, such as shovels, hoes, etc. It is evident to any careful observer that the fact is too often over- looked that fowls, owing to their method of living, are more liable to infection than other farm animals. This is especially true when they are allowed to run at random, as they too frequently are, picking their living from the garbage pile and barnyards, or securing even more un wholesome food. There is little doubt that many so-called outbreaks of contagious disease among fowls are simply enzootics brought about by improper care. The efficiency of these few suggestions in reference to the prevention of this disease is demonstrated by the success of certain poultry raisers who adhere strictly to the teachings of sanitary methods. The wide distribution, the large number of fowls affected, and the usual chronic course of this disease render it oue of the few poultry affections for which curative measures promise to be of practical value. Although prevention is the safest of cures, when the disease is once introduced as it is in a very large number of flocks, the necessity for remedial treatment is apparent, and where economy is to be considered should be recommended. The practice sometimes followed of destroy- ing all of the affected birds should be discouraged. Although experi- ments have not been made to test the efficiency of remedies already recommended, or to investigate the practicability of others, the testi- mony of many practical poultry raisers is, as previously stated, to the effect that the disease is amenable to treatment. The most certain of the known methods of treatment is the local application of certain disinfectants, among which a weak solution of carbolic acid appears to be the most satisfactory. The fact that the lesions are so much exposed renders the disease especially favorable for topical applications. The administration of mild stimulants has also been recommended. In addition to the medicinal treatment, it is of much importance that the affected fowls be provided with proper food and kept in dry, warm, and well ventilated apartments. In the course of this study a considerable number of badly affected fowls fully recovered in the animal room of this laboratory with no treatment other than a warm, dry atmosphere. If the disease has reached its third stage, it is frequently necessary to remove the sloughed exudate, which is retained on account of the 60 INFECTIOUS DISEASES AMONG POULTRY. attachment of its margins, before the application of the disinfectant. A few fowls have been received where it was evident that death would soon have followed from starvation or a closure of the respiratory pas- sages, and which were immediately relieved and cured by removing the obstructing exudate. There are certain disinfectants and stimulants recommended, which I am advised will give good results, if adminis- tered early in the course of the disease, by mixing them with the food and thus eliminating the necessity for individual application. THE RELATION OF DIPHTHERIA IN FOWLS TO PUBLIC HEALTH. A comparison of the bacillus of diphtheiia in man (Klebs-Loeffler) with the one described by Loefrler as the cause of diphtheria in fowls, shows that morphologically and in their pathogenesis for experimental animals the two organisms are in no way alike. There is also a marked difference in the nature of the exudates in fowls ami in man. The non- identity of these diseases has been clearly pointed out by Menard. 1 Although these diseases are shown by several observations to be unlike in their etiology and the character of their lesions, the transmission of fowl diphtheria to the human species, and vice versa, is affirmed by several writers. Gerhardt 2 reports 4 cases of diphtheria among workmen who had charge of several thousand fowls, many of which died of diphtheria, in Wesselhausen, Baden. There Avere no other cases of diphtheria in the neighborhood, and the evidence was quite conclusive that the dis- ease was contracted from the affected fowls. It is also stated that an island on the northeastern coast of Greece had been free from diph- theria for at least a third of a century, when a dozen turkeys, several "of which were diseased, were introduced. Soon afterwards diphtheria appeared in a house near the garden where the turkeys were kept. The disease became epidemic on the island causing the death of 3G people, or over 40 per cent of those attacked. Uebrie 3 reports briefly the clinical history of G cases of diphtheria which occurred in the garrison of Sebdou, and states that while the sixth case (2 were fatal) was still under treatment in the hospital 10 fowls kept in a house not far from the hospital were attacked with diphtheria, and exhibited symptoms strikingly like those present in the human beings. Five of the 10 fowls died, and two heads were sent to Arloing, who confirmed the diagnosis of fowl diphtheria. The fowls were fed by a hospital attendant, and it was ascertained that an identi- cal outbreak had occurred among the fowls at a neighboring place from which one of the 6 cases of human diphtheria had been brought. Debrie is inclined to the view that human diphtheria is transmissible to fowls and fowl diphtheria to man. 1 Revue oules. (See Fowl cholera. ) Coccidium ovi forme 9 tenellum 9 Coops, disinfection 26 Corrosive sublimate 26 Councilman and Lafleur, investigations 20 Cover-glass preparations 54 Cushman, S., assistance 7 Dawson, C. F 22, 57, 66, 73 Diphtheria in fowls 39 conditions favorable 40 contagiousness 40 economic importance 40 epizootics 41 lesions 51, 52 methods of investigation 11 outbreaks investigated 42, 46, 49, 50 pathogenic bacillus associated with the lesions 42, 44, 45,47,48,49,53,55. 5ti prevention and treatment 58 relation to public health 60 saprophytic bacteria associated with 53 symptoms 40 Disease in pigeons 71 description of bacillus associated with 73 relation to Bacillus cholera; suis 73 economic importance 72 history • 71 symptoms 71 Epithelium, destruction 10 89 7+ 90 INDEX. Flagellate 21 Flagg, Professor, assistance 7 Fowl cholera 63 nature of inoculation disease 67 outbreaks 64, 65 pathogenic bacillus obtained from fowls 65 its relation to rabbit septicaemia and swine- plague bacilli 65, 69 Gallua domeslicus 42 Giant cells, appearance of parasites 17 Hawley, A. H., experiments in raising pigeons 71 Kilborue, F. L., examination of fowls 45 Kruse and Pasquale, investigations 20 Leucocy tosis 14, 67, 68 Megrims in pigeons 71, 75 Microparasites. (See Ainoeba meleagridis.) Molluscum contagio8um 18 Nonmotile bacillus in diphtheritic lesions of fowls. (See Diphtheria.) etiological relation to the disease 58 Mitoses 10 Pathogenic bacillus of the hog-cholera group. (See Disease in pigeons.) Pigeons, diseases, notes 71, 72, 73 Protozoan disease of turkey 7 analogy to amoebic dysentery 10 appearance of liver 11 changes of the liver 12 extent of ca?cal disease 16 liver disease 16 external appearance . r ■- 8 giant cells 11, 13 parasites in the liver 13 multiplication 13 relation of bacteria 11, 21 to certain other diseases of poultry 22 diseases of cseca in fowls 26 other ca?ea disease in turkeys 22 seat of disease 9 special characters 8 symptoms 8 treatment 26 von Ratz, S., investigations 23 Rhode Island Station - 7 Roup. (See Diphtheria. ) Salmon, D. E., results of investigations 63,68 Schroeder, E. C, experiments 46 Slaked lime . .' 27 Taeniasis in fowls 46 Toxic substance 51 Traumatism 41 Turkeys, diseases of. (See Protozoan disease. ) examination, history 27 tapeworms in 8 voluntary contributions 7 Vineland, N. J., epizootic diseases among pigeons 71 Warts 18 Wheeler, Professor, acknowledgments 7 ^* AY ^k 5?"% °^W .♦* <*> r oK ^tf 5 V - 1 • ' • ' 1 * **> -^IHI§^ a c' ^ °W^W* aV*^ -^H ^ «*■" o*«^^Pf« ^ r$ ' *<&M^*\ ^ ** o«v^uai'« ^ ^ ^o^ W ^ ^ W V v • ' ^o' 'bK v-6< **v ° ^Pt^. r >v • assist t v* v °^E!K r *•»** - ^ iPv\ "^