82 REPORT OF THE BUREAU OF ANIMAL INDUSTRY. 



ceived at the same time one-ninth cubic centimeter subcntaneonsly 

 in the thigh. It died in five days. The spleen was much enlarged, 

 blackish, friable, and contained hog cholera bacteria. A roll cult- 

 ure contained numerous colonies after two days. 



No. 460 became very weak in its hind limbs in less than a week; 

 respiration short and quick; bowels relaxed. It was found dead on 

 the ninth day. 



Superficial inguinal glands normal. PetecchiaB in the slight deposit of fatty tissue 

 beneath peritoneum of abdominal muscles. Spleen about 12 inches long, 1 wide, 

 and three-fourths inch thick at the hilus," blackish, friable. A few petecchiae on cor- 

 tex of left kidney, one cyst the size of a large pea in medullary portion. Large 

 number of small hemorrhages in connective tissue around pelvis of right kidney. 

 Two small urinary cysts not showing on surface. Glands in lesser omentum en- 

 larged, hemorrhagic throughout. In caecum and colon an almost continuous yel- 

 low sheet of superficial necrosis about 1 millimeter thick covering the mucosa. 

 In lower colon it breaks up into isolated patches simulating ulcers. In microscopic 

 sections this layer is found to consist of necrosed epithelium with some round cells. 

 On Fevers patches, in lower ileum, a yellow, soft exudate rests, which is not adherent 

 and might be mistaken for chyle. Lobes of right lung glued together and to peri- 

 cardium. Pleura thickened generally, serum very slight in amount, blood-stained. 

 On lobes of left lung, which are also glued together, and on right lung there is a very 

 slight deposit about one-half millimeter thick in the form of a net-work. As a 

 rule the pleuritis and exudate are most marked on the most dependent portions of the 

 lungs. Cavity of pericardium normal. Lung tissue not hepatized anywhere; 

 trachea and bronchi contain a small quantity of reddish fluid. Bronchial glands 

 and those along posterior aorta hemorrhagic throughout. Cultures from pleura! 

 cavities, as well as those from spleen, contain only hog cholera bacteria. As shown 

 in roll cultures they were very numerous in the latter organ. 



While No. 460 presented such a well-marked case, No. 461, although presenting at 

 first the same symptoms, slowly recovered. The difference may have been due to 

 the fact that with No. 460 a 6-inch needle was used, while with 461 one only 3 inches 

 long. In the latter case the chance for the passage of bacteria into the lung tissue 

 and thence into the intestines was much poorer. 



Bacteriological observations. The preceding experiments on rab- 

 bits and the intra-thoracic inoculation in case of the pig are suffi- 

 cient of themselves to establish the fact that the bacteria described 

 in the two preceding reports, and again found in this epizootic, are 

 the cause of hog cholera. It may be added, however, that out of the 

 fifty-six cases (here reported) hog cholera bacteria were found in the 

 spleen of all but six cases. Even in these the cultures made were 

 too few to make the negative evidence of any value. 



In many cases the hog cholera bacteria were associated with a 

 rather large bacillus which, for the sake of convenience, may be called 

 butyric bacillus. This organism was only detected when a bit of 

 spleen was dropped into beef infusion with or without peptone. 

 The cultures kept at about 35 C. contained on the second or third 

 day a cloudy mass limited to the bottom of the tube. The cloud 

 was made up of bacilli, rather large, with a spore in one extremity of 

 the rod, strongly refracting the light. The rod was not enlarged at 

 this end in the fresh state. When dried ana stained, the shrunken 

 protoplasm gave the spore-bearing end a swollen appearance, re- 

 minding one of the tailed bacteria of older writers. In the few 

 tubes in which this bacillus alone was present the liquid itself re- 

 mained perfectly clear ; when hog cholera bacteria were present it 

 became uniformly but faintly clouded. In liquid cultures without 

 the bit of spleen the bacilli did not develop. This was evidently 

 necessary as food material. In gelatine tubes and roll cultures the 

 bacilli did not grow. Any pathogenic activity can not be ascribed 

 to them. They are anaerobic organisms, probably abundant in the 

 alimentary tract, which were absorbed from ulcers or hemorrhages 



