BUKEAU OF ANIMAL INDUSTRY. 



639 



in this pen. The two check animals died on the Mth and 19th of 

 April, respectively. Of four vaccinated animals only No. 163 showed 

 signs of the disease, and gradually developed into a chronic case, dy- 

 ing of general debility on May 1. Tlie three other vaccinated ani- 

 mals remained apparently well for months after, although constantly 

 exposed to the disease in the infected pen. 



Autopsy notes. — No. 163. Spleen not much enlarged; textm-e fii-m; effusion into 

 pericardial and thoracic cavity. Lymphatic glands enlarged, but pale; two ulcers 

 in stomach; small intestine normal; mucosa of ceecum and colon studded with 

 many extensive and deep, yello^Ti3h ulcerations. On cover-glass preparations of 

 the spleen only a few bacteria could be seen. Two hquid cultui-es inoculated from 

 the same organ remained sterile. No colonies appeared in the gelatine tube inocu- 

 lated with blood from the heart. A few developed in the tulje inoculated from the 

 spleen. 



No. 195. Spleen greatly enlarged: gorged with blood; very friable; shi-eds of 

 a fibrinous exudate on serosa of intestines ; much serum in abdominal cavity ; i^ete- 

 chiae on efjicardium of auricles; small anterior lobes of lung hepatized; mucous 

 membrane of gall bladder ulcerated; extensive ulceration and inflammation of mu- 

 cous membrane of cajcum and colon. Hemorrhagic inflammation of kidneys. 



No. 201. Spleen but shghtly enlarged; lungs extensively hepatized; intense con- 

 gestion and commencing ulceration of the mucosa of large intestine; stomach and 

 portion of ileum similarly congested. Though no bacteria were found on a cover- 

 glass preparation, a pure culture was obtained by carefully dropping a piece of 

 spleen tissue into a culture tube. This was tested on gelatine. 



After apparently resisting the infection for several months the remaming pigs' 

 (Nos. 164, 177, and 196) were transferred to a clean pen. No. 177, not very thrifty, 

 began to decline, and finally died July 23. Ajnong the most prominent lesions were 

 a plastic exudate on the epicardium and numerous large old ulcers in the large in- 

 testine. The mucosa itself was extensively pigmented. No. 196, on removal from 

 the infected pen, seemed in good condition, but it died July 7, after some days of 

 untlirifty condition. In this case the mucous membrane of the large intestine was 

 pigmented, and there were what appeared to be cicatrices of old ulcerations. In all 

 of the large serous cavities there was considerable effusion. In cover-glass prepa- 

 rations of the spleen there were no hog-cholera bacteria to be seen, but numerous 

 bacilli resembling those of malignant oedema. 



A second experiment was made in the same way upon Nos. 197 to 

 200, inclusive, and JSTo. 157. March 24 each animal received in the 

 thigh about 10'=*' of a mixture of heated cultures in beef infusion with 

 1 per cent, peptone about fourteen days old. March 29 an equal 

 amount was injected, one-half into each axilla, these cultures being 

 about fifteen days old. These animals were kept until April 20, when 

 all but No. 157 were placed in the large infected pen. From that 

 date on pigs died almost every day of the disease, so that the infection 

 must have been quite thorough. Unfortunately no check animal 

 was exposed at the same time. In these animals the slight swelling 

 at the seat of inoculation disappeared in a few weeks. 



They remained well, with the exception of No. 199, which became 

 emaciated and was found dead May 19, about one month after expos- 



