BUREAU OF AXIMAL IXDUSTRY. 487 



were the starting-point of au outbreak at the experimental station, 

 wliicb has finally enabled us to demonstrate as the cause of the disease 

 a sjiecilic microbe. This outbreak was characterized by great %irulcnce, 

 and most of the infected animals died in the early stages of the disease. 



These two animals, when bronght to the station November 4, ex- 

 liibited the usual symptoms of swine pla;:ue, great depression, with pro- 

 liise diarrhea. The owner stated that they had been sick for abont a 

 week. On the following day one (Xo. 105), was so low (temperature, 

 {)~P F.) that we decided to kill it, the warm weather not ])romising good 

 preservation if it should die in the night. It was killed by a blow on 

 tiic head. The skin was slightly bluish in the axilla, a similar bat less 

 marked discoloration on the abdomen. The superficial inguinal glands 

 were gi'eatly enlarged, the individual lobules standing out prominently, 

 some of a pale flesh-color, others purplish, medulla pale. In opening . 

 tlic abdomen a few whitish patches were observed on the small intes- 

 tine, correspondins," to ulcerations, as determined later. 



There was a moderate quantity of watery serum in both pleural sacs. 

 The lungs were normal, with the exception of a small anterior lobe on 

 each side which was hepatized. The pericardium was slightly dis- 

 tended with a colorless fluid ; a small clot in each ventricle. Very severe 

 lesions were found in the intestinal tract. The partially-empty stomach 

 contained two coiled up specimens of ascaris. The pale mucosa was 

 studded with several isolated yellowish ulcers, about one-fourth of an 

 inch in diameter, raised above the surface and flattened at the top. In 

 the ileum extensive ulcerations were found, extending for a distance of 

 about 2 feet from the valve. These ulcers had a depressed base, as if the 

 tissue had been dug away, and were surrounded by a smooth elevated 

 border. In the caecum and large intestine in general, the ulcerations 

 were very numerous, varying from one-eighth to one-third of an inch in 

 diameter. The smallest ones appeared as yellowish specks. The larg- 

 est ones were slightly depressed, containing black, ragged, necrotic 

 masses. The lymphatics, at the root of the mesentery and near ! he ileo- 

 ca^cal valve, were greatly enlarged, representing a continuous cylindrical 

 ma<:s, at least an inch thick, and varying from a pale flesh-color to a 

 dark red. 



This was evidently a severe case of swine plague, and one which, from 

 l>reviou.s experience, would ])rove unsatisfactory for purposes of inves- 

 tigation. Three cover-glnss preparations from the spleen, one from the 

 liver, two each from the hepatized lung tissue, and blood from the heart, 

 were searched with negative results. No bacteria could be seen. A 

 culti\i-e in a tube of nutritive gelatine rapidly liquefied the gelatine in 

 the track of the needle. Several kinds of bacteria were present, includ- 

 ing a chromogenous bacillus, described as bacillus lufeuft suis in the Sec- 

 ond Annual Keport of the liur.'tui. This sismc baeiihis was also present 

 among otherforms in a iicjuid ciiUare inoculated diiectly with blood from 

 the heart. 



Liquid cultures were made by inoculating sterile nutritive media with 

 a platinum wire dipped into tiie parenchyma of the spleen and liver, 

 exi)Osed by a cut with a flamed knife. Both contained a motile bac- 

 terium identified latei- as the bacterium of swine plague. AVhen line 

 cultures were made on gelatine, that of spleen was obviously pure ; the 

 colonies from the eull me of liver were of two kinds — one, the bacterium 

 of swine plague pro}>er, as determined later ; the other growing in colo- 

 nies ha\itig only one-fifth the bnear dimensions of the former. A liquid 

 culture, prepared by rubbing the platinum wire over the peritoneum, 

 contained, when tested by the above method, the swine plaaue bacte- 



