662 REPORT OP THE COMMISSIONER OF AGRICULTURE. 



The reaction is acid. Grown on gelatine a rather penetrating odor of decomposing 

 flesh is given off. Tlie bacterium of hog-cholera develojis no odor wliatever in 

 cultures. This microbe, therefore, resembled the bacterium of liog-colera very 

 closely in its microscopic characters, but differed froni it in some of its physiological 

 properties. This illustrates how important cultivation experiments are m the deter- 

 mination of specific differences. That it was not the bactca-ium of hog-cholera was 

 showTi by an utter want of pathogenic properties when inoculated into mice and 

 rabbits. Pigs were inoculated and fed; cultures were introduced per rectum without 

 any effect whatever. 



In one of the tubes the motile bacterium just described was mixed 

 with another microbe, which proved to be a very virulent germ. It 

 was obtained pure as follows: A rabbit inoculated with the mixture 

 from a liquid culture made from the original gelatine tube died in 

 seven days, after showing signs of lameness for several days. The 

 inoculated thigh was enlarged, the skin bluish. The subcutaneous 

 connective tissue was of a leathery consistency. The surface of the 

 muscular tissue on the inner aspect of the thigh was of a uniform 

 yellowish gray; this change extended into the muscular tissue to the 

 depth of o""" (one-eighth inch); the striated appearance was lost. 

 This change also involved the deeper intermuscular septa of the thigh. 

 On the abdomen the subcutis was infiltrated with a blood-stained 

 serum. The local effect had thus been unusuall)^ severe. Cultures 

 from the spleen, liver, and blood in gelatine tubes contained only 

 the second microbe. The one above described had no iDOwer of in- 

 vading the tissues of the rabit. That the microbe obtained from the 

 tissue of this rabbit was pathogenic the following experiments clearly 

 demonstrate: 



With pure liquid cultures of this microbe three mice were inocu- 

 lated. Two of these died within one and two days of inoculation. 

 In the spleen of both peculiar torula-like forms were found, presum- 

 ably the cocci in process of division, which was retarded by unfavor- 

 able conditions. Its effect upon a rabbit, however, was more pro- 

 nounced. This rabbit diecf three days after a hypodermic injection 

 of i'"' of a liquid culture. Beneath the skin of the inoculated thigh 

 there was a translucent gelatinous exudate about one-half inch 

 thick. The muscles of the thigh and of the contiguous wall of 

 the abdomen were dotted with closely set punctiform and larger ex- 

 travasations. In the abdomen they were very numerous on the large 

 intestine along a zone nearest the abdominal wall. They were also 

 found over the kidney and on the psoas muscle. Spleen not enlarged, 

 dark; liver rather pale; acini well marked; the entire right lung and 

 base of the left deeply congested; very few bacteria in the internal 

 organs. Two liquid cultures of blood and one from liver contained 

 the injected microbes. Gelatine cultures of blood, spleen, and liver 

 developed into numerous colonies of the same microbe in the needle 

 track. 



Two iDigs (Nos. 287 and 289) were inoculated September 11 from a 

 culture of the rabbit. Each received beneath the skin of the thigh 

 2^'^'' of the culture liquid. No. 287 became dull and lost its appetite 

 several days later; eyes discharging. September 28 the animal be- 

 came delirious and ran blindly about the pen; dead next morning. 

 The only observable lesions were local swellings two inch-^^ across and 

 one-fourth to three-fourths inch thick, with centers which were be- 

 ginning to soften. Blood very dark, not coagulated; a few petechise 

 on epicardium. The liver was very pale, sclerosed; the medulla of 

 kidney deeply reddened. No. 289 died September 21, after exhibiting 

 the same symptoms; local swellings as above, without indications of 



