THE BACILLUS FOR SMALL ANIMALS 173 



tant part in determining the pathogenicity of the 

 bacillus and its distribution in the body of a naturally 

 affected animal. 



Since this book was written C. C. Twort has suc- 

 ceeded in reproducing in a rabbit a pathological condi- 

 tion similar to that found in cattle and sheep in the 

 early stages of Johne's disease. This he has done by 

 the intravenous inoculation of a culture of Johne's 

 bacillus which has become acclimatized to grow ^n 

 ordinary glycerine-beef broth. On post-mortem ex- 

 amination the mucous membrane in the vicinity of the 

 ileo-caecal valve was thickened, and the abdominal 

 lymphatic glands were large and oedematous ; bacilli 

 were found in both situations, and there was no 

 evidence of caseation. The disease in the intestine 

 did not extend more than a foot from the ileo-caecal 

 valve. It may be noted that the animal was inoculated 

 with two doses of Johne's bacillus. 



