CHAPTEK XXXI. 



PSEUDOTUBERCULOSIS AND ACID-FAST BACILLI OTHER THAN 



THE TUBERCLE BACILLUS RAT LEPROSY CHRONIC 



BACTERIAL DYSENTERY (JOHNE'S 



DISEASE) IN CATTLE. 



Pseudotuberculosis. When, after the discovery of the tubercle 

 bacillus, numerous investigators inoculated tubercular material, or 

 what appeared to be such, into laboratory animals it was ascertained 

 that these sometimes developed lesions which on first sight appeared 

 to be tubercular, but which on careful examination were found not to 

 contain the tubercle bacillus but other microorganisms. Observations 

 of this kind multiplied, and it has become customary to classify 

 such pseudotubercular pathologic changes due not to tubercle bacilli, 

 but to entirely different organism as pseudo tuberculoses. It was 

 further found that such pseudotubercular infections occurred not only 

 after artificial inoculations, but also spontaneously as laboratory 

 epizootics or among domestic and wild animals. 



Preisz, after having discovered a bacterium of this kind, and after 

 reviewing the work of others in this field, divided the bacillary pseudo- 

 tuberculoses into the three following groups based upon the causative 

 microorganisms : 



I. Pseudotuberculoses due to the Bacillus pseudotuberculosis 

 rodentium (rodents) of Pfeiffer, also called the Streptobacillus pseudo- 

 tuberculosis of Dor. 



II. Pseudotuberculoses due to the Bacillus pseudotuberculosis 

 murium (mice) of Kutscher. 



III. Pseudotuberculoses due to the Bacillus pseudotuberculosis ovis 

 (sheep) of Preisz. 



BACILLUS PSEUDOTUBERCULOSIS RODENTIUM. 



Occurrence. The bacillus causing pseudotuberculosis in rodents 

 is evidently a saprophyte encountered extensively in the outside 

 world. It has been found in garden earth, the sediments from rivers, 

 contaminated by sewage, dust, fodder, milk, etc. It apparently 

 becomes pathogenic occasionally, and then causes pseudotubercular 

 lesions in rabbits, hares, cats, chickens, pigeons, and even in cattle, 

 swine, and other animals. 



Pathologic Lesions. The pathologic lesions which lead, as a rule, 

 to progressive emaciation and finally death, are preferably found 



