MODES OF TUBERCULAR INFECTION IN 

 WILD ANIMALS IN CAPTIVITY. 



By W. REID BLAIR, D.V.S. 



IN the absence of the more positive information which one 

 acquires from a long series of experiments designed for the 

 purpose of ascertaining the priority and manner of invasion of 

 tuberculosis, much of this information regarding the progress 

 of the lesions has been gathered from post-mortem examinations 

 of natural cases. This is particularly the case in animals whose 

 price has prevented them from figuring largely in experimental 

 pathology. 



As the existence of tuberculosis is determined by the pres- 

 ence of tubercle bacillus which produces the disease, conse- 

 quently it is only since the characters of this were made known 

 that we have been able to make an absolute diagnosis in suspected 

 cases. 



The identity of tuberculosis in human beings and that of cer- 

 tain animals, and the possibility of one infecting the other, renders 

 this disease of the greatest importance. 



The great difficulty in determining when the animal first 

 becomes tuberculous makes it practically impossible to prevent 

 the possibility of infection to its companions. Particularly is 

 this danger greater among primates, where it is necessary to 

 confine from 6 to lo, or even more, in one cage. 



ANIMALS AFFECTED. 



While it is quite safe to say that hardly any animal possesses 

 absolute immunity from tuberculosis, certain species and indi- 

 viduals are undoubtedly less susceptible than others. 



My investigations from necessity have been confined to the 

 animals in the primate collection, owing to the fact that with 

 one or two exceptions the animals in the Park outside the pri- 



