PRACTICE OF MEDICINE AND HYGIENE 



ant food recovered with but slight traces of the 

 disease at the site of inoculation. 



When a surgeon has under observation a 

 questionable case of tuberculosis, the diagnosis 

 can be determined by inoculating a guinea pig 

 with some of the products of the lesion. If it is 

 tuberculosis the animal rapidly develops the 

 disease. Many hospitals keep guinea pigs for 

 this purpose, and the service which the little 

 animals thus render to man is considerable. 

 Tuberculin is also used for diagnostic purposes. 

 One of the important investigations now in 

 progress is that which has in view the determi- 

 nation of the relation between human and 

 bovine tuberculosis. Can we and our children 

 contract tuberculosis from the flesh and milk 

 of tuberculous cows? The similarity or dis- 

 similarity of these two forms of tuberculosis 

 cannot be discovered without making scientific 

 studies of the living animals and without sacri- 

 ficing some of these animals in these studies. 

 By the use of the products of the tubercle 

 bacillus, injected into suspected cows, it is de- 

 termined whether the animals have tubercu- 

 losis or not; and thus the danger of infection 

 through milk is greatly reduced. 



Experimentation is also being conducted 



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