MILK-BORNE INFECTIOUS 



453 



weather, fatigue, use of cold drinking-water, etc. 

 method is abo used occasionally, and has the 



The 



ocular 

 over 



192. A 



Bd. No. 199, TV*. 



other methods in that the observer can compare the normal, 

 untreated eye with the eye receiving the tuberculin treatment. 



Fig. : B 



of iiijeitiBR toberarfm. 

 199,Unhr of 



BdL XOL 



Tne diagnostic value of tuberculin is varioudy stated to be 

 95 to 98 per cent, correct. There are several limitations to the 

 test. When the disease has reached the last staees animals mav 



