88 



HOG CHOLERA 



at the time it was killed, and that it shall be free 

 of other infectious diseases which may be trans- 

 mitted through its blood. The clinical history of 

 the pig, and more especially the autopsy, enables 

 us to select on this basis. If in addition to a clini- 



PLATE 9. Post-mortem room where autopsies on virus pigs are 

 held. Each pig must show marked lesions of acute hog cholera, 

 and must be free from other infectious diseases. (Courtesy 

 Pitman-Moore Biological Laboratories.) 



cal history suggesting hog cholera a pig shows 

 characteristic lesions of the disease, slight or se- 

 vere, in two or more organs, we consider the first 

 requirement satisfied. Generalized tuberculosis 

 disqualifies, but slight and localized tubercular le- 



