56 HOG CHOLERA 



cum and upper colon, and as would be expected, 

 we find the secondary lesions distributed in pre- 

 cisely the same manner. If we examine a hog 

 dead of cholera after a short sickness we encoun- 

 ter intestinal lesions in which congestion, hemor- 

 rhages and early evidences of degeneration pre- 

 dominate. In hogs that have been sick longer, 

 autopsies often reveal a surprising variety of le- 

 sions which collectively encompass effects of the 

 struggle between degenerative and regenerative 

 forces, and which reach their most typical form in 

 the "button ulcer. " 



In considering thoracic lesions, the same general 

 principles apply. If we inject a pig with filtered 

 hog cholera virus, and kill it about seven days 

 later, the lungs, if affected, will show petechiae 

 and ecchymoses, most likely appearing on the 

 cephalic and cardiac lobes, but not always confined 

 to these parts. There may also be congestion of 

 the mucosa of the air passages. Both changes 

 are due to the filterable virus. What result 

 would we expect if a secondary invader, capable 

 of producing inflammatory changes, should find 

 its way into lesions thus prepared? Obviously we 

 would expect to find bronchopneumonia, occurring 

 most regularly in the cephalic and cardiac lobes 

 but not always thus limited. It is significant that 

 this is the exact picture presented when secondary 

 infection with Bact. suisepticum takes place. 



