PREDISPOSING CAUSES 



105 



An example of how these hog wallows are capable of harboring 

 infection is to be seen in the following instance : 



An outbreak of cholera occurred in the early spring on a farm 

 in central Nebraska. The feed lot in which the animals had 

 range was provided with a large pond or wallow, about 100 feet 

 long by 50 feet wide. This pond usually contained about a 

 foot of mud in the bottom and a Hke amount of water. During 

 the outbreak of cholera on the premises the hogs affected by the 



Fig. 41.- 



-Hogs kept in an insanitary feed lot; such conditions are an open 

 invitation to cholera. (B. A. I. Circular, No. 201.) 



disease were very prone to seek rehef from their feverish condition 

 by burrowing in the cooling waters of the pond. The outbreak 

 finally swept the pens clear, and not a hog was on the premises 

 from June 1st to the latter part of December. 



After the outbreak had rid the premises of hogs, the owner 

 raked up all the loose cobs and other trash on the ground and a 

 part of it was burned. The balance was thrown into the pond for 

 the purpose of partly filling it up. The ground was then spread over 

 with a thin layer of straw and over this kerosene was Uberally 



