PREDISPOSING CAUSES 117 



that they keep everybody out of their hog pastures, and do not 

 allow their hogs to run in a field adjoining the hog lots or pastures 

 of their neighbors. 



I have often heard it remarked in different localities that 

 "Old Squire Jones" never loses any hogs with the cholera, because 

 he is such a cranky old crab that cholera would not go near him. 

 In most cases this "Old Squire" is just enough of a crank that he 

 won't allow any stranger to enter the pens where his hogs are feed- 

 ing, and kills any stray dogs that he may find frequenting his place. 

 The result is that he places a barrier to the entrance of cholera upon 

 his premises, and his hogs escape, while those of his neighbor are 

 dying by hundreds. 



(16) Newly Purchased Hogs. — Every farmer should make it a 

 rule never to add any newly purchased animals of any kind to his 

 regular herds or stables until they have been isolated for at least 

 thirty days, and closely watched for symptoms of any disease which 

 might be transmitted to the regular stock on the place. This is 

 a rule that may be very profitably followed, not only with respect 

 to hogs, but also with regards to cattle, horses, and sheep as well. 

 A regular pen, paddock, or stable should be provided for this pur- 

 pose, and used whenever any new live stock of any kind is brought 

 on to the farm. 



During the winter months hogs are often purchased for breed- 

 ing purposes at public sales, or from some other farm miles distant, 

 and brought to the home farm and placed immediately in contact 

 with other animals of the herd. These newly introduced swine 

 may have been recently exposed to cholera, and, if so, will develop 

 the disease in the course of a couple of weeks, and spread the dis- 

 ease to the entire herd. 



On the other hand, the newly purchased animals may be them- 

 selves free from disease, but may have come from an infected feed 

 lot, and carry upon their feet infectious material which serves to 

 introduce the hog-cholera virus upon the farm. New purchases 

 should be put through a dipping tank before being admitted to the 

 feed yards or any regular pens. 



Not uncommonly the purchased animals will have recently 

 had an attack of cholera, but are now apparently getting well 

 again. These hogs, however, often discharge hog-cholera virus in 



