198 DISEASES OF SWINE 



One of the worst outbreaks of cholera that I have ever seen 

 was spread through the agency of a running stream. Early in 

 the spring a farmer living along the banks of this small creek pur- 

 chased some hogs at a pubhc sale. These were immediately added 

 to his regular herd, as they were apparently in good health. 

 About three weeks later several of the animals of the regular herd 

 became sick and in a few days began to die. The course of the 

 disease was rather of the subacute variety, but postmortem find- 

 ings were unquestionably those of cholera. 



As this was a very busy season of the year, the owner was 

 rather careless in the disposal of the dead animals, and, as a result, 

 several of them were left lying in the field where the bodies were 

 devoured by other animals and by a large flock of buzzards which 

 were attracted by the opportunity for a feast. The pasture in 

 which the animals were kept was crossed by this small stream, and 

 a rain which fell about this time washed large amounts of infectious 

 material into the creek. 



Lower down in its course this stream passed through a number 

 of other pastures, and in the course of two weeks' time animals on 

 the farms down stream began to exhibit evidences of cholera. 

 Within a month there was a widespread outbreak of cholera, in- 

 volving the herds for miles down the stream. Several nighboring 

 farms, located back from the creek banks, were infected by the 

 buzzards which were attracted to the locality by the exposed dead 

 animal carcasses. 



This outbreak illustrates several points in the prevention of 

 cholera. In the first place, it shows the danger of adding new 

 hogs to the herd without first properly quarantining them for 

 at least thirty days to see if they are free from hog-cholera or other 

 disease transmissible to other animals. 



Second, it illustrates the danger of allowing hogs to range in 

 pastures which are crossed by a running stream, and especially so 

 if this stream receives drainage from other hog lots higher up in its 

 course, and they nearly all do. This is a danger which cannot 

 be overlooked, as running streams may carry the infection for 

 several miles and infect hogs in pastures at a great distance. 



This outbreak also illustrates another danger in the spread 

 of cholera. This is the effect of leaving dead carcasses exposed in 



