228 DISEASES OF SWINE 



these disease-producing germs may not be able to directly repro- 

 duce the same disease in the hogs which eat the dead body of the 

 animal in which they have produced death, but they are capable of 

 setting up stomach and bowel disturbances which will so lower the 

 resistance of the animals that they very readily fall victims to an 

 attack of cholera if they become exposed in any manner to the 

 germs of the disease. 



Some two or three years ago I met with an outbreak of cholera 

 which was brought about in the following manner: The feeder 

 was one of the large stockmen of the Central West. He had a large 

 herd of cattle, and following these cattle in the pens he had a 

 drove of several hundred young shoats, averaging, perhaps, 100 

 pounds each. 



Early in the winter he began to feed silage to the cattle from a 

 new silo which had been put up during the summer. For some 

 reason or other the silage had undergone a fermentative change, 

 and had developed a ptomain or poison of some sort which proved 

 extremely poisonous to the cattle. They began to show signs of 

 poisoning, indigestion, diarrhea, high temperature, and one or two 

 of them died in the course of a few days. These dead cattle were 

 left lying where they died in the pens and were soon cleaned up by 

 the greedy hogs. 



. Several of the hogs developed an attack of scours after eating 

 these carcasses, but they soon recovered, and were apparently as 

 well as ever. About a week later three more of the cattle were 

 found to be sick, and as there was a local veterinary surgeon vac- 

 cinating a herd of hogs about a mile and a half distant he was 

 called up and requested to stop at the farm on his way back to 

 town. 



This he did, and went out into the feed lots to examine the sick 

 cattle, having come directly from the farm where he had done the 

 vaccinating. The hogs on this farm had already developed cholera, 

 several had died, and a large number had a high temperature. He 

 soon determined the cause of the trouble in the cattle, and recom- 

 mended that the feeding of the silage be discontinued. This was 

 done, and the disease affecting the cattle quickly disappeared. 



About two weeks later, however, several of the hogs were 

 noticed to be ailing, and in a few days were dying at a rapid rate. 



