CHAPTER VI. 

 HOG-CHOLERA. 



Bacillus Suipestifer (Salmon and Smith 1 ). 



The bacillus of hog-cholera was first found by Salmon 

 and Smith, 1 but was for a long time confused with the 

 bacillus of "swine-plague," which it closely resembles 

 and with which it frequently occurs. It is a member of 

 the group of which the Bacillus coli communis may be 

 taken as a type. Since the careful studies of Smith, 1 

 however, the claims of the discoverers that the bacillus 

 of hog cholera is a separate and specific organism can 

 hardly be doubted. 



Hog-cholera, or "pig typhoid," as the English call it, 

 is a common epidemic disease of swine, which at times 

 kills 90 per cent, of the infected animals, and thus causes 

 immense loss to breeders. Salmon estimates that the 

 annual losses from this disease in the United States 

 range from $10,000,000 to $25,000,000. 



The disease is particularly fatal to young pigs. The 

 symptoms are not very characteristic, and the animals 

 often die suddenly without having appeared particularly 

 ill, or after seeming ill but a few hours. The symptoms 

 consist of fever (io6°-io7° F.), unwillingness to move, 

 and more or less loss of appetite. The animals may ap- 

 pear stupid and dull, and have a tendency to hide in the 

 bedding and remain covered by it. The bowels may be 

 normal or constipated at the beginning of the attack, 

 but later there is generally a liquid and fetid diarrhea, 

 abundant, exhausting, and persisting to the end. The 

 eyes are congested and watery, the secretion drying and 



1 Reports of the Bureau of Animal Industry, 1885-91. 



2 Centra/6/, fur Bait, und Parasitenk., Bd. ix., Nos. 8, 9, and 10, March 

 2, 1897. 



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