CHAPTER VI. 

 HOG-CHOLERA. 



THE bacillus of hog-cholera (Bacillus suipestifer) 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 u 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 ^ 188591. 



z Centralbl. fur Bakt. und Parasitenk., Bd. ix., Nos. 8, 9, and 10, March 

 2, 1897. 



413 



