HOG CHOLERA: PREVENTION AND TREATMENT. 



7 



proper feeding tend to lower vitality and thus perhaps render ani- 

 mals more susceptible to disease, such conditions can not of them- 

 selves cause hog cholera. It can be produced only by the specific 

 microorganism referred to. 



SYMPTOMS SHOWN BY HOGS SICK WITH CHOLERA. 



The symptoms of hog cholera differ in different hogs and in differ- 

 ent herds, depending upon the strength of the germs and the resist- 

 ing power of the hogs. As a result of these variations the disease 

 has been said to exist in two forms, acute and chronic, though the 

 germ is the same in both. In the acute or severe type hogs sicken 

 and die quickly, so that farmers will say that a hog which is found 

 dead in the morning was well the night before. In the chronic or 

 less severe type hogs may be sick for weeks or months before they 

 succumb. 



When cholera begins in a herd the hogs do not all become sick 

 at once, but on the contrary only one or two will refuse to come up to 

 feed with the herd. They will remain hidden in the nest (fig. 3) 

 and when driven from the bed their backs may be arched and they 

 may appear cold and shiver. The balance of the herd may remain 



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Fig. 2. — Losses from hog cholera in the United States. 181)4-1917, inchiMv. 



