CHAPTER VII 



PREPARATION OF ANTI-HOG-CHOLERA SERUM AND HOG 

 CHOLERA VIRUS 



WE are indebted to Dr. Marion Dorset and Dr. 

 W. B. Niles of the United States Bureau of Ani- 

 mal Industry for developing our present method 

 of preparing anti-hog-cholera serum. The dis- 

 covery that hog cholera is caused by a filterable 

 virus dismissed further efforts to immunize 

 against it with products of various bacteria, but 

 it suggested hope for a protective serum analo- 

 gous to that used against rinderpest, a filterable 

 virus disease of cattle. That hope was realized 

 in 1908 when Dorset announced his discovery, and 

 although the immediate control of hog cholera 

 which some predicted did not materialize, the ob- 

 stacles encountered have not been due to any fun- 

 damental defect in the serum itself. When prop- 

 erly prepared and used it is one of the most effec- 

 tive biologies known to preventive medicine. 



Anti-hog-cholera serum production is highly or- 

 ganized and carefully controlled in the United 

 States and many laboratories are in operation 

 which are models for convenience, cleanliness and 



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