PREPARATION OF ANTI-HOG-CHOLERA SERUM 83 



of virulent hog cholera blood. A slight reaction 

 follows, and in the course of a few days the im- 

 mune becomes a hyperimmune and comparatively 

 small doses of its blood will protect other hogs ex- 

 posed to cholera. 



We are now ready to consider in some detail the 

 various steps required in preparing anti-hog-chol- 

 era serum. In all these it is a principle that the 

 operating room shall be clean and free from dust, 

 that the floor shall be dampened, that the operator 

 shall wear clean clothing and that his hands shall 

 be scrupulously clean. The hands must not touch 

 the serum or virus blood, and all instruments and 

 containers with which the blood comes in contact 

 must be sterilized before use. Antiseptic solution 

 should be applied by means of a gravity irrigator 

 or some other device which prevents the hands 

 from passing alternately between operating field 

 and antiseptic container. Exact records of each 

 operation must be kept, and each hog used must 

 be identified with a number tag. 



Immunizing. Requirements. Two hypodermic 

 syringes, one ten mil capacity or less, for virus, 

 the other twenty mil capacity or more, for serum ; 

 scrub-brush and antiseptic solution, also anti-hog- 

 cholera serum and hog cholera virus each in a 

 separate, covered receptacle. 



The pig is held by an assistant and the skin 

 covering both armpits (or the inner region of both 



