138 HOG CHOLERA 



method consists of giving serum in exactly the 

 same manner as has already been described, and 

 of administering at the same time, and with a 

 separate syringe, the required dose of hog cholera 

 virus. Usually the dose of serum is given in one 

 of the sites of injection already mentioned, and 

 the virus at the corresponding point on the oppo- 

 site side. The technique of administering virus 

 does not differ from that employed with serum, 

 except that special care is required in disinfecting 

 the site of injection after the needle is removed. 

 Also the dose of virus is so small that massage is 

 not required. No virus should be allowed to drop 

 on the ground, and all that is not used should be 

 burned. 



Simultaneous treatment possesses the great ad- 

 vantage of producing a permanent immunity in all 

 swine that are more than twelve weeks old, and in 

 many of those that are younger. On the other 

 hand it involves the use of a lethal dose of hog 

 cholera virus, thus producing certain sequelae and 

 adding specific dangers that are not associated 

 with serum alone treatment. 



Dosage of serum and virus. The same princi- 

 ples that apply to dosage of serum administered 

 alone, apply when it is given with virus. We give 

 at least as much serum as the label indicates, in- 

 creasing the dose when we are compelled to ad- 

 minister simultaneous treatment to hogs below 



