Swine Groiuers* Session. 



113 



gilts were removed some distance from the grounds for further 

 protection. These were all inoculated with 40 c. c. of serum each. 

 These animals, however, did not escape opportunities for infection, 

 since the same attendant who cared for the sick farm hogs, also 

 fed and watered these. Moreover some of these gilts were driven 

 over the infected grounds to the pens of the boars mentioned above 

 for breeding. During this time a number of hogs that were not 

 injected with the serum died from cholera. Our observations show 

 that the serum is not effective when inoculated into an animal which 

 is showing symptoms of the disease, but it shows a very high pro- 

 tective value in preventing the development of the disease. 



Fig. 6. Disinfecting the tail preparatory to drawing blood. 



A further test of the serum from the hog made "hyper- 

 immune" by feeding diseased viscera was also made upon three 

 other lots of hogs on the State farm. In one lot, No. 5, consisting 

 of four Duroc gilts weighing about 150 pounds each, two were in- 

 oculated with 40 c. c. each of clear serum, and at the same time 

 were inoculated with 2 c. c. of virulent blood from one of the check 

 pigs that had died in lot 4 already mentioned. Two more were 

 inoculated with the blood corpuscles tolerably free from serum, in 

 doses of 40 c. c. each. These were also inoculated with 2 c. c. of 

 the same virulent blood. One check animal of the same litter was 

 not inoculated. All of these animals contracted the disease, and 

 all but one died. The post-mortems showed evidences of a very 

 acute septicemia, corresponding to the haemorrhagic type of hog 



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