176 



STATE BOARD OF AGRICULTURE. 



This hyiKii'immune was bled 4 times, iiieludiii^ killinj?, a total of 

 4435 cc. of serum being secured, which was tested as follows: 



SUMMAUY. 



It is impossible at present to state just how salt solution gains its 

 virulence when injected into the abdomen of virus pigs and knowing very 

 little of this ultra-microscopic virus causing hog cholera, it is impossible 

 to determine just how virulent this solution may get. The vinilcnco no 

 doubt varies greatly with dillerent ])igs even though autoj^^ies corresp<jnd. 

 As well as gaining virulence by taking up this virus from organs and 

 abdominal walls by contact and by growth, it seems that this solution is 

 subjected to osmosis which probably increases its vinilence. As far as 

 our methods of standardizing virus go, we fail to see a decrease in 

 virulence of virus blood due to injecting salt solution, although the virus 

 blood is considerably increased by the injection. 



It is generally admitted by serum manufacturers Ihat the amount of 

 virus blood secured from vims pigs averages about 10 cubic centimeters 

 per pound of body weight. Accepting this as a standard, I have en- 

 deavored to calculate the per cent of increase of virulent material secured 

 when salt solution Avas injected intra-abdominally as follows: 



