414 



STATE BOARD OF AGRICULTURE. 



Of the 56 samples of virus blood tested, 



7 or 12.5 per cent gave no reaction at a dilution of 1 — 50. 



4 or 7 1-7 per cent gave a reaction at a dilution of 1 — 50. 



3 or 5 5-14 per cent gave a reaction at a dilution of 1 — 100. 



6 or 10 5-7 per cent gave a reaction at a dilution of 1 — 125. 



12 or 21 3-7 per cent gave a reaction at a dilution of 1 — 250. 



21 or 37.5 per cent gave a reaction at a dilution of 1 — 500. 



3 or 5 5-14 per cent gave a reaction at a dilution of 1 — 800. 



It is readily apparent that the blood of pigs treated with hog cholera 

 viras acquires agghitinin for B. cholerae suis considerably in ex- 

 cess of that found in normal serum. For, whereas only 6i/4 per cent 

 of the samples of normal serum agglutinated at a dilution of 1-250, 

 64 2-7 per cent of the samples of virus blood agglutinated at a dilu- 

 tion of 1-250 or above. 



In studying the influence of body weight* upon the agglutinin content 

 of the blood of hog cholera pig's, we get results similar to those re- 

 corded under normal serum. 



The average weight of 



7 pigs 

 4 pigs 

 3 pigs 

 6 pigs 

 12 pigs 

 21 pigs 

 3 pigs 



whose blood did not react at 1 — 50 is 37 lbs. 



50 is 63 lbs. 

 100 is 90 lbs. 

 125 is 83 lbs. 

 250 is 55 

 500 is 66 



v^hose 

 whose 

 whose 

 whose 

 whose 

 whose 



blood 

 blood 

 blood 

 blood 

 blood 

 blood 



reacted at 

 reacted at 

 reacted at 

 reacted at 

 reacted at 

 reacted at 



1- 

 1- 

 1- 

 1- 

 1- 

 1- 



Ibs. 

 lbs. 



-800 is 95 lbs. 



It must be admitted that the relation between weight and agglutiua- 



Sfe' 



tive power of serum is only suggested by these figures. We do not 

 wish to make any generalization yet. 



The next factor to be considered that may influence the agglutina- 

 tive power of the virus blood is the treatment, in other words, the 

 amount of infective blood injected into the pig. The following summary 

 shows the relation between the quantity of virus injected, the aver- 

 age weight of the pigs treated and the average of the agglutination maxi- 

 mums. 



*Which is in a general way equivalent to age in the pigs here considered. 



