DIFFEEENCE IN SUSCEPTIBILITY TO CATTLE PLAGUE. 429 



Table 5. , 



No. of animal. 



Quantity 

 of V. B. 



Quantity 

 of serum. 



Eesults. 



23 



24 



2.5 



26 



27 



cc. 

 0.5 

 .5 

 .5 

 .5 

 .5 



cc. 



None. 

 25 

 .50 

 75 

 100 



Died. 



Died. 



Lived. 



Lived. 



Lived. 



Table 5 shows the results obtained. Animals Nos. 33 and 24 died of 

 cattle plague, Nos. 25 to 27, inclusive, underwent good reactions but 

 recovered. (See charts 23 to 27.) 



Test 6. 



Early in August, 1909, Doctor Gearhardt, of the Bureau of Agricul- 

 ture, sent to the Biological Laboratory Bureau of Science several bottles 

 of foreign anticattle-plague serum, and requested that its immunizing 

 value be determined. According to directions on these bottles, 20 cubic 

 centimeters of the serum given by the simultaneous method should have 

 been sufficient to protect medium-sized animals against a fatal attack of 

 cattle plague. 



On the 15th day of August, five Batanes bullocks, Nos. 28 to 32, in- 

 clusive, were each inoculated with 0.5 cubic centimeter of virulent blood. 

 Animal No. 28 was used as control, Nos. 29 to 32, inclusive, received 

 25, 50, 75 and 100 cubic centimeters of foreign serum, respectively. 



Table 6. 



No. of animal. 



Q.uantity 

 of V. B. 



Quantity 

 of serum. 



Results. 



Died. 

 Died. 

 Died. 

 Died. 

 Died. 



28 



29 



cc. 

 0.5 

 .5 

 .5 

 .5 

 .5 



cc. 



None. 



25 



50 



75 



100 



30 - 



31 



32 





The results obtained with the foreign serum are recorded in Table 6. 

 All animals died of typical cattle plague despite the fact that animal 

 No. 32 had received ten times the prescribed dose of serum. (See 

 charts Nos. 28 to 32.) 



