﻿EXPERIMENTS ON THE CULTIVATION OF RINDERPEST VIRUS 

 AS DESCRIBED BY BALDREY 



By William Hutchins Boynton 

 {From the Veterinary Division, Bureau of Agriculture, Manila, P. I.) 



Baldrey ' states that he was able to produce material highly- 

 toxic for cattle by inoculating broth culture medium with virulent 

 blood and allowing it to incubate at 37° C. for twenty-four hours. 



Baldrey conducted his work in accordance with the presump- 

 tion that rinderpest serum is an antitoxin and that by injecting 

 the toxin obtained by cultural methods, in place of virulent, 

 blood, an antitoxic serum could be obtained. In the preliminary 

 work, defibrinated virulent blood was inoculated into ordinary 

 broth in flasks of 500 cubic centimeters' capacity in the propor- 

 tion of 50 cubic centimeters of blood to 950 cubic centimeters 

 of broth. The medium was incubated at 37° C. for twenty-four 

 hours. Six immunized animals were injected subcutaneously 

 with this, in doses varying from 300 to 700 cubic centimeters. 

 Four of these died in from twenty to twenty-four hours, and the 

 remaining two were destroyed as a result of the extensive gan- 

 grene set up at the seat of inoculation. The post-mortem exam- 

 inations revealed evidence of acute toxaemia. 



Three animals formerly used for serum production were 

 employed to test the possibility of hyperimmunizing animals 

 with culture medium and virulent blood after incubation. Mar- 

 tin's broth was employed, but the relative amounts of culture 

 medium and defibrinated virulent blood remained as in the first 

 experiment. The immunizing properties of the sera produced 

 by this method were tested in comparison with other sera. 



Baldrey draws the following conclusions from his experi- 

 ments : 



1. That Anti-Rinderpest Serum can be prepared by the inoculation of 

 virulent blood diluted with broth. 



2. It appears possible that an active toxin is produced and excreted into 

 the Broth by the Rinderpest organisms contained in the virulent Blood and 

 by this means the results recorded are obtained. 



3. This material or probable toxin is rapidly excreted and so active that 

 it appears to quickly inhibit any further growth of the Rinderpest organism, 

 destroying its virulence and finally killing it. 



^Joum, Trap. Vet. Sci. (1911), 6, 251. 



259 



