170 LOUIS PASTEUR 



or move about in a sluggish manner are the char- 

 acteristic symptoms of this malady which often 

 carries off ninety percent of the infected brood. 

 The few which recover seem to be immune to fu- 

 ture attacks. The disease is highly contagious and 

 may be conveyed by food contaminated with the 

 excreta of infected birds. 



Very minute bodies described as "granulations" 

 had been observed by Moritz in the blood of 

 chickens suffering from cholera. Are they the 

 cause of the disease? Toussaint, who had brought 

 forth evidence of the causal role of these organisms 

 had made rather unsuccessful attempts to cultivate 

 them. Pasteur, after having tried a number of cul- 

 ture media which proved unsuitable, discovered that 

 in a sterilized broth made of chicken gristle the 

 organisms would multiply with almost incredible 

 rapidity. Successive cultures were made, the one 

 from the other. Fowl inoculated with these 

 speedily contracted the disease. Pasteur found 

 that chicken cholera, like anthrax, affects different 

 animals in different ways. Rabbits are quite sus- 

 ceptible, but guinea pigs are much less so ; the in- 

 oculations producing only a local abscess, in which, 

 however, the germs multiply and from which they 

 may be recovered and inoculated again into fowl 



