HEMORRHAGIC SEPTICEMIA GROUP 295 



B. Hemorrhagic septicemia of rodents transmissible to man: 

 Bacillus pestis. 



Bacillus avisepticus 



Synonyms. Bacillus cholera gallinarum; B. choleras; Bacterium 

 avicidum. 



Disease Produced. Fowl or chicken cholera in domestic fowls 

 and other birds. 



Perroncito, in 1878, first observed this organism in an outbreak 

 of chicken cholera. Pasteur, in 1880, cultivated the organism 

 and studied it quite at length. It was with this organism that he 

 performed his first experiments upon vaccination and the prepara- 

 tion of attenuated cultures. It is, therefore, of considerable 

 historic interest, as marking the 

 beginning of the experimental 

 study of immunity. 



Distribution. The disease is 

 known to occur in various Euro- 

 pean countries, and has been 

 reported from Canada and the 

 United States. 



Morphology and Staining. 

 B. avisepticus is a typical 

 member of the hemorrhagic 

 septicemia group; the char- 

 acters given under the intro- 



Fig. 119. Bacillus avisepticus, from 



ductory heading will serve for a n agar slant (X 1000) (Guntherj. 

 this form. 



Isolation and Culture. The organism may be isolated in pure 

 culture from the blood and internal organs of infected birds. The 

 colonies upon gelatin plates are small, white, usually irregular 

 dots, without marked or distinctive characters. In gelatin stab, 

 growth occurs along the line of inoculation in the form of numerous 

 tiny, discrete colonies, and upon the surface a thick mass generally 

 forms, rather circumscribed, giving to the whole the appearance 

 of a nail. Agar and blood-serum slants show a moderately luxur- 

 iant, white, glistening growth. Bouillon is slightly clouded. 



Physiologic Characters. B. avisepticus is aerobic and faculta- 

 tive anaerobic. It grows best at blood-heat, but will develop 



