BACILLUS OF FOWL CHOLERA 183 



Bouillon is slightly clouded. 



Milk is gradually coagulated by the formation of an acid. 



Litmus is reduced. Indol and Phenol are formed. 



Pathogenesis. The bacilli cause a typical septicaemia in small 

 doses by cutaneous inoculation (and in larger doses by feeding Giinther) 

 in pigeons, fowls, geese, ducks, pheasants, small birds, also birds of prey, 

 rabbits, and mice. Guinea-pigs, sheep, and horses exhibit only a local 

 reaction ; suppuration at the point of inoculation. Dogs and cats can 

 consume large quantities of the cadavers of infected animals without 

 becoming sick. Man can also tolerate infected meat. 



The bacilli are present in enormous quantities in the bloodvessels of 

 affected animals. In pigeons, and especially in chickens, the point of 

 inoculation is greatly inflamed, tending to necrosis. In the intestines a 

 hsemorrhagic enteritis occurs. Chickens and rabbits exhibit pneumonic 

 lesions. Pericarditis and haemorrhages on the pericardium are common. 

 The spleen and liver are also enlarged. The bacilli of fowl cholera pass 

 from the mother to the foetus that is, to the eggs. 



Immunity. Pasteur found that artificial cultures of fowl cholera 

 bacilli, if left exposed to the air for a long time, lost their power of 

 killing chickens. The inoculated birds were only locally affected, and 

 afterwards were immune to infection with virulent cultures. 



BACILLUS PHASIANI SEPTICUS. 



This organism was discovered by E. Klein in an epizootic amongst 

 young pheasants. The author isolated a morphologically identical 

 organism in an outbreak amongst some young pheasants, the mortality 

 being very great. The principal lesions were catarrhal inflammation 

 of the bowels and enlargement of the liver, with slight broncho- 

 pneumonia. 



Microscopical Appearances. Small bacilli, very like the Bacillus 

 coli communis, but smaller and shorter (see Photomicrograph, Fig. 67). 

 Motility . Strongly motile. 

 Spore Formation absent. 



Staining Reactions. Easily stained with any of the ordinary 

 aniline dyes, but not by the Gram method. 



Biological Characters. Similar to those of Bacillus coli communis, 

 except that milk is not coagulated. 



Pathogenesis. In the natural course of the disease, death takes 

 place among young pheasants in a few days or within a week. Young 

 pheasants are killed in twenty-four hours with a few drops of a bouillon 



