170 Manual of Veterinary Microbiology. 



which the two extremities, possessing more affinity 

 for the coloring matter, are separated by a clear 

 apace. This microbe, once colored, is decolorized by 

 the methods of Gram and of Weigert. It is found in 

 large numbers in the blood and in most of the organs 

 when the disease has lasted for some time; on the 

 contrary, it is much rarer in very acute forms. 



Its culture is easy; it behaves as a facultative 

 anaerobe and reproduces itself in the form of a mo- 

 tile diplococcus recalling absolutely the microbe of 

 chicken cholera. After twenty days exposure to the 

 air, its cultures in bouillon have lost all virulence. 

 When growing in bouillon the latter becomes turbid, 

 then clear again ; gelatin is not fluidified and the cul- 

 ture in this medium takes the form of a thick, white, 

 glistening track, dentated at its margin. 



The disease is readily transmitted from rabbit to 

 rabbit ; it is also inoculable to the guinea pig and to 

 all species of birds, in which it occasions symptoms 

 resembling those of avian cholera. When the virus 

 is inoculated in the pectoral muscle it produces a se- 

 questrum in all respects comparable to that caused 

 by the inoculation of this last disease. 



Chicken cholera. {Fowl cholera.) 

 This is an extremely fatal disease which prevails 

 epizootically among farm-yard fowls. It is charac- 

 terized by easily recognizable symptoms : the affected 

 animals lose their accustomed vigor, generally as- 

 sume the sitting posture, or move listlessly around; 

 they are chilly and seek the sunshine, their plumage 

 is ruffled, giving them the appearance of a ball of 

 feathers; the comb becomes purple, bluish, or even 



