172 Manual of Veterinary Microbiology. 



deposit is rarely absent. Miliary extravasations may 

 also be found in the nerve centers. 



Fig. 4. Microbe. —The blood, the dejections 



and the pericardial exudate contain, 

 „ , * ^ in large numbers, a micro-organism, 

 - J * very short and ovoid, resembling in 

 shape the figure 8. It is a diplo-bac- 

 i, ^ terium, the extremities of which are 



" less refringent and have more affinity 



1. Microbes of for the coloring matters than the mid- 

 chicken cholera die part, which remains clear. It 

 in figure 8 form; q^^q^ appears as a micrococcus ; this 

 2. The same in , , ^ . , , . i . , 



their real form— -"^ When its long axis corresponds with 



bacilli with clear the direction of the visual ray and the 

 central space. (M. organism is seen on one of its ends, 

 and L.) j^ -g jjiotile, its movements being very 



rapid in preparations of fresh blood.* It measures 

 from 0-6/i to 0-8// in length by 0-3/^ to 0-4/^ in thick- 

 ness. It is a facultative aerobe, oxygen, however, be- 

 ing favorable to its multiplication. 



Action of physical and chemical agents. — The bac- 

 teria of chicken cholera are killed in fifteen minutes 

 at 50°, in ten minutes at 80°, still more quickly at boil- 

 ing temperature. By desiccation they are killed in 

 a few daj^s. Corrosive sublimate, at 1 to 5,000, kills 

 them in one minute, carbolic acid, at three per cent, in 

 six hours. They are not affected by the gastric juice. 

 By the oxygen of the air they are first attenuated 

 and then killed. 



Cultures. — This germ grows well in bouillon in the 

 presence of air ; during its growth this medium 



* [Described in German works as non-motile.^D.J 



