268 VETERINARY BACTERIOLOGY 



Isolation and Culture. Isolation is accomplished by plating 

 upon gelatin. Growth upon most media resembles that of the 

 B. lactis aerogenes. Milk is not coagulated, although litmus milk 

 is reddened. 



Physiology. The organism shows markedly less fermentative 

 power than B. lactis aerogenes, but otherwise closely resembles it. 

 Dextrose, lactose, and saccharose are all fermented, but usually 

 not vigorously. Growth occurs at blood-heat, but the organism 

 develops well at room-temperature. The thermal death-point is 

 about 56. Indol is produced. 



Pathogenesis. B. pneumonias has a very low virulence only 

 exceptionally will it infect any of the lower animals. It has been 

 isolated in pure culture from the vegetations upon the heart 

 valve in endocarditis, from otitis media, and occasionally it is 

 believed to cause catarrhal or lobular pneumonia. It is noted 

 here simply because of the possibility of isolation in various infec- 

 tions, and because of its obvious relationship to the preceding 

 organisms of the group. 



SUBGROUP n INTERMEDIATE, HOG-CHOLERA, OR ENTERITIDIS 



SUBGROUP 



The classification and relationships of the organisms belonging 

 to this subgroup are much confused at present. Whether or not 

 the various forms described are all distinct species is doubtful. 

 The most important will be discussed under the names by which 

 they are commonly known, but this uncertainty as to correct 

 grouping must constantly be borne in mind. 



Bacillus cnteritidis 



Synonym. Bacillus of Gartner. 



Diseases Produced. Meat-poisoning and enteritis in man and 

 in cattle. 



Gartner, in 1888, studied an outbreak of meat-poisoning in a 

 village in Saxony, and isolated from a fatal case and from the 

 uncooked flesh of a cow the organism now known as Bacillus 

 enteritidis. This organism has since that time been found in 

 similar outbreaks of meat-poisoning and associated with certain 



