56 STUDY AND IDENTIFICATION OF BACTERIA 



For cultural characteristics see key. Spores develop best at incubator 

 temperature. 



Stiles thinks that animals are infected by eating the bones of 

 animals which have died of anthrax, cutting buccal mucous membrane, 

 and so becoming infected. Spores do not form in an intact animal 

 body, but they do form after a postmortem or the disintegration of 

 the body by maggots. For this reason it is better not to open up the 

 body of the animal, but to make the diagnosis by cutting off an ear. 



FIG. 18. Bacillus anthracis in blood of rabbit. (Coplin.} 

 Dried spores will live for years and will withstand boiling temperature 

 for hours. 



In vaccinating animals against anthrax, Pasteur used two vaccines. 

 The first is attenuated fifteen days at 42.5 C., The second, attenuated 

 for only ten days, is given twelve days later. 



In taking material from a malignant pustule before excision, be 

 careful not to manipulate it roughly, as bacteria may enter the circula- 

 tion. Make cover-glass preparations, staining by Gram. Make 

 culture on agar. Blood cultures are usually only positive later in the 

 disease. Inoculate a guinea-pig or a mouse subcutaneously. 



SPORE-BEARING ANAEROBES. 



There are three very important pathogens in this group that of 

 malignant oedema; that of botulism, and the organism of tetanus. 

 The B. enteritidis sporogenes is of importance in connection with 



