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PUBLIC HEALTH BACTERIOLOGY 



single or in short chains, and are shorter and thicker in 

 cultures. Chain formation seems to occur in the blood 

 chiefly, and never in artificial culture. Welch regards this 

 as an important distinction from anthrax bacilli. When 

 recovered from the body fluids it possesses a capsule. Each 

 bacillus forms one spore, which may be central or excentric. 

 Anaerobic ; non-motile ; non-flagellar ; Gram-positive ; 

 gelatin-liquefying (in most), and forming acid and gas in 

 glucose, lactose, and saccharose, but not in mannite. In 

 milk the reaction is similar to that described under B. 

 enteritidis sporogenes. It is highly pathogenic to guinea- 

 pigs but not to rabbits. 



Isolation. Make a suspension of the suspected material 

 (faeces, etc.) in sterile salt solution (i c.c. in 5 c.c). 

 Thoroughly emulsify and filter through a sterile paper, 

 and inject 1 to 2 c.c. of the filtered suspension into the ear 

 vein of a rabbit. After 5 minutes, kill the rabbit and 

 place its dead body in the incubator (37 C.) for 5 or 6 hours. 

 At the end of this time the animal is usually found tensely 

 distended with gas, and post mortem gas bubbles will be 

 found throughout the body, most characteristically in the 

 liver, where isolated bubbles are found on the surface. 

 From the bubbles, smears and cultures may be taken. 

 Identification is made from its morphology, capsule, non- 

 motility, and gas formation. In man, infection usually 

 follows traumatism. Distinction from B. enteritidis 

 sporogenes : non-motility, non-flagellar, not fermenting 

 mannite. Muir and Ritchie state that it is non-gelatin- 

 liquefying and non-pathogenic to guinea-pigs, but American 

 authors . describe it as above. 



Summary. 



