360 VETERINARY BACTERIOLOGY 



usually equatorial, but sometimes polar. The rod is not greatly 

 distended by the spore, although the snowshoe or clostridium 

 shape is usually evident. The organism is gram-negative, and 

 stains readily with the common anilin dyes. 



Isolation and Culture. The organism may be secured in pure 

 cultures without difficulty, under anaerobic conditions, from the 

 edematous tissues of the infected animal. It may usually be 

 isolated from garden-soil by inoculation of a guinea-pig or a rabbit. 

 Its cultural characters do not differ from those described for 

 Bacillus chauvcei. Gelatin and blood-serum are digested, milk is 

 curdled, and the casein digested. 



Fig. 151. Bacillus cedematis, tissue smear showing rods without spores 

 (Frankel and Pfeiffer). 



Physiology. Growth is luxuriant at room-temperatures, as well 

 as at blood-heat. The spores are resistant to desiccation and to 

 heat. Gas is produced from dextrose, probably also from pro- 

 teins. Enzymes that liquefy gelatin, blood-serum, and casein 

 are present. 



Pathogenesis. Experimental Evidence. Inoculation of pure 

 cultures of the organism into the laboratory animals, and also into 

 the horse and other domestic animals, will produce a typical infec- 

 tion. 



Character of Disease and Lesions Produced. The tissues 

 at the point of invasion are distended with gas-bubbles and are 

 infiltrated with yellow or red serum. The muscle becomes dark 



