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VETERINARY BACTERIOLOGY 



THE GENUS SARCOCYSTIS 



These sporozoa are usually elongated, tubular, oval, or even 

 spherical. Cysts with a double membrane are formed, and in these 

 are produced reniform or sickle-shaped sporozo'ites, with a polar 

 capsule and a projectile thread. 



Species of this genus have been described from the muscles 

 of a large number of vertebrates. In most cases the organism 

 does not do any appreciable harm. Recently (1908) Watson has 

 called attention to the prevalence of sarcosporidiosis in western 



Fig. 208. Sarcocystis muris in the muscle of a mouse: 1, Mature organism 

 in the muscle; 2, isolated spores; 3, 4, 5, stages in the development of spores 

 (adapted from Negri). 



Canada, particularly in animals suspected of loco poisoning or 

 infected with dourine. Six cases were found in cattle and two in 

 horses suspected of being locoed, three in dourine-affected equines, 

 and one in a filly showing cachexia. He concludes that these or- 

 ganisms may sometimes be an important factor in disease. In 

 some cases the entire musculature may be affected with serious 

 and even fatal consequences. A close relationship between loco 

 poisoning and sarcosporidiosis is shown by the autopsy records. 

 Recovery from this affection and from dourine may be prevented 

 or retarded by the presence of the organisms. The species found 



