ORGANS OF LOCOMOTION 147 



legs. Although no opportunity for the examination of 

 the muscle from these cases has arisen, the writer has 

 thought the condition is probably due to sarcosporidiosis. 



Etiology. The Sarcocystis miescheri is the cause of 

 sarccsporidiosis. The exact life cycle of this parasite is 

 unknown. 



Lesions. The cysts are usually so small that they 

 cannot be detected without the use of a microscope. 

 However, an unusual specimen was obtained by York 

 at an abattoir in Chicago in which the cysts could be 

 readily detected as grayish- white ovoid patches. Micro- 

 scopically, the parasites are found within the muscle 

 sarcolemma. They appear to destroy or displace the 

 muscle substance, the fiber being entirely severed, the 

 sarcolemma alone remaining intact. The sarcocysts 

 contain many round or oval bodies/ the sporozoi'tes. 

 The cysts undergo degeneration and calcify, but at 

 what age these changes occur has not been determined. 



Symptoms. The disease has not been recognized 

 clinically, but no doubt infestation would interfere with 

 the muscle function. 



Treatment. Therapeutic treatment is not available, 

 and in the absence of a definite knowledge of the life 

 cycle of the parasite, preventive measures are only 

 problematic. General sanitation should be maintained. 



Tumors 



An occasional tumor is encountered that has invaded 

 the muscular or osseous tissue of swine. But, generally 

 speaking, tumors of these structures are of little signifi- 

 cance. 



