SAROOSPORIDIOSIS. 



A contribution on, with especial reference to its associations with ' Loco ' disease 

 and Dourine, and the possibility of mistaking the spores of Sarcocystis for 

 certain so-called developmental forms of trypanosomata. 



Although Sarcosporidiae are of common occurrence in the musculature of domesti- 

 cated animals, very little is known concerning 'the life-history of the parasites, and . 

 nothing but supposition as to the means by which their hosts become infected. 

 Further, a marked uncertainty or contradiction exists as to the "power these parasites 

 possess in producing a serious and recognizable disease. 



It would appear that in the majority of cases of infection, in otherwise healthy 

 animals, the invasion is a very limited and harmless one, involving to a more or less 

 slight extent the muscles of the oesophagus and tongue, but that in certain conditions, 

 generally of obscure origin, and briefly designated under the term ' cachetic, the 

 parasites may overrun the entire muscular system and become a grave menace to the 

 life of their hosts. 



A brief resume of the more important observations on the subject by various 

 authors is here given : — 



NOMENCLATURE. 



(a) Muscular Psorospermosis. 



(b) The sarcoysts, tubes, sacs or utricles of Miescher. 



(c) Eainey's corpuscles (the spores of the cysts). 



(d) Sarcosporidiosis. 



It is stated in Neumann's Parasites, that about 40 per cent of pigs may be 

 infected. Moule, quoted by the same authority, found the parasites in 98 per cent of 

 cachetic sheep, usually numerous in proportion as the cachexia is more accentuated. 

 In 100 sheep in good condition he met with them in 44, and then always in small 

 numbers. Of 100 oxen condemned for being in extremely bad condition he found 

 37 infected with Sarcosporidiae. In cattle in good condition he found them only 

 in three instances. 



Schulze noted their presence in the muscles of the forehand of a horse, destroyed 

 on account of paralysis of the anterior limbs. Some similar examples are also 

 recorded by Neumann. The following extracts are quoted from Minchin's 2 account 

 of the Sarcosporidiae : — 



' In acute cases all the skeletal muscles may be infected, even those of the head 

 . . . . the parasite grows until it distendb the fibre to five or even ten times its 

 normal breadth absorbing the contractile substance as it does so. . . . The cysts 

 are observed to degenerate in some cases, their adventitious walls becoming calcified, 

 in other cases the cysts burst and spread their contents in the surrounding tissues, 

 destroying the muscles and producing tumors and abscesses. 



' The symptoms of Sarcosporidiosis in the pig are paralysis of the hinder extre- 

 mities, a skin eruption, and general symptoms of sickness, such as thirst, increased 

 body-temperature, and dim, streaming eyes. 



'The disease is sometimes the cause of fatal epizootics among domestic animals, 

 especially sheep. In the mouse also Sarcocystis muris is a very deadly parasite. . 

 Laveran and Mesnil have isolated the toxine of the Sarcosporidian parasite of the 

 sheep, and named it Sarcocystjne, a substance found to be extremely toxic for the 

 experimental rabbit.' 



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