MAL DE CADERAS. 



Synomynis. Quebra Bunda, Broken Buttock ; Disease of the 

 Rump ; Infectious Paraplegia ; Paraplegic Trypanosomiasis. 



Definition. An acute trypanosomiasis of solipeds characterized 

 by fever, rapid emaciation, extreme anaemia, debility, dropsies, 

 advancing paraplegia, and almost always a fatal result. 



Historic Notes. Geographical distribution. I^ong familiar in 

 equatorial America, it was recognized in 1830 in the island of 

 Maraja as a sequel of the ruthless destruction of 60,000 horses 

 and the exposure of the carcasses without burial (Calendrini). 

 As a result the horses of the island were virtually exterminated. 

 At first the affection proved fatal in a few hours, but after a 

 year's prevalence, when the more susceptible animals had been 

 killed off, death was usually deferred as far as the 8th or 15th 

 day, and now it is from two or five months. A septic complica- 

 tion doubtless existed at first. At the present time the malady 

 prevails from Corrientes in the Argentine Republic on the south, 

 to Bolivia on the north, following especially the damp river 

 bottoms and other wet grounds. The whole basin of the Amazon 

 suffers, and especially Paru, Maranhb, Ccarii, Goya, Matto- 

 Grosso, and above all Maraja. In Argentina, Paraguay, Uru- 

 guay and Bolivia the marshy regions are severely ravaged. 



Animals Susceptible. Of farm animals the horse and dog, 

 suffer most severely, the ass and mule much less, while cattle, 

 sheep, goats and swine seem to resist casual infection, and give 

 but a mild reaction when inoculated. The cat is less susceptible 

 than the dog. The wild animals suffer about as follows : White 

 and gray mice and rats, Cabiai (^Hydrochaerus capybard), m,onkey, 

 coati, rabbit, and Guineapig. It exterminated the cabiai in 

 Marajo in 1830. Birds appear to be immune, though Voges 

 claims the infection of chickens, turkeys and ducks. 



Microbiology. The essential cause is the Trypanosoma Equi- 

 num discovered by Elmassian in igoi and confirmed by Voges. 

 It is 24 to 26 }). long, by I to 2 /x broad, with a fiagellum as 

 long as the body, extending back from the head, in the undulat- 

 ing membrane, for two-thirds of the body length. A distinctive 

 feature of this trypanosoma is the lighter coloration of the 

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