458 INFECTIOUS DISEASES DUE TO PROTOZOA 



and dies of inanition. The appetite is well retained through- 

 out the disease. In some cases keratitis, corneal abscess, 

 iritis and blindness develop during the attack. Urticaria 

 - (plaques) may also be noted occasionally. 



Diagnosis. — Depends upon a knowledge of the prevalency 

 of the disease in the district, the symptoms of remittent 

 fever, edemas, emaciation and weakness (in spite of good 

 appetite), and the demonstration of the trypanosomes in 

 the lymph glands, blood and edematous swellings. When the 

 microscopic findings are negative, dogs should be inoculated. 



Prevention. — Same as in Surra. 



Mai de Caderas. 1 — Definition. — Mai de Caderas is a 

 South American disease of horses due to the Trypanosoma 

 equinum. It is characterized by fever, paralysis of the 

 hind parts, urticaria, edemas of pendent portions of the body, 

 keratitis, anemia and emaciation. 



Occurrence. — The disease is found in Brazil, Batavia, 

 Argentine, Paraguay, and on the islands of the delta of the 

 Amazon. Like most trypanosomiasis, Mai de Caderas is 

 found in swampy localities. In infected districts in Argentine 

 the disease plays havoc with the horse industry. 



Etiology. — The cause of Mai de Caderas is the Trypano- 

 soma equinum (T. elmassiana), which is very similar to the 

 Trypanosoma brucei of nagana. 



The mode of transmission of the disease from animal to 

 animal is as yet unsolved. Formerly horse flies (Stomoxys 

 brava), tabanidea and even mosquitoes were accused. 



Doubt has been cast upon this assumption by the fact 

 that a wire fence is sufficient to prevent the spread of the 

 disease. It is probable that the disease is transmitted 

 indirectly by the capybara (a large rodent). The capybaras 

 are .said to die in great numbers and are eaten by dogs, from 

 which a spread to horses is assumed. 



Symptoms. — The period of incubation is about ten days. 

 The most prominent symptom is weakness of the hind parts, 

 loss of coordination, the hindlegs being dragged and the 

 fetlocks knuckling over when walking. The patient rapidly 



1 Mai de Caderas, "hip disease," from a prominent symptom. 



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