PATHOGENIC PROTOZOA OF THE MASTIGOPHORA 433 



experimentally produced by the inoculation of the organism into 

 sheep, cattle, goats, rabbits, horses, and white rats. 



Character of Disease and Lesions. The infection is acute in the 

 rat; acute or chronic in the rabbit and dog; and chronic in the 

 ox, sheep, and in equines. It produces a severe anemia with 

 changes in the red blood-cells. In the horse there is progressive 

 emaciation. A marked edema is rarely produced. Death does 

 not occur usually for months after infection. Recovery sometimes 

 occurs. 



Immunity. No practicable method of immunization by means 

 of the organism or its products has been developed. 



Bacteriological Diagnosis. The organism may be found in the 

 blood at certain periods, but repeated examination is sometimes 

 necessary. Inoculation of other animals with the blood will 

 nevertheless show it still to be infective. 



Transmission. Pecaud states that immediate transmission 

 may be due to a fly, Stomoxys. Tsetse flies are found in the region 

 in which the disease is found, and may be responsible for its spread. 

 The exact method of transmission is not certainly known. 



Trypanosoma congolense 



Brodin described a disease in the Congo Free State which 

 closely simulated nagana, but the trypanosome resembled rather 

 Tr. dimorphon. Laveran, as a result of inoculation experiments, 

 has concluded that this is a distinct species. It has been reported 

 from several localities in southern Africa. It is fatal for cattle 

 and sheep. The organisms are 10.5 to 15.5 u in length and 1.7 to 

 2.5 u wide. The flagellum shows no free portion, hence animal 

 inoculations are necessary to differentiate between this and Tr. 

 dimorphon. 



Trypanosoma pccaodi 



Disease Produced. Baleri or trypanosomiasis in horses, 

 cattle, sheep, and goats. 



This organism was described by Laveran from the blood of 

 inoculated sheep brought to Paris by Cazalbou. 



Distribution. The disease is known from the French Sudan. 



Morphology. The organism closely resembles Tr. dimorphon. 



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