4'JO VETERINARY BACTERIOLOGY 



Not all trypanosome infections are transmitted through insects. 

 Certain transformations have been noted with some forms in the 

 body itself. There is no evidence that an insect can transfer the 

 organism to its progeny; that is, hereditary transmission through 

 insects plays no part in the life-history. This is in marked con- 

 trast to certain other diseases, such as the piroplasmoses. 



Cultivation of Trypanosomes. Novy and MacNeal, in 1903, 

 gave an account of a method which they had successfully used in 

 the cultivation of trypanosomes in artificial media. Equal parts of 

 defibrinated rabbit blood and melted nutrient agar are mixed, and 

 the tubes are slanted and allowed to solidify. The water of con- 

 densation is inoculated with a small amount of blood containing 

 trypanosomes. The first culture of trypanosomes frequently 

 develops slowly, but subsequent transfers more quickly. Not all 

 trypanosomes can be cultivated in this manner with equal facility. 



Method of Disease Production. The organisms are found 

 typically in the circulating blood, and to a less degree in the other 

 body-fluids. Anemia and emaciation are frequently associated 

 with the various trypanosome infections. The spleen is quite 

 commonly enlarged. 



Examination and Staining Methods. Usually the examination 

 under a cover-glass of a drop of blood from an infected animal will 

 reveal the organism, particularly if made directly with the low- 

 power objective of the microscope. The active motion of the 

 organisms reveals their presence by movements of the blood-cells, 

 and they may be thus located and then studied under the higher 

 powers. Centrifugation of blood or body-fluids must be resorted 

 to in some instances to concentrate the cells when they are present 

 in small numbers only. Blood-films stained by Wright's method 

 yield very satisfactory results. 



Trypanosoma equiperdum 



Synonym. Tr. rougeti. 



Disease Produced. Dourine: maladie du coit in horses (horse 

 syphilis). 



Rouget, in 1896, first described this trypanosome. Other 

 investigators have conclusively established its etiologic relation- 

 ship to the disease. It is of particular int< r -t M the only try- 



