554 



Some Observations on Trypanosoma pecorum (Bruce) and 

 T. uniforme (Bruce). 

 By H. L. Duke. 



(Communicated by Sir J. R. Bradford, K.C.M.G., Sec. R.S. Received 

 August 16, 1912.) 



The fact that antelope play a considerable part in nature as a reservoir for 

 T. gambiense has now been thoroughly established. Both laboratory and field 

 results agree in confirming the suspicion which for some time past has 

 attached to these animals. In the case of T. gambiense, however, there is 

 nothing very remarkable in the observation that the presence of the 

 trypanosome in their blood apparently exerts no harmful effect on the 

 antelope. T. gambiense cannot be considered as a fatal trypanosome for 

 ruminants generally. In the case of T. pecorum, however, matters are 

 different. This trypanosome, according to Bruce and his collaborators, causes 

 a rapidly fatal disease in cattle and domestic animals generally. Though 

 apparently widely distributed throughout Uganda, nothing definite is at 

 present known concerning its true carrier in nature. The presence of the 

 •disease in districts where tsetse are unknown shows that some other agent 

 is capable of conveying this trypanosome. The behaviour of laboratory- 

 bred Glossina palpalis as carriers is so uncertain that this fly would appear 

 ■at most to be a facultative host, though doubtless under favourable 

 circumstances it may play an important part in nature. Again, nothing 

 is known concerning the existence of a natural reservoir for this trypanosome 

 in Uganda, though Kleine has recently obtained species closely allied to, if 

 not identical with, T. nanum and T. congolense from antelope in the neighbour- 

 hood of Tanganyika. The following experiments were undertaken with a 

 view to discovering whether T. pecorum is pathogenic to antelope, and at the 

 same time to test the power of these animals to act as a reservoir for the 

 trypanosome : — 



A young bushbuck, born at the laboratory in January, 1911, was inoculated 

 with blood of a monkey suffering from T. pecorum. After an incubation 

 period of 15 days trypanosomes appeared in the blood of the bushbuck on 

 May 31, 1911, being present for some days and then disappearing. Clean 

 laboratory-bred G. palpalis were then fed upon the bushbuck and afterwards 

 on clean monkeys. These experiments are given in Table I. As will be seen, 

 in only one instance was a positive transmission obtained, and this was 

 unfortunately not entirely satisfactory, as will be explained below. 



