NAGANA 



137 



about 85%. Hemoglobinuria has been observed in some cases. 



Musgrave and Clegg state that it may occur temporarily in the 



first stage of the disease. Leucocy- 



tosis is given as being constantly 



present. A detailed study of the 



changes in the blood has apparentl}' 



not been made. 



NAGANA 



Trypanosoma brucei is very similar 

 to Tr. evansi. Laveran and Mesnil 

 consider that there are certain differ- 

 ences, — that Tr. evansi is more slender, 

 has a longer flagellum and is more ac- 

 tively motile in hanging drop and that 

 animals immunized to one are not to 

 the other species. 



The parasites are present in the 

 blood in sufficient numbers to be 

 found on microscopical examination 

 during the febrile periods; but during 

 the intermissions may be very scarce. 

 Inoculation of susceptible animals 

 however, shows them to be present 

 even when the microscope fails to re- 

 veal their presence. Toward the end 

 of the disease they are often present 

 in both febrile and afebrile periods 

 in considerable numbers. There may 

 be 50,000-70,000 per cmm. on the day 

 of death (Theiler). 



Kanthack, Durham and Blandford 

 found the trypanosomes present in 

 the right inguinal lymph glands in animals inoculated subcutane- 

 ously in the right side one to three days before they were dis- 

 coverable in the blood. 



Fig. 17. Trypanosoma 

 brucei, rat's blood (Nocht and 

 Mayer) . 



