The Role of Sheep in the Epidemiology of Camel Trypanosomosis in Kordofan States

This study was designed to estimate the natural infection rate with Trypanosoma evansi in mixed herds of sheep and camels. 225 blood and serum samples of camels and 75 of sheep were collected from the selected sites of the study area in Kordofan States during the three main seasons of the yearly, namely hot dry, hot wet and cool dry seasons. The parasitological examinations used to detect the parasite based on wet, fixed stained blood films and the microhematocrit technique (MHCT) revealed 11% of the collected camel blood to be positive, where as the same methods failed to detect any parasite in blood samples of sheep. When the Card Agglutination Test for T. evansi (CATT) was used 44% of camels and 20% of sheep were found to have circulating antibodies against T. evansi. These results support the fact that the parasitological methods are insufficient in trypanosomosis diagnosis. So further sensitive tests for antibodies or antigens detection were needed to have accurate specific results. Experimental infection of sheep with T. evansi isolated from camel performed to study the susceptibility and pathogenicity of T. evansi to sheep. Clinical signs, parasitological and hematological changes that resulted from the infection were studied. Daily parasiteamia, body temprature records and weekly body weight, blood and serum collections for five weeks to study the changes in the blood parameters, serum for serological diagnosis of T. evansi by using (CATT) and some electrolytes and proteins estimation that indicate some affections of vital organs. Treatment of the experimentally infected sheep with Quinpyramine sulphate (Antrycide) at a dose rate of 3 mg/kg body weight resulted in complete disappe arance of the parasite from the peripheral blood but antitrypanosomal antibodies remained circulating for 5 weeks post treatment at a serum dilution of 1: 16. Sheep were found to be susceptible to T. evansi with varying incubation periods. The incubation period was significantly reduced when sheep infected blood was passaged to sheep. The inoculum seemed to be effective in the production of the disease as well as the route of inoculation. The sheep used in this experiment showed mild clinical signs which means that they can act as potential reservoirs.This is supported by the low parasiteamia which could be missed in routine examinations