Epidemiology of bovine trypanosomiasis in the Ghibe valley, southwest Ethiopia 1. Tsetse challenge and its relationship to trypanosome prevalence in cattle

In this, the first of a series of papers on the epidemiology of bovine trypanosomiasis in the Ghibe valley, southwest Ethiopia, the tsetse populations and their relationships to the prevalence of trypanosome infections in cattle are described. The tsetse challenge to cattle at two sites in the area was estimated as the product of tsetse relative density and the trypanosome infection rate in flies. The proportion of feeds taken by tsetse from cattle was also considered. Three tsetse species were detected in the area, Glossina pallidipes, G. fuscipes and G. morsitans submorsitans. A significant correlation ( r=0.60, P