Ethiopia is one of African country with nine regions and two city administration of which five regions were infected with more than one species of tsetse flies. Known species in Ethiopia are five in number namely Glossina pallidipes, G .morsitans, G. fuscipes, G. tachinoides and G. longipennis. Most tsetse transmission is cyclic and begins when blood from a trypanosome-infected animal is ingested by the fly. The clinical feature of the disease follows the level or burdens of tsetse challenge species. The main feature is anemia results in a progressive drop in packed cell volume, a non-specific but useful indicator in endemic areas. The most sensitive rapid method is examining a wet mount of the buffy coat area of a PCV tube after centrifugation, looking for motile parasites. The prevalence of trypanosomosis in enzootic area can be reduced by parasite control, vector control, host resistance protection prophylactic treatment and good husbandry management system. The methods of tsetse fly control involved bush clearing, elimination of game animals on which tsetse feed, and the sterile male technique (sterile insect techniques). Since female tsetse only mates once in a lifetime, this technique is theoretically able to eradicate a targeted tsetse species. Trypanotolerant animals are very important in tsetse fly challenging areas, but most countries did not accept them due to their low production of milk than indigenous breed. In conclusion, prevalence of trypanosomosis is devastating diseases of cattle in Ethiopia with both direct and indirect economic losses.
Key words: Bovine, trypanosomosis, nagana, tsetse fly, protozoa.