A cross-sectional study was conducted from November 2020 to March 2020 to estimate the seroprevalence of bovine trypanosomosis, identify associated risk factors and assess the density of Glossina species and other biting flies in the Tambaro district of Southwest Ethiopia. A total of 384 cattle were selected by systematic random sampling technique. Cotton dumped in 70% alcohol and disinfected the site on-ear and piercing vein by lancet then sucking the blood with hematocrit tube; after collecting the blood it was centrifuged. Packed cell volume (PCV<26) was determined as trypanosomosis positive. After the PCV was read capillary tube was broken 1mm blow the buffy coat put on a microscopic slide observed for any movement on a slide which is used to identify the trypanosome species. The overall prevalence of bovine trypanosomosis in the study area was 17%. Out of positive cases Trypanosome conglense (81.6%) was the dominant trypanosome species followed by T.vivax (15.7%) and mixed T. conglense and a T.vivax (2%). The prevalence of trypanosomosis on the basis of risk factors was; exotic breed (OR: 5, P=0.000), black hair coat (OR: 3.7, p=0.01), body condition; poor (OR: 4.2, p = 0.01). 37 odor baited acetone and cow urine were used to attract flies in the forest and put under the deployed NGU traps. A total 37NGU traps were deployed for 72 hours and 261 Glassina (G. pallidepes and G. fuscipes) were collected from the study area of which higher density of tsetse flies 192 (8 flies per trap per day) followed by 50 Stomoxys and 19 Tabanus. Generally, this study showed that trypanosomosis in the Tambaro district is still a core problem for livestock health, production, and productivity. Therefore, more attention should be given both by the government and the community to decrease the negative impact of trypanosomosis and its vectors through an integrated approach to control both the disease and its vectors.

Keywords: Buffy coat, Prevalence, Tambaro, Trypanosomosis, Tsetse fly