A parasitological survey for bovine trypanosomosis in the livestock-wildlife ecozone of Northern Tanzania

Aim: Tsetse-transmitted animal and human trypanosomosis is considered to be one of the major constraints to improved livestock and agricultural production in sub-Saharan Africa. A cross sectional survey to determine the prevalence of trypanosomosis and identifying trypanosome species infecting cattle was conducted in Makuyuni division, Arusha region of northern Tanzania, an area where livestock and wildlife graze together. Materials and methods: A total of 239 indigenous Tanzania short horn zebu cattle at four different villages, and of different ages and sex, were randomly selected and sampled. Field examination of Giemsa stained thick and thin blood smears was undertaken. Results: The overall prevalence of slides positive for bovine trypanosomosis was 5% (95% [confidence interval], CI = 2.68.6). The prevalence was significantly higher in Mswaki juu village (7%) and lower in Ortukai (3%). Of the positive cattle, 8/12 (66.6%) had infections with T. vivax and 4/12 (33.3%) T. congolense. No cases of T. brucei were detected. Animals with poor (13.7%) body score were significantly associated with high prevalence of trypanosomes infection than animals with good (2.7%) score. Prevalence of trypanosomes infections was significantly higher in males (8.42%) than in females (2.47%) and increased markedly in cattle aged >4.5 years, with no significant difference among the age group. Conclusion: Because of the risk of trypanosomosis in the Mswaki juu, a locality which is close to a wildlife Reserve; integrated tsetse and trypanosomosis control strategies need to be improved and enforced.