Prevalence of donkey trypanosomosis in selected districts of west Wollega Zone, Western Oromiya

A cross-sectional study was conducted in October 2015 to December 2016 in eleven (11) peasant associations (PAs) randomly selected from three purposively chosen districts (Gimbi, Lalo Assabi and Nedjo) of West Wollega Zone, Oromiya Regional State, Western Ethiopia to estimate the prevalence of donkey trypanosomosis and to identify the trypanosomes species involved and their relationship with the mean PCV. Blood samples were collected from the ear vein of randomly selected 384 donkeys and examined by Buffy coat technique. The overall prevalence of trypanosome infection in donkeys was 18.8% (n=72) and different prevalence rates of donkey trypanosomosis were recorded in Gimbi (11.3%), Lalo Assabi (8.4%) and Nedjo (32.7%) in which highest prevalence was observed. However, the disease was statistically significant among animals from Gimbi (P=0.000, OR=3.807, CI=1.947-7.44) and Lalo Assabi (P=0.000, OR=5.3, CI=2.5-11) districts as compared to those animals sampled from Nedjo district. Highest (43.1%) and lowest (8%) prevalence of the disease was recorded in Waligalte Adda PA of Nedjo district and Gimbi 01, respectively. However, prevalence of donkey trypanosomosis was statistically significant (p<0.05) in only two PAs (Werego Arsema and Enango 01) of Lalo Assabi district. Higher prevalence rate was observed in adult (21.1%) than young (11.6%) age groups and in male (27.4%) than in female donkeys (12.3%). Also highest prevalence was seen in animals with poor body condition. Age, sex and body condition showed a significant association with the prevalence of donkey trypanosomosis in the areas (p<0.05). Trypanosoma vivax (37.5%) was the most predominant trypanosome species encountered during the study period followed by T. congolense (26.4%), T. brucei (26.1%) and mixed parasites (13.9%). High distribution of different species of Trypanosoma parasites was detected in Nedjo district. The overall mean PCV values were 21.2% and 43.2% for infected and non-infected animals, respectively. Statistically significant difference (P<0.05) was observed between the overall mean PCV values of infected and non-infected animals and the mean PCV was found to be dependent on PAs, Sexes, Ages and body conditions of donkeys. In conclusion, the result obtained in this study is an important disease of donkeys in the study areas where donkeys are extensively kept and used. So, further longitudinal study should be conducted in the areas to generate a complete data of the disease in the study areas.