Seroprevalence of ovine brucellosis in south Wollo, north eastern Ethiopia

A cross-sectional study was conducted in south Wollo zone, north east Ethiopia between October, 2008 and March, 2009 aimed at determining the sero-prevalence and to identify potential risk factors of ovine brucellosis. A total of 800 sheep were sampled from two districts, Kalu and Harbu. All sheep above six months of age with no history of previous vaccination against brucellosis were selected. Rose Bengal Plate Test (RBPT) was utilized as a screening test for Brucella agglutinins while Complement Fixation Test (CFT) (Addlestone, United Kingdom) was used to confirm the reactors by RBPT. Over all seroprevalence of 1.5% (12 of 800) ovine brucellosis was observed. Seroprevalence was higher in female sheep compared to male sheep. Seroprevalence was calculated between sexually immature and sexually mature sheep, between animals kept under extensive and semi-intensive management system, and between animals of the two districts. Higher levels of sero-prevalence was observed in sexually mature sheep, in animals kept under extensive management system, and in sheep of Kalu with level of 1.54%, 1.6% and 1.58%, respectively. However, there was no statistically significant difference between the sero-prevalences of brucellosis in the different study groups of sheep. In conclusion, even though the prevalence of brucellosis observed in this study is low, it can be potential hazard for public health in the study area; therefore, the public especially small ruminant producers should be informed about the risk of ovine brucellosis.