Ayana, Dinka (PhD)Yilma, Melese2018-06-292023-11-082018-06-292023-11-082016-06http://etd.aau.edu.et/handle/123456789/4874Brucellosis is an important infectious disease causes significant reproductive losses in sexually mature animals and zoonotic hazard. A cross sectional seroprevalence survey was conducted from November 2015 to March 2016 in Arba Minch Zuria and Mirab Abaya districts of Gamo Gofa zone with the objective of isolation and biochemical characterization of Brucella agent from seropositive clinical cases in small ruminants of the area. The districts were selected purposively following community based breed improvement program in the vicinity by the ILRI, 120 representative households from the breeding cooperative were randomly selected to generate information on flock reproductive health disorder. A total of 1000 serum samples (Goat, n=889 goats and sheep, n=111) were collected and screened using mRBPT, from screened test positive animals (11.3%) isolation rate were recorded. The five isolates were from vaginal swab, one isolate from placental cotyledon and suspected for two Brucella spp. through biochemical characteristic nature. On the basis of serological tests, the individual animal level seroprevalence of brucellosis was 4.3% (95%CI: 30.41, 55.59), 3.8% (95%CI: 26.13, 49.87) and 3.7% (95% CI: 25.3, 48.72) using m-RBPT, ELISA and CFT respectively. Flock level seroprevalence across the two districts was 10.81% (95% CI: 0.96, 7.90), 37.84% (95%CI: 6.81, 21.2) and 51.4% (95% CI10.64, 27.4) for small, medium and large flock size respectively. The kappa statistics almost perfect agreement (0.922 and 0.958) was record among the test mRBPT and ELISA respectively with reference to CFT. The identified putative risk factors for small ruminants Brucellosis in this study were fit using multivariable logistic regression. Odds of the risk factors at 95% confidence interval district (OR=10.35, 95%CI: 3.99, 26.8), flock size (OR=3.45, 97%CI: 1.12, 10.27), parity (OR=6.3195%CI: 1.82, 21.8), age (OR=3.43, 95%CI: 1.12, 10.51), history of reproductive health problems (OR=6.21, 95%CI: 3.16, 12.21) and source of breeding animals (OR=2.6, 95%CI: 1.33-5.06) were recorded. Also in the survey results show there was poor management of reproductive health problem and which could contribute to spread of brucellosis infection in the production system since breeding was not controlled. Therefore, particular in breeding programs strategic control measures should be implemented, such as regular testing of breeding animals, to reduce brucellosis economic impact and risk of zoonosis in the community. Key word: Brucella, Gamo Gofa, Isolate, seroprevalence, Small ruminantsenBrucellaGamo GofaIsolateseroprevalenceSmall ruminantsThesis