A study to characterize the brucellosis epidemiological situation in the State of Rondônia was carried out. The State was divided into three regions. Three hundred herds were randomly sampled in each region. A pre-established number of animals were sampled in each of these herds. From 927 herds and 9,717 serum samples were collected. In each herd, it was applied an epidemiological questionnaire regarding herd features and also husbandry and sanitary practices that could be associated with risk of infection. The serum samples were screened for antibodies to Brucella spp. by the Rose-Bengal Test (RBT), and all RBT-positive sera were re-tested by the 2-mercaptoethanol test (2-ME). The herd was considered positive if at least one animal was positive on both RBT and 2-ME tests. The prevalences of infected herds and animals in Rondônia State were 35.2% [32.1-38.4%] and 6.2% [4.9-7.6%], respectively. In the regions, the prevalences of infected herds and animals were, respectively: region 1, 41.9% [36.3-47.6%] and 8.3% [5.9-10.8%]; region 2, 31.7% [26.5-37.2%] and 5.9% [4.3-7.6%]; and region 3, 31.9% [26.7-37.4%] and 4.6% [2.5-6.6%]. The risk factors (odds ratio, OR) associated with the presence of the infection were: recent history of abortion (OR= 1.42 [1.04-1.95]) and beef herd (OR=1.75 [1.30-2.38]).
cattle; brucellosis; prevalence; risk factors; Rondônia; Brazil