Anti-Brucella spp. antibodies in working equids in a semiarid region of Northeastern Brazil

The present study described the prevalence and factors associated with the seropositivity for anti-Brucella spp. antibodies in working equids in the semiarid regionofnortheastern Brazil. Blood samples were collected from 322 equids (76 horses, 155 mules and 91 donkeys). The Rose Bengal plate test (RBPT) was used as a screening method. Samples that were reactive in the RBPT were tested for confirmation using 2-mercaptoethanol (2-ME) and the standard tube agglutination test (STAT). Overall, 7.1% (23/322) of the samples were positive according to the RBPT. After confirmatory tests, the prevalence of brucellosis was found to be 6.5% (21/322). Among these cases, 33.3% (7/21) were horses, 42.8% (9/21) were mules and 23.9% (5/21) were donkeys. In the multivariate analysis, age over 10 years was considered to be a factor associated with the seropositivity (OR: 17.17; 95% CI: 2.582-164.7, P = 0.006) for anti-Brucella spp. antibodies. The significant prevalence of anti-Brucella spp. antibodies found in working equids and the wide distribution of positive animals demonstrates a worrying epidemiological situation regarding brucellosis in the study region. Age over 10 years was a risk factor associated with the seropositivity for anti-Brucella spp. antibodies in animals.