Diagnosis of bovine brucellosis in bulls by seroagglutination and seminal plasma agglutination tests

Brucellosis is a zoonotic disease with common agent is Brucella abortus in bovine specie. The disease in bulls is usually asymptomatic and could have absence of anti-B. abortus antibody in serum. It was investigated of the occurrence of bovine brucellosis in bulls, which involved testing blood serum and seminal plasma from 177 bulls used for natural mating or as semen donors. Blood was collected from all the animals by venipuncture of the jugular vein to obtain the serum samples, while seminal plasma was obtained from the animals by electroejaculation. Samples were tested in a screening test (rose bengal test). In the second stage, the samples testing positive in the RBT were subjected to the confirmatory test (2-mercaptoethanol). None of the animals tested positive when blood serum was used. However, 5.06% of the bulls were considered reagent positive when seminal plasma was tested. It also sought to determine whether there was an association between the kind of production and the destination of animals with positive results. The calculated odds ratio indicated that bulls of the kind of production dairy/both (beef and dairy) had a higher risk of brucellosis infection. It is recommended that seminal plasma agglutination and seroagglutination techniques are applied concomitantly.