Detection of Brucella abortus B19 strain DNA in seminal plasma by polymerase chain reaction in Brazil.

A total of 27 seminal plasma samples from cattle-breeding farms or semen centres located in Minas Gerais, Brazil, previously negative by serological and tested positive for Brucella spp. with primer specific for the amplification of the gene virb5 by polymerase chain reaction (PCR) were analysed for the detection of Brucella abortus DNA by PCR. It was found that nine samples (33.33%) contained B. abortus B19 strain DNA, two (7.40%) contained B. abortus DNA and five (18.51%) contained both DNA. The larger number of samples with B. abortus B19 strain DNA would explained by the environmental contamination by vaccinated females with persistent excretion or some illegal vaccination process. It is first reported of male bovines detected with both DNA.