Brucella DNA is not detected in in-vitro produced embryos derived from ovaries of naturally infected buffaloes

Abstract

The aim of this study was to screen for Brucella spp. buffalo embryos produced in- vitro, by using cumulus oocytes complexes (COCs) recovered from ovaries of slaughtered buffaloes naturally infected with Brucella spp. Ovaries were collected from 5 female pluriparous buffaloes slaughtered in a local abattoir. EDTA-blood samples and nasal swabs collected from each animal were used for Brucella spp. DNA detection by real-time PCR. Buffalo ovaries (n = 10) were transported to the laboratory and maintained strictly separated throughout laboratory processing. Recovered COCs were matured, fertilized and cultured in vitro until day 7. Some immature COCs, all uncleaved COCs, all blocked cleaved embryos (2 to 16 cells) and all transferable embryos (tight morulae and blastocysts) were separately analysed by real-time PCR assay. Brucella spp. DNA was detected in both blood and nasal mucus of all subjects, whereas no trace of DNA of Brucella spp. was found on either COCs or embryos. Currently, the infected or seropositive buffaloes have to be slaughtered for sanitary reasons. Interestingly, the results of this preliminary trial suggest a possible utilization of the COCs from the infected subjects of high genetic value to obtain safe embryos.