AimThe aim of this study was to determine whether the practice of co-grazing with cattle and wild life constitutes a risk of transmission of antibiotic resistant bacteria to wild ungulates. Methods and ResultsFaecal samples were collected from buffalo (n=35), wildebeest (n=40), zebra (n=40) and cattle (N=20) from Mikumi National Park, Tanzania (MNP), where cattle is prohibited and from Ngorongoro Conservation Area (NCA) where co-grazing is practiced. The number of coliforms and enterococci resistant to selected antibiotics was determined. Wild life generally harboured higher number of resistant Escherichia coli and Enterococci than cattle, but with no general influence in wild life of co-grazing with cattle. Vancomycin-resistant Enterococci were detected in wild life samples, and E.coli resistant to cefotaxime and enrofloxacin were observed among isolates from all wild life, but not from cattle. Culture independent estimates of the number of sulII gene copies obtained by qPCR did not differ between wild life from the two sample sites, while tetW was significantly higher in samples from MPN than from NCA. ConclusionsAntibiotic resistant bacteria were not more frequently found in ungulates grazing together with cattle than ungulates without this interaction. Significance and Impact of the StudyThis study did not indicate that transmission of antibiotic resistant bacteria is a frequent event following co-grazing of wild life and cattle.