The aim of the present investigation was to get further information about obligate aerobic and facultatively anaerobic bacterial communities of the intact and Wohlfahrtia magnifica infested vulval region of sheep. The numbers of aerobic and facultatively anaerobic microorganisms were lower in samples taken from uninfested mucous membrane and myiatic wounds as well as in the wound fluid as compared to samples originating from the uninfested skin surface. Gram-negative bacteria belonging to the family Enterobacteriaceae were isolated only from the skin and mucous membrane of uninfested sheep. Gram-positive microorganisms dominated in all samples. The ratio of facultatively anaerobic bacteria was higher than 80% in the sample taken from a lesion containing third instar Wohlfahrtia larvae and in the wound discharge collected from a vulval wound free of maggots. It is suggested that there is a shift in the composition of the bacterial communities of vulva as staphylococci disappear from the wounds due to the presence of Wohlfahrtia larvae.