Ulcerative vulvitis and balanitis in sheep flocks.

Outbreaks of ulcerative vulvitis and balanitis occurred in three commercial sheep flocks in England and Wales. Between 29 and 44 per cent of the ewes were affected; most of the lesions resolved in three weeks. Pathogens such as mycoplasmas, which have previously been associated with these conditions, were not detected despite using improved laboratory techniques. In one of the flocks, ovine herpesvirus type 2 was detected by pcr in the blood of two acutely affected ewes, from the vulval ulcers of one of them, and from the penis of an affected ram.