Parapoxviral vulvovaginitis in Holstein cows

A group of Holstein first-calved heifers developed small pustules and ulcers on the vulva and in the vagina during the first 1–4 wk postpartum. The lesions varied from small red pinpoint foci to pustules and ulcers, 3–5 mm diameter. Some ulcers coalesced to form large ulcerated areas up to 15 mm diameter. In some animals, these ulcers progressed to become deep ulceration of the vaginal and vulvar mucosa with >50% of the mucosa involved. Vaginal biopsies from 4 heifers and vaginal individual swabs from 8 heifers for a combined sampling of 9 heifers were taken for clinical assessment. Six of the 9 heifers had parapoxvirus based on histopathology and/or PCR. Histologic examination of the biopsies of the pustules identified ballooning degeneration of the epithelium with degenerate epithelium containing eosinophilic intracytoplasmic inclusions consistent with a parapoxvirus in 3 of 4 biopsies. Testing for bovine herpesvirus 1, 2, and 4, bovine viral diarrhea virus, bovine papular stomatitis virus, and orf virus remained negative.