Variations of response of cattle to experimentally induced viral papillomatosis.

The common bovine papilloma virus type 1 has been widely used to stimulate basic research on papilloma viruses involved in some cancers of mankind. The usually benign neoplasms of cattle caused by bovine papilloma viruses are frequent clinical problems for veterinarians. Approximately 240 experimentally induced cutaneous fibropapillomas on 8 susceptible calves had a uniform appearance of initial growth. Their size and duration ranged from about 2 months to nearly 3 years but were similar for the multiple papillomas of each calf. Sequential biopsies were done to examine the histologic changes and existence of viral antigen. Veterinarians in practice may encounter the common fibropapillomas caused by bovine papilloma virus 1 and 2 as well as papillomas with no fibromatous element. These types may develop on teats of cows in some herds. Interdigital papillomas cause a problem in some dairy herds and a virus suspected but not yet found. Prophylactic vaccination with a formalin-killed vaccine will protect against infection with bovine papilloma virus 1 and 2.