PAPILLOMAVIRUS-INDUCED DERMATOFIBROMA IN CATTLE FOLLOWING TUBERCULIN TESTING

Papillomavirus was identified in two fibromatous dermal nodules which were representative of those present in the caudal fold skin of the ta il in 25 of 145 beef cattle tuberculin tested 3 months earlier. Bovine warts were endemic on the property and it is hypothesised that the pa pilloma virus was introduced intradermally by a virus-contaminated tub erculin syringe. At palpation, the well-circumscribed hard nodular les ions were atypical of the diffuse caudal fold swelling usually present in reactions to tuberculin. Provided tuberculin testing officers are aware of the risk of fibroma and papilloma induction by transmission o f papillomavirus, and they are careful to prevent equipment coming int o contact with warts at time of inoculation, this source of inaccuracy may be avoided.