Bovine Papillomaviruses

• 2 groups:

1. Fibropapillomas: viral DNA sequences, but no virus found
2. Epithelial Papillomas: virus found

• Calves most commonly affected
• Usually resolves spontaneously
• Can undergo malignant transformation to alimentary carcinomas
  • Usually concurrent with grazing bracken (co-carcinogen) and ingesting quercetin (immunosuppressant)
• Can cause squamous cell carcinoma of the eye in Hereford cattle, where UV light acts as the co-carcinogen

Papillomatosis

• Caused by Bovine Papillomaviruses|bovine papilloma virus-4.
• Usually affects pedunculated structures in reticulum/rumen of cattle.

Viral papillomas

in the pharynx