Relevant oncogenic viruses in veterinary medicine: original pathogens and animal models for human disease.

Oncogenic viruses are important pathogens in farm and companion animals. These original pathogens are classified in various virus families, such as Retroviridae, Papillomaviridae, and Herpesviridae. Besides a role as pathogens for its original host, animal viruses serve as valuable models for viruses affecting humans, such as hepatitis B virus, and issues of immunity, therapy, but also basic pathophysiological mechanisms, can often only be addressed in those animal systems.