[Results of veterinary tumor research and their significance for practice]

Enzootic bovine leucosis and Marek's disease of fowl are the most important tumour diseases of farm animals, with the greatest repercussions on the national economy, today. Experimental findings obtained from either disease in recent years are reported in this paper, and an assessment is made of their importance to practice. In the context of enzootic bovine leucosis, particular reference is made to those findings which helped to establish the presence of virus infection, results by which the pathogen could be characterised, and to studies undertaken with the view to devising methods for virologico-serological diagnosis. In the context of Marek's disease, reference is made to virological, epizootiological, and diagnostic aspects, however, with emphasis being laid on possibilities for immunisation and, in that connection, on known fundamental concepts for successful immunoprophylaxis against that tumour disease.