[Studies on biological characterization of mammary tumours of the sprague-dawley-rat in the syngeneic tumour-host system. I. Spontaneous primary mammary tumours and tumours induced by oral and intravenous application of DMBA (author's transl)].

Spontaneous and DMBA-induced mammary tumours of a Sprague-Dawley inbred line reared in Berlin-Buch are described. The incidence of spontaneous tumours was 14.3%, of chemically induced tumours 43.6% of all the animals tested. 5 different schedules of application proved superior to the oral route with regard to dose, mortality and tumour incidence. 87.2% of the carcinomas and 12.8% of benign tumours following DMBA treatment developed in the region of the mammary glands.