Comparative Aspects of Bovine Leukemia

Abstract

The discovery of particles resembling mouse leukemia virus in cow's milk from a herd with a high incidence of leukemia and in lymph node cells of leukemic cattle and the finding of similar viruslike particles in human leukemic plasma and in pasteurized market milk are disquieting developments calling for intensive investigation to determine the biologic significance of the particles. The features of bovine leukemia are reviewed, and experiments are described which suggest the presence of a “resistance factor” in leukemic milk.