[Experimental induction of lympholeukemia in calves by a purified preparation of bovine leukemia virus].

The leukemogenic properties of bovine leukemia virus (BLV), isolated from blood plasma, milk and short-term cultures of blood-circulating leukocytes were studied. A complex life-time examination of 14 calves inoculated with a preparation of BLV established leukemia in 4 animals; it was suspected in 3 calves. By the present time leukemia has been morphologically established in 6 out of 13 calves and one was a suspect. Positive results point directly to the viral etiology of bovine leukemia.