Survey for Antibodies to Bovine Leukemia Virus in Dairy and Beef Cattle in Japan

Abstract

A seroepidemiological survey for antibodies to bovine leukemia virus (BLV) in dairy and beef cattle in Hokkaido and in the Towada district was performed using BLV glycoprotein antigens by the immunodiffusion test. Ninety-four of 2878 sera (3.3%) from the 14 districts of Hokkaido were positive for BLV antibodies. In contrast, in the Towada district, where enzootic bovine leukosis has been previously reported, 363 of 1127 sera (32.2%) were reactive. The number of reactive samples varied from 6.9 to 52.7% in 13 pastures in the Towada district and the percentages increased gradually with age. No significant difference in lymphocyte counts between BLV antibody positive and negative beef cattle was found. Thirty sera from cattle with naturally occurring lymphosarcoma were also tested. The sera from the adult form of bovine lymphosarcoma reacted with BLV glycoprotein antigens, but the sera from the other forms of bovine lymphosarcoma did not.