Occurrence of different subgroups of avian leukosis virus in finnish poultry

Abstract

Ten Finnish breeding flocks were investigated for occurrence of avian leukosis virus and antibodies. The results show that field isolates representing all 4 main subgroups, A, B, C, and D, of avian leukosis virus have been identified. Antibodies to these subgroups are widespread in the country. Within 5 of the flocks antibody response to all 4 subgroups was found simultaneously, and there were individual chickens that carried antibodies against 2, 3, and in 2 cases, even, all 4 subgroups at the same time.