Serological evidence of the occurrence of enzootic bovine leukosis (EBL) virus infection in cattle in Tanzania.

Antibodies specific to bovine leukosis (leukemia) virus (BLV) were examined by enzyme-linked immunosorbent, assay (ELISA) in 2,849 serum sample from exotic/improved and indigenous cattle originating from 6 regions of Tanzania, 2,047 from dairy cattle and 802 from beef cattle. An overall infection rate (prevalence) of approximately 36% was detected. The infection rates were 41% and 21.4% in dairy and beef herds respectively. In the dairy herds the infection rate varied from herd to herd. The possible sources of infection and methods of spread within Tanzania are discussed.