Characterization of colostrum from dams of BLV endemic dairy herds.

•Provirus was detected in 69.23% of colostra, even in those with low antibody titers.•80% of provirus-positive colostra were from dams with high blood proviral load.•Colostrum proviral load was more than 100-fold lower than blood proviral load.•Consuming colostrum with infected-cells and a poor content of antibodies may be a risk.