Proviral load and antibody titer in two experimentally challenged cattle. Two BLV-negative one-year-old Holstein-Friesian cattle (K576 and K577) were experimentally challenged subcutaneously with 0.5 ml of blood obtained from BLV-seropositive Japanese Black cattle. Blood and serum samples were obtained weekly for 10 weeks after the first inoculation with infected blood. BLV proviral loads were measured by BLV-CoCoMo-qPCR. Anti-BLV antibodies were detected by PHA and ELISA. Graphical representations of proviral load, ELISA S/P values, and PHA titer are shown.