In contrast, Schneider et al. (1981) observed
that cows serviced very late after calving (93 ± 17 d)
had lower fertility than cows serviced earlier (72 ± 18
d). The maximum VWP in the present study was 80 d
postpartum, so the efficacy of a VWP greater than 80
d postpartum is subject to greater uncertainty because
of extrapolation.