Plasma bovine placental lactogen concentration throughout pregnancy in the cow: relationship to stage of pregnancy, fetal mass, number and postpartum milk yield.

birth weight blood plasma cows embryo transfer feto foetal death foetus gestation gestation multiple hormonas hormone hormones lactation milk yield mort du foetus muerte fetal multiple births peso al nacimiento plasma sanguin pregnancy rendement laitier rendimiento lechero secretion transferencia de embriones transfert embryonnaire vaca vache