Regulation of maternal behavior, social isolation responses, and postpartum estrus by steroid hormones and vaginocervical stimulation in sheep.

Periparturient ewes display several activities in addition to maternal behavior per se. They isolate themselves from the flock and, contrary to other mammals, do not show postpartum estrus. We investigated the possibility of a common hormonal control of maternal behavior, prepartum social isolation responses, and absence of postpartum estrus.