Genital stimulation modifies behavior towards amniotic fluid in estrous ewes

Placentophagia in rabbits: incidence across the reproductive cycle

Rabbits show placentophagia at parturition, but the regulation of this behavior and its incidence across the reproductive cycle are unknown. By testing estrous, midpregnant, prepartum (day 1), and postpartum (days 1 and 5) food-deprived rabbits with liver and placenta, we found an absence or infrequency (<%) of placentophagia in the former three groups, an invariable occurrence at parturition, and a persistence into postpartum days 1 and 5 (50 and 48%, respectively). Most placentophagic females also ate liver on postpartum day 1, but not on postpartum day 5. In different food-deprived rabbits, tested every 2 hr with placenta and food pellets, placentophagia incidence was 20% at 8 hr prepartum, 100% at parturition, and 67 and 21% at 8 and 24 hr postpartum, respectively. Most placentophagic rabbits also ate food pellets in postpartum (but not in prepartum) tests. Results suggest that somatosensory, hormonal, or both factors of the peripartum period regulate placentophagia expression.

Establishment of maternal bonding and its mediation by vaginocervical stimulation in goats

To investigate the establishment of offspring recognition in mother goats, 11 females were subjected to two successive 5-min tests with their own kid and an alien, 2 h 30 min postpartum. All mothers accepted their own kid, while nine rejected the alien. This suggests that in goats, 2.5 h are sufficient for the development of an exclusive bond with the kid. We also studied the role of physiological factors mediating maternal bonding in this species. Eight of the nine goats that rejected alien kids were, therefore, submitted to 5 min of vaginocervical stimulation (VCS) immediately following the selectivity tests. Of these eight goats, five changed their behavior after VCS and accepted the alien kid (0/8 before VCS vs. 5/8 after VCS, p = 0.031). Thus, VCS appears to reduce rejection behavior towards alien kids while resulting in a significant increase in their rate of acceptance. Underlying physiological mechanisms by which VCS may act are discussed.