Maternal and affective behaviors of lactating rats reared in overlapping litters

Publication date: Available online 16 April 2014 Source:Journal of Physiology-Paris Author(s): Natalia Uriarte , María Victoria Fernández , Daniella Agrati , María José Zuluaga , Marcela Ferreño , Annabel Ferreira Postpartum mating in rats gives rise to complex family units consisting of the mother and two overlapping litters. As a consequence, newborn pups of the second litter, since the moment they are born, acquire experience not only from interaction with the mother and age-matched littermates but also from interaction with older siblings. Newborn pups reared in overlapping litters (OLs) receive a different pattern of maternal stimulation compared to those reared in single litters (SL: one litter of same aged pups), as the mothers reduce some maternal behavior components and juvenile pups from the first litter develop maternal behavior. Since there is strong evidence showing that variations in maternal behavior are transmitted throughout generations, we hypothesized that the altered pattern of maternal stimulation received by OL reared females would modify their behavior during motherhood. To test this hypothesis maternal behavior, maternal aggression and experimental anxiety of dams reared under OL and SL conditions during the first postpartum week were compared. No differences were found between the groups in their maternal behavior and aggression. This result may be explained by the maternal behavior of the juveniles that could compensate for the deficit...
Source: Journal of Physiology Paris - Category: Physiology Source Type: research