Maternal behavior priming in virgin and caesarean-delivered Long-Evans rats: effects of brief contact or continuous exteroceptive pup stimulation

The effects of 8 days of prior exposure to pups (Priming) in the form of continuous exteroceptive (smell, sight and sound), or 15 min/day physical access (taste and touch possible) stimulation on the subsequent latency to become maternal during cohabitation with pups (concaveation) was studied in Long-Evans female rats. Brief daily access was effective in hastening the onset of maternal behavior only in those virgins which engaged in pup licking during Priming and in maintaining short-latency maternal responsiveness only in those day 21 pregnancy-terminated, thelectomized rats which initiated maternal behavior during Priming. Exteroceptive stimulation was ineffective in both virgins and caesarean-sectioned rats. These findings stress the importance of physical interactions with pups (unrelated to nipple stimulation) for the development of nurturance.