Importance of mother/young contact at parturition and across lactation for the expression of maternal behavior in rabbits

Abstract

We prevented mother/pup contact at parturition or across early or midlactation to investigate the importance of such interaction for maintaining maternal behavior in rabbits. When pup contact was prevented across lactation Days 1–7 or 11–17 (by anesthetizing multiparous mothers during the oxytocin‐induced milk letdown; Experiment 1), nursing incidence was reduced to 40% and 83%, respectively, on the day following anesthesia withdrawal. Both groups also showed a decreased milk output, long latencies to initiate nursing, and several entrances into the nest box not associated with nursing. In Experiment 2 we prevented mother/litter contact at parturition to determine the specific role of pup contact at this time. We found a reduction in the incidence of nursing on postpartum Day 1 from 80% (in control primiparous mothers) to 33%. By contrast, 100% of both deprived and control multiparous mothers displayed nursing on Day 1. These mothers also showed the unusual behaviors found in Experiment 1 and an extemporaneous nest‐building. We conclude that: (a) mother/young contact at parturition is crucial for establishing maternal responsiveness in primiparous does, (b) the experience acquired by raising a previous litter allows the retention of maternal responsiveness despite a lack of pup contact at parturition, (c) maternal responsiveness is maintained across early lactation by daily interaction with pups, and (d) interaction with pups across midlactation allows the finely tuned display of maternal behavior. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 32: 101–111, 1998

Pharmacological Evidence that Prolactin Acts from Late Gestation to Promote Maternal Behaviour in Rabbits

“…This peripartum period is important for establishing the onset of maternal behaviour and for beginning the transition referred to above. We have shown that the primiparous mother's interaction with her pups during this period is crucial for her readiness to enter the nest on the following days and, deprived of this interaction, mothers are hesitant to enter the nest and nurse the litter (13). Mothers that are under anaesthesia while suckled daily during the ®rst week show even more drastic de®cits in maternal behaviour when allowed to nurse freely on day 8 than mothers prevented from interacting with their pups only at parturition (13).…”

“…In rabbits, the mother/young interaction has been restricted to a minimum: a 3±5 min bout of nursing each day (1,11,12). Yet, mother rabbits rely on this brief contact with their litter (at parturition and across early lactation) for the maintenance of a normal maternal behaviour (13). Such contact during nursing stimulates the production/secretion of hormonal factors (14) that may, in turn, act on the mother's brain to promote her maternal behaviour.…”

“…Such contact during nursing stimulates the production/secretion of hormonal factors (14) that may, in turn, act on the mother's brain to promote her maternal behaviour. If mother/young contact is prevented at parturition, the release of hormonal factors in response to the ®rst suckling is eliminated and primiparous mothers display an aberrant maternal care at the next nursing session and for several days thereafter (13). Moreover, if awake contact with the litter is prevented during nursing (through anaesthesia) across the ®rst week of lactation, maternal behaviour is de®cient for many days (13).…”

“…If mother/young contact is prevented at parturition, the release of hormonal factors in response to the ®rst suckling is eliminated and primiparous mothers display an aberrant maternal care at the next nursing session and for several days thereafter (13). Moreover, if awake contact with the litter is prevented during nursing (through anaesthesia) across the ®rst week of lactation, maternal behaviour is de®cient for many days (13). These de®cits in maternal behaviour may be a consequence of reduced prolactin secretion in response to suckling (milk output is decreased in these females despite oxytocin injections), and/or the lack of sensory stimulation from suckling by the young.…”

Differences in placentophagia in relation to reproductive status in the california mouse (Peromyscus californicus)

“…This behavior has been proposed to enhance maternal responsiveness, potentially by priming the mother’s brain through the diverse hormonal content found in placenta (Kristal, DiPirro, & Thompson, 2012; Melo & González-Mariscal, 2003). Studies on rabbits ( Oryctolagus cuniculus L.; González-Mariscal, Melo, Chirino, Jiménez, Beyer, & Rosenblatt, 1998), rats ( Rattus norvegicus ; Kristal, Whitney, & Peters, 1981a), sheep ( Ovis aries ; Lévy & Poindron, 1987; Lévy, Poindron, & Le Neidre, 1983), and dogs ( Canis lupus familiaris ; Abitbol & Inglis, 1997) have shown that the presence of amniotic fluid on newborns enhances mother-offspring bonding and advances the onset of maternal behaviors. In a similar manner, virgin female rats, which normally do not express maternal behavior spontaneously, show increased attraction to pups and decreased latency for maternal sensitization when presented with unrelated, placenta-smeared pups as compared to unrelated pups that were not treated with placenta (Kristal et al, 1981a).…”