Maternal Responsiveness of Neonatally Undernourished and Sensory Stimulated Rats: Rehabilitation of Maternal Behavior

Abstract

The interaction between neonatal food deprivation and early sensory stimulation on four maternal behavioral components of Wistar strain rats was investigated. Dams neonatally underfed by daily mother-litter separation (Experiment 1), showed significant reductions in nest-rating and nursing time as well as increased retrieving latencies and selfgrooming responses compared to controls. Mothers which were neonatally undernourished by the nipple-ligation of their mothers (Experiment 2), exhibited less alterations in nest ratings, nursing time and retrieving latencies with no significant differences in the frequency of self-grooming responses, in comparison to controls. Neonatal handling and the exposure to a sensory enriched environment in Experiment 1, ameliorated most of the alterations of neonatally underfed mothers. Moreover, in Experiment 2, the increase in the neonatal sensory stimulation only improves nest ratings performance without consistent effects upon other maternal behavioral responses. Data suggest that sensory stimulation at critical stages of brain ontogeny is able to compensate long-term maternal behavioral deficiencies associated to a severe neonatal undernutrition (Experiment 1), with variable effects following a mild food intake deprivation (Experiment 2).

Keywords:

• Early undernutrition
• Maternal responsiveness
• Sensory cues