Maternal and nutritional contributions to infant rats' activational responses to ingestion

Abstract

Infant rats deprived of food, maternal care, and the opportunity to suckle display a dramatic behavioral activation and vigorously ingest when provided milk through oral cannulas. These experiments assessed which components of deprivation are important in producing these responses to milk. Nutritional deprivation alone, with or without the presence of an active maternal female, appears to be sufficient to produce ingestion. Behavioral activation, on the other hand, appears to require both nutritional deprivation and deprivation from a maternal female. The effect of maternal stimulation on later behavioral reactivity was not a function of the pups' opportunity to suckle. However, active maternal stimulation was more effective in preventing activation than was passive maternal stimulation (e.g., thermotactile and olfactory stimulation). Stimulation provided by an active, nonlactating mother was effective in preventing behavioral activation, but the effect was short-lived, lasting only 2 hr after the pup was removed from the mother's care. This series of studies thus reveals that identified components of maternal separation have dissociable effects on appetitively motivated behaviors in infant rats.

Maternally directed orienting behaviors of newborn rats

“…Other studies of behavioral activation in older separated pups suggest that deprivation of behavioral interaction with the dam, rather than nutrition, may be the relevant aspect (Bornstein, Terry, Browde, Assimon, & Hall, 1987;Hofer, 1973). Further experiments with the addition of a nutritionally deprived group with access to the dam are required.…”

Ontogeny of ingestive behavior

“…But, as Hall (1979b) noted, deprivation also involves maternal separation, absence of maternal care, and deprivation of the opportunity to receive oral stimulation from suckling. His laboratory subsequently showed that the maternal aspects of deprivation were not necessary for the increase of OC intake (Bornstein, Terry, Browde, Assimon, & Hall, 1987).…”

Guidance and differentiation of maternally directed orienting behaviors: Probing the origins of filial attachment

“…Thus, ongoing experience of the larger interaction with the dam is necessary to maintain nipple grasp competence, suggesting that at these ages, NG and MDOBs are not fully differentiated. In the second study, Bornstein, Terry, Browde, Assimon, and Hall (1987) acutely deprived 6 day old pups of the mother and milk separately. Pups that were prevented from suckling ingested more milk through a cannula, whereas pups that were deprived of both milk and the nonsuckling interaction with the dam became generally behaviorally activated as well.…”