Swimming and self grooming development of pups nursed by neonatally underfed rats

Swimming and self-grooming development were analyzed in experimental animal s nursed by neonatally underfed dams by a method including the deprivation of both food and sensory cues which provoke long-term altered maternal beha vior. Experimental animals obtained from these dams manifested a significan t retardation in physical growth, as evidenced by a decrease in body weight and a 1-day delay in ear and eye-opening, as well as a significant delay i n swimming ability, escaping from the water and an increase in self-groomin g behavior. These alterations of experimental animals may be presumably rel ated with the carelessness in maternal care and altered somatosensory stimu lation given by the neonatally underfed dams to her experimental pups. Data suggest that the poor somatosensory stimulation given by the mother to her pups, the reduced early social interaction or the motivational stage of pu ps may be important determinants for the development of brain mechanisms un derlying reflex activity of the progeny.