Enhanced intake of ethanol in preweanling rats following interactions with intoxicated siblings

Recently Hunt, Holloway, & Scordalakes (1999) described a novel procedure for examining how social interactions with an intoxicated sibling can enhance periadolescent rats' voluntary intake of ethanol. In the present series of experiments we extend these findings to preweanlings. In Experiment 1, same-sex sibling 16-day-olds were assigned to be either (a) a demonstrator that was administered 1.5 g/kg ethanol or water control or (b) an observer that was tested for ethanol intake following a brief interaction with the demonstrator. Observers interacting with EtOH demonstrators exhibited increased intake of ethanol relative to observers interacting with water demonstrators. In Experiment 2, subjects were 8, 12, or 16 days of age and at all ages, ethanol intakes increased following exposure to an intoxicated sibling. In Experiment 3, repeated exposures to ethanol demonstrators on days 12, 14, and 16 was found to promote ethanol intake after weaning (on postnatal day 22). Collectively these data indicate that exposure to ethanol cues in the context of home/social cues can lead to modifications in ethanol acceptance, and that repeated exposures to such cues during infancy can impact ethanol ingestion after weaning.