Fetal alcohol effects in rats exposed pre- and postnatally to a low dose of ethanol.

Wistar rats were exposed pre- and/or postnatally to a low dose of ethanol (1 g/kg of body weight of dams/day) via maternal peroral intubation. This dose significantly increased the mortality rate (23 to 32% vs. 7% in controls) in offspring exposed to ethanol during pregnancy, with a continued postnatal exposure having no additional effect. However, offspring cross-fostered to dams that had been exposed to ethanol only during gestation (the offspring themselves never being directly exposed to ethanol) displayed an even greater (59%) mortality. Growth of the offspring was initially delayed, but 9 weeks after birth their body weight reached that of the controls. The two-way active avoidance test showed an impairment, compared with the controls, of learning and memory in both male and female adolescent (9-week-old) rats, as well as in male (but not in female) 5-month-old rats born of dams exposed to ethanol during gestation and lactation. In the group of male rats treated prenatally and postnatally with ethanol, 60% were "poor learners," compared with 33% in the control group. Results suggest that ethanol at a dose of 1 g/kg/day administered to dams during gestation and lactation produced growth and behavioral changes in the offspring.