Chronic ethanol exposure during late gestation produces behavioral anomalies in neonatal lambs.

A total of 45 pregnant ewes were assigned to one of three treatment groups: 1 g ethanol/kg maternal body weight (n = 18); pair-fed control (n = 15); and ad lib control (n = 12). Dosing started at gestational day (GD) 106, and was administered every other day until GD 134. Parturition occurred between GD 144 and 147. Analysis of the placentas indicated that ethanol exposure decreased cotyledon diameter and cotyledon weight compared to the control groups (p < 0. 05). At birth, lambs were given a Vigor Score and then behavior was assessed using a videotape monitoring system for 24 h. Offspring in the ethanol treatment group were significantly less vigorous at birth (p < 0.05). This finding reversed during the subsequent 24 h such that the ethanol-exposed lambs were significantly more active (p = 0.001) than the control lambs. Morphometric and histologic examination of the cerebral cortex and hippocampus revealed no differences amongst the three treatment groups. Collectively, the data demonstrate that moderate ethanol exposure during the third-trimester equivalent of gestation can produce placental dysmorphology and postnatal behavioral anomalies in neonatal lambs in the absence of gross neurologic injury.