Effects on offspring behavior of parental early drug experience and cross-fostering

Abstract

Albino rats received a daily subcutaneous injection of trifluoperazine (0.33 mg/kg) from days 5 to 30. This group was undisturbed until breeding. Some of the offspring of male and female drug animals were cross-fostered at birth to mothers of the same group as the biological mother; others were cross-fostered to mothers of the group other than the biological mother; others stayed with the biological mother. Offspring received no experimental treatments nor drug administrations before being trained on avoidance conditioning beginning at 75 days of age. The major effects analyzed were Drug, Mothering and the Drug × Mothering interaction. This study reconfirmed the finding that a chronic drug experience in the infancy of albino rats detrimentally affects the learning ability of subsequent undrugged offspring. No support was obtained for the possibility that cross-fostering significantly affected offspring learning ability. There were small differences within the water and drug groups regardless of the rearing mother, but major differences were obtained between groups attributable to the drug, non-drug dimension. Additional research is required to uncover the mechanism underlying the cross-generational effect replicated in this study.