Recovery from experimentally induced problem-solving deficits in neonatal Peking ducklings as a function of environmental stimulation

Neonatal Peking ducklings were reared in 3 different environments containing varied light and sound stimulation. One group was exposed to the stimulative environment only during the last 3 prenatal days, 1 group was placed in the stimulative environment at the time of hatching, and the 3rd group was exposed to the stimulative environment both pre- and postnatally. No differences in performance in a detour learning task were noted between controls and experimentals from the 1st 2 groups (prenatal stimulation only and postnatal stimulation only); however, the group receiving both pre- and postnatal stimulation solved the detour task significantly faster than their controls. This learning improvement as a function of the stimulative environment represents a partial recovery from the deficit produced as a result of the experimental paradigm in which the shell covering the air space was replaced with clear plastic wrap, a procedure which has been shown to reduce oxygen consumption and lead to learning retardation.

Learning deficits in the neonatal Peking duckling produced by decreased oxygen consumption during late prenatal periods: a cautionary note

Neonatal Peking ducklings were tested in a detour problem-solving task following replacement of the shell overlying the air space of the egg on Prenatal Day 24 (total incubation period: 27 days) with a plastic wrap. This procedure, a common practice in behavioral embryology, resulted in a significant decrease in oxygen consumption, and a protracted retardation in the mastery of the learning task, with experimental ducklings solving the problem at a mean age of 5.27 days, compared with 2.32 days for controls. These results serve to underscore the problems that may be encountered as a result of any interference with the integrity of the egg during the prenatal period.