EFFECTS OF ALTERED OLFACTORY EXPERIENCES ON THE DEVELOPMENT OF INFANTRATS RESPONSES TO ODORS

A ''natural'' olfactory learning paradigm was used to assess the effec ts of an altered perinatal olfactory environment on the development of odor-elicited behavor in young rats. Infant rats (from 3 to 12 days o f age) reared by dams fed a eucalyptol-adulterated diet responded to t he odor of eucalyptol with high levels of activity, mouthing, and prob ing, and also demonstrated a marked preference for that odor in a two- choice situation (Experiment 1). The effects were observed only in pup s whose dam was fed eucalyptol-adulterated diet and were not observed in pups exposed to nonmaternal sources of odor. The intensity of behav ioral activity elicited by eucalyptol odor varied, to some extent, wit h the concentration of the eucalyptol in the dam's diet during prenata l exposure (Experiment 2). Cross-fostering revealed that these effects were due almost entirely to the pups' postnatal exposure to the eucal yptol odor (Experiment 3). These findings indicate that novel odors sp ecifically associated with the mother can gain control over orientatio n and ingestion-related behaviors. (C) 1996 John Wiley & Sons, Inc.