Commonality among rats in production of reward and nonreward odors

Male and female test rats acquired a patterned response (fast on reward trials, slow on frustrative nonreward trials) in a runway based on differential odors excreted by donor rats during prior rewarded and nonrewarded placements in the goalbox. Initially, donor-test rat pairs were identical: A randomly selected, same-sex donor preceded the same test subject on each trial. In subsequent phases of the study, donors were interchanged for test rats, both within and between gender categories. Response patterning changed negligibly when the donor-test pairs were altered, suggesting a high degree of commonality among rats in odor excretions following reward and frustrative nonreward treatments.