A free-operant olfactory choice procedure to assess preference for social and nonsocial scents in female rats

Abstract

Rats are a social species, often used as a research model to study social behavior. However, isolating the factors (i.e., environmental stimuli, experiences with social interactions, novelty, etc.) that influence rats' social behavior can be difficult in many existing social choice assessments. A procedure that may help researchers investigate these variables more systematically is the olfactory choice procedure. The present set of experiments used a free-operant olfactory choice procedure to assess individually housed female rats' preference for social and nonsocial scents. In Experiment 1, rats ran daily sessions in which a response to a nose-poke port produced either a social or nonsocial scent. A response to a second nose-poke port produced a control scent. In Experiment 2, the same female rats could respond in one nose-poke port to produce a social scent and in a second port to produce a nonsocial scent. The results from Experiment 1 indicate that rats prefer social and nonsocial scents over a control scent and that this preference persists across a location reversal and 100+ daily sessions. Although there were individual differences, group results from Experiment 2 suggest that rats prefer social and nonsocial scents relatively equally.