Role of the main olfactory system in recognition between individual spiny mice

Recognition between spiny mice requires a period of exposure to learn the olfactory cues of individual conspecifics that can serve as recognition signatures in subsequent discrimination. Animals received nasal irrigations of zinc sulfate to disrupt sensory input to the main olfactory system (MOS) either prior to the 9-day exposure period (Experiment 1) or immediately after the exposure period (Experiment 2). Animals rendered anosmic by zinc sulfate did not show evidence of recognition as defined by huddling preferences. In contrast, animals who received irrigations of saline were able to preferentially huddle with their cagemate who they had been housed with during the exposure period. The results suggest that the MOS is necessary in mediating behavioral discrimination between conspecifics.