Characterization of copulatory behavior in female mice: evidence for paced mating.

In this study we characterized female mouse sexual behavior using a pacing paradigm similar to that used to evaluate sexual behavior in female rats. A pacing chamber was designed for use with mice and we compared the sexual behavior of female mice that were tested in both pacing and nonpacing paradigms and under different hormone conditions. We found that, like rats, female mice do pace their copulatory behavior by altering the temporal sequence of copulatory events. Female mice take longer to return to the male after an ejaculation, compared to either a mount or intromission. However, it is still unclear if female-paced mating serves the same functions as it does in female rats. More work is needed to confirm that paced mating induces hormonal changes needed for pregnancy as is the case in rats.