Male-produced postejaculatory 22-kHz vocalizations and the mating behavior of estrous female rats.

The role of male-produced 22-kHz postejaculatory vocalization in the mating patterns of estrous female rats was investigated by monitoring the distance maintained by the females from the male following ejaculation in the presence and absence of these signals. All females were tested with tethered muted males (with and without tape-recorded 22-kHz vocalizations presented after ejaculation) and with tethered intact vocalizing males. Previously demonstrated findings of an increase in preejaculatory darting activity in the presence of intact vocalizing males were confirmed, but no evidence of an effect of postejaculatory vocalizations on the distance that the female maintained from the male was found. Thus, these results do not support the hypothesis that the postejaculatory 22-kHz vocalizations function to influence the female to avoid contact with the male during the postejaculatory refractory period.