Sexual behavior in the female rat is a highly motivated behavior first displayed during adolescence, a developmental period when neural circuits underlying motivation are not mature. This study characterizes the natural development of sexual motivation and behavior of female rats. We compared the incentive value of the male for mid-adolescent (PNDs:39-43), late adolescent (PNDs:49-53), and adult (PNDs:90-115) cycling females, using a male–female preference task and an ultrasonic vocalization emission test following exposure to a male or female stimulus animal. Furthermore, display of sexual and social behaviors during an interaction with a male or a nonreceptive female was assessed. Mid-adolescent rats exhibited a reduced preference for the male than adults and performed less attempts to access the male. Unlike late adolescent and adult females, mid-adolescent rats did not increase their ultrasonic vocalization emission after interacting with a male relative to a female. Although most of the sexual behavior did not differ between groups, mid-adolescent females showed lower lordosis magnitude and higher levels of play and social investigation during a sexual interaction, giving rise to a unique behavioral profile. Present results indicate that the sexual behavior repertoire is fully displayed by mid-adolescence, but sexual motivation is low and increases into late adolescence.

中文翻译：

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骑自行车的雌性大鼠在整个青春期的性动机增加

雌性大鼠的性行为是在青春期首次表现出的高度动机行为，这是一个发育时期，潜在动机的神经回路不成熟。这项研究描述了雌性大鼠性动机和行为的自然发展。我们使用男性-女性偏好任务和暴露于雄性或雌性刺激动物后的超声波发声发射测试。此外，还评估了在与男性或不接受女性的互动过程中表现出的性和社会行为。与成年大鼠相比，青春期中期大鼠对雄性的偏好降低，接近雄性的尝试也更少。与青春期晚期和成年女性不同，青春期中期的大鼠在与雄性相对于雌性互动后并没有增加它们的超声波发声发射。尽管大多数性行为在各组之间没有差异，但处于青春期的女性在性互动过程中表现出较低的脊柱前凸幅度以及较高的游戏和社会调查水平，从而产生了独特的行为特征。目前的研究结果表明，性行为曲目在青春期中期充分表现出来，但性动机低下并在青春期后期增加。青春期中期的女性在性互动过程中表现出较低的脊柱前凸幅度和较高的游戏和社会调查水平，从而产生了独特的行为特征。目前的研究结果表明，性行为曲目在青春期中期充分表现出来，但性动机低下并在青春期后期增加。青春期中期的女性在性互动过程中表现出较低的脊柱前凸幅度和较高的游戏和社会调查水平，从而产生了独特的行为特征。目前的研究结果表明，性行为曲目在青春期中期充分表现出来，但性动机低下并在青春期后期增加。