Wilson Mark E, Walker Margaret L, Gordon Thomas P
Yerkes Regional Primate Research Center, Emory University, Atlanta.
Am J Primatol. 1984;7(1):21-26. doi: 10.1002/ajp.1350070105.
Young, sexually mature female rhesus monkeys copulate on more days prior to conception than do older females, and this prolonged discrete mating period is associated with an earlier rise in serum estradiol prior to the first ovulation of the breeding season. The influence of repeated ovulatory cycles and the presence of a suckling infant on the copulatory patterns were examined in two separate analyses. Extending previous work, young, nulliparous females copulated on more days at the first ovulation of the breeding season than did older, multiparous females. However, the duration of the copulatory period at the second ovulation of the breeding season was similar and significantly shorter for both age groups. Furthermore, the presence of a suckling infant did not influence the duration of the mating periods in adult, multiparous females. The onset of copulatory behavior for all females was associated with serum estradiol concentrations of approximately 90 pg/ml, indicating that the age and cycle differences in the duration of the copulatory periods are due to the time course of serum estradiol prior to ovulation. A separate, longitudinal analysis of the duration of the mating period associated with the first ovulation of three successive breeding seasons indicated that females copulated on more days during their first ovulatory cycle of their first breeding season. These data indicate that the copulatory interval is longer for females during the first ovulation of the breeding season, and this pattern is accentuated in young, sexually mature animals.
性成熟的年轻雌性恒河猴在受孕前进行交配的天数比年长雌性更多，并且这种延长的离散交配期与繁殖季节首次排卵前血清雌二醇的提前升高有关。在两项单独的分析中研究了反复排卵周期和哺乳婴儿的存在对交配模式的影响。在先前工作的基础上，年轻的未生育雌性在繁殖季节首次排卵时交配的天数比年长的经产雌性更多。然而，在繁殖季节第二次排卵时，两个年龄组的交配期持续时间相似且显著缩短。此外，哺乳婴儿的存在并不影响成年经产雌性的交配期持续时间。所有雌性的交配行为开始都与血清雌二醇浓度约90 pg/ml相关，这表明交配期持续时间的年龄和周期差异是由于排卵前血清雌二醇的时间进程。对连续三个繁殖季节首次排卵相关的交配期持续时间进行的一项单独纵向分析表明，雌性在其第一个繁殖季节的第一个排卵周期内交配的天数更多。这些数据表明，在繁殖季节首次排卵时雌性的交配间隔更长，并且这种模式在年轻的性成熟动物中更为明显。
