Ziegler T, Hodges K, Winkler P, Heistermann M
Department of Reproductive Biology, German Primate Center, Göttingen.
Am J Primatol. 2000 Jun;51(2):119-34. doi: 10.1002/(SICI)1098-2345(200006)51:2<119::AID-AJP2>3.0.CO;2-O.
To date, it is not known whether the seasonal occurrence of sexual behavior and mating in free-ranging Hanuman langurs at Ramnagar, Nepal, is correlated with seasonal changes in female ovarian function, and, if so, which factor(s) triggers the onset of the reproductive period. Using noninvasive fecal hormone analysis in combination with behavioral observations, this study was carried out to: 1) investigate and characterize seasonal patterns of ovarian cyclicity and timing of conception in wild langur females living in a highly seasonal habitat; and 2) examine the relationship between seasonal patterns of ovarian cyclicity, behavioral estrus, and female physical condition. Behavioral data and fecal samples were collected during a total period of 14 months from nine females living in a multi-male group. Physical condition of the females was assessed monthly by visual inspection, using a seven-fold scale. Ovulatory cycles and timing of conceptions were identified by the measurement of immunoreactive pregnanediol glucuronide (iPdG) in extracted feces. Hormone profiles in individual females revealed a clearly seasonal distribution in the occurrence of ovulatory cycles, which were restricted to the period from July to October. The distribution of female estrus behavior showed a similar seasonal pattern, and in total 88.2% of all estrus periods observed in the focal females were accompanied by ovulation. Onset of ovarian cycles as well as mating activities were strongly correlated with the onset of the rainy season. Females conceived, on average, in their second ovulatory cycle (pregnancy length: 211.6 +/- 3.4 days), with timing of conception being confined to the months when animals showed an improved physical condition. Collectively the present data clearly suggest that in seasonally-breeding langurs at Ramnagar, ecological conditions (rainfall, food availability, and quality) influence the onset of ovulations and timing of conceptions.
迄今为止，尚不清楚尼泊尔拉姆纳加尔自由放养的哈努曼叶猴性行为和交配的季节性发生是否与雌性卵巢功能的季节性变化相关，如果相关，是哪些因素触发了繁殖期的开始。本研究结合行为观察，采用非侵入性粪便激素分析方法，旨在：1）调查和描述生活在高度季节性栖息地的野生叶猴雌性卵巢周期性和受孕时间的季节性模式；2）研究卵巢周期性、行为发情期和雌性身体状况之间的关系。在14个月的时间里，从一个多雄群体中的9只雌性叶猴收集了行为数据和粪便样本。通过目视检查，每月使用七分量表评估雌性叶猴的身体状况。通过测量粪便提取物中的免疫反应性孕二醇葡萄糖醛酸苷（iPdG）来确定排卵周期和受孕时间。个体雌性叶猴的激素谱显示排卵周期的发生有明显的季节性分布，仅限于7月至10月。雌性发情行为的分布也呈现出类似的季节性模式，在重点观察的雌性叶猴中，观察到的所有发情期中有88.2%伴有排卵。卵巢周期的开始以及交配活动与雨季的开始密切相关。雌性叶猴平均在第二个排卵周期受孕（妊娠期：211.6 +/- 3.4天），受孕时间局限于动物身体状况改善的月份。总体而言，目前的数据清楚地表明，在拉姆纳加尔季节性繁殖的叶猴中，生态条件（降雨、食物供应和质量）会影响排卵的开始和受孕时间。
