Mechanism of Seasonality in Japanese macaques (Macaca fuscata)

日本猕猴（Macaca fuscata）的季节性机制

基本信息

批准号：
11833008
负责人：
HAMADA Yuzuru
金额：
$ 1.66万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11833008/
关键词：
Seasonality Seasonal Breeding Body Fat Japanese macaque Adolescence Body Composition Leptin IGF- 1 ニホンザル(Macaca fuscata fuscata)

项目摘要

Seasonality in Japanese macaques (fu) was examined by the comparison with long-tailed macaques (fa) which are close to fu and without clear seasonality. Seasonality is expressed in nutritional and reproductive states. Fat mass was measured with Dexa to elucidate variability profile (sex difference, age change, and seasonality). Statistical analyses proved the utility of such indirect fat indicators as body weight (BW), physique index, and skinfold. Standard weights are 8 and 12 kg in adult fu females and males respectively, and fat mass is about 10% of BW. No immature individual with more than 10% of fat was found in the two species. Adults accumulate fat rapidly in fa, but not in fu. It is considered that the seasonal loss of fat in fu prevents the excessive accumulation. Time-series analysis was applied on the longitudinal BW and endocrinological data. BW seasonal cycle is not greatly influenced by reproduction, but mainly by nutrition. Fat mass contributes to the BW seasonal fluctuation by about 40%, but the increase and decrease of reproductive organs do not. Lean phase in BW cycle is longer in fu female than in male, reflecting the sex difference in feeding behavior or in the rate of assimilation. The nutritional state in autumn appears to determine the rate of conception. Some nutritional signal (e.g., blood glucose) is considered to stimulate the endocrinological system of reproduction. Leptin, although it showed seasonality, was not considered to participate in that function. The convenient method for steroid hormones using fecal samples is expected to apply on wild monkeys. Direct relationships have been reported for some cercopithecoids, that is the amelioration in nutritional state initiates breeding. However, fu has developed the additional safeguard endogenous calendar mechanism, because the survival of winter appears more important than reproduction.

通过与接近 fu 但没有明显季节性的长尾猕猴 (fa) 进行比较，研究了日本猕猴 (fu) 的季节性。季节性表现为营养和生殖状态。使用 Dexa 测量脂肪量以阐明变异性（性别差异、年龄变化和季节性）。统计分析证明了体重（BW）、体质指数、皮褶等间接脂肪指标的实用性。成年fu女性和男性的标准体重分别为8公斤和12公斤，脂肪量约为体重的10%。两个物种中均未发现脂肪含量超过10%的未成熟个体。成年人在fa中脂肪积累很快，但在fu中则不然。人们认为，府中脂肪的季节性流失可以防止脂肪过度积累。对纵向体重和内分泌数据进行时间序列分析。 BW季节周期受繁殖影响不大，而主要受营养影响。脂肪量对体重季节性波动的影响约为40%，但生殖器官的增减则无影响。雌性体重周期的瘦肉期长于雄性，反映了摄食行为或同化率的性别差异。秋季的营养状况似乎决定了受孕率。一些营养信号（例如血糖）被认为可以刺激生殖内分泌系统。瘦素虽然表现出季节性，但不被认为参与该功能。使用粪便样本检测类固醇激素的便捷方法预计将适用于野生猴子。据报道，某些鹿类动物有直接关系，即营养状态的改善引发繁殖。然而，Fu开发了额外的保障内生历法机制，因为冬天的生存显得比繁殖更重要。