圈养林麝社会等级与粪样类固醇激素水平的关系

动物社群的社会等级可对个体的资源分配、社群稳定及个体的行为对策产生重要影响,圈养动物的类固醇激素水平与饲养管理有关,可反映动物的社群紧张水平。深入理解圈养动物的社会等级与其类固醇激素水平的关系是进行濒危动物迁地保育和成功驯养的基础。2018年6月15日—8月15日,用焦点取样法对四川马尔康林麝繁育场的25头林麝进行了冲突行为取样及社会等级计算,采用放射免疫分析法检测了同期粪样的类固醇激素水平,分析了林麝社会等级与粪样皮质醇、睾酮及雌二醇水平的关系。结果表明:低等级雌麝的雌二醇水平(289.037±59.710 pg·g^-1,n=11)显著高于高等级雌麝(45.670±27.283pg·g^-1,n=6)(P<0.05),低等级雄麝的睾酮水平(3.863±1.538 ng·g^-1,n=3)和高等级雄麝(8.017±1.295 ng·g^-1,n=5)无显著差异(P>0.05);低等级雄麝(37.891±7.564 ng·g^-1,n=3)和雌麝(37.262±1.544 ng·g^-1,n=11)的皮质醇水平与高等级雄麝(29.947±2.441 ng·g^-1,n=5)及雌麝(37.478±4.628 ng·g^-1,n=6)间的差异不显著(P>0.05)。不区分性别,低等级林麝的皮质醇水平(37.397±1.826 ng·g^-1,n=14)和高等级个体(34.055±2.886ng·g^-1,n=11)间无显著差异(P>0.05)。研究结果表明,圈养林麝雌体的社会等级与其粪样雌二醇水平呈负相关,低等级雌麝的粪样雌二醇水平显著高于高等级雌麝。在麝类驯养实践中,可监测雌麝的社会等级和粪样雌二醇水平变化,预测雌麝的行为健康及繁殖成效。

Relationships between social rank and fecal steroid hormones in captive forest musk deer( Moschus berezovskii)

Social rank of animals has important effects on individuals’resource allocation,community stability and individuals’behavioral strategies.Steroid hormone level of captive animals is correlated with feeding and management,which can reflect the extent of animals’social stress.Understanding the relationships between social rank and steroid hormone level in captive forest musk deer is the precondition and basis of successful ex situ conservation and breeding of musk deer.From June 15thto August 15th,2018,25 forest musk deer (Moschus berezovskii) were sampled and the social rank was calculated by using focus sampling and special event recording methods.The fecal steroid hormone concentration was measured by radioimmunoassay method.The relationships between the social rank of forest musk deer and the concentration of cortisol,testosterone and estradiol in fecal samples were analyzed.The results showed that the estradiol concentration of low rank captive female forest musk deer (289.037±59.710 pg·g^-1,n=11) was significantly higher than that of high rank ones (45.670±27.283 pg·g^-1,n=6)(P<0.05),and the testosterone concentration of low social rank males (3.863±1.538 ng·g^-1,n=3) was not different from that of high rank ones (8.017±1.295 ng·g^-1,n=5)(P>0.05).No significant differences were found in cortisol concentration between low-rank (37.891±7.564 ng·g^-1,n=3) and high-rank males (29.947±2.441 ng·g^-1,n=5),and between low-rank (37.262±1.544ng·g^-1,n=11) and high rank females (37.478±4.628 ng·g^-1,n=6)(P>0.05).Regardless of sex,the cortisol concentration of low-rank forest musk deer (37.397±1.826 ng·g^-1,n=14)was not different from that of high-rank ones (34.055±2.886 ng·g^-1,n=11)(P>0.05).The social rank of female captive musk deer negatively correlated with fecal estradiol level,while the level of estradiol in low-rank females was significantly higher than that in high-rank ones.Social rank and the changes of fecal estradiol level of the musk deer can be monitored to predict the behavioral health and reproductive performance in the farming practices.