史密森尼保护生物学研究所物种生存中心 (CSS) 的科学家们正在通过研究异地条件如何影响繁殖来拯救猎豹。

最近，CSS 科学家发现，与住在远离人类的宽敞繁殖中心的雄性相比，将猎豹暴露于传统的公共展览以及三个以上的照顾者会减少精子输出（每次射精的活动精子总数）和整体行为活动。在野生猫科动物中，没有关于雄性数量对群体成员生殖生理或激素指标影响的数据。研究人员考虑了雄性猎豹在异地条件下如何分组（或不分组）的可能性可能会影响射精质量或睾丸激素和糖皮质激素（压力激素）谱。

自由放养的猎豹的社会结构与其他猫科动物大不相同。野生雌性是独居的，只在短暂交配或照顾后代时与其他猎豹在一起。相比之下，男性可以作为单身人士生活，但通常在称为联盟的永久、紧密联系的群体中生活。联盟通常由两到三只动物组成，但最多可以有五只。这些猎豹如何在自然界中存在和生存提供了有关如何管理该物种在异地（圈养）收藏中繁衍生息的线索。

从历史上看，在传统城市动物园管理的猎豹繁殖成功率很低。虽然大多数成年雌性猎豹都是单独饲养的（就像它们生活在野外一样），但其中只有大约 25% 曾经繁殖过。成功繁殖成年雄性的比例甚至更低，约为 18%。目前，大约 85% 的动物园饲养的雄性猎豹以小型联盟的形式进行管理，这是一种吸引人的策略，因为它模仿了野生社会结构，并且动物群体为公众创造了更有趣、更令人兴奋的展品。

该项目探讨了单身与联合管理结构在射精质量和性腺 - 肾上腺激素浓度和概况方面的关系。在给定的猎豹群体中，研究人员还使用行为互动寻找社会等级的证据，然后将行为等级与繁殖指标进行比较。结果可能为群体管理和行为评估的影响提供实用见解，以提高这种稀有且难以繁殖的物种的保护育种效率。

这项研究的结果提供了进一步的证据，表明强加于异地猎豹的生活条件可以深刻影响精液质量。具体而言，CSS 研究人员取得了多项发现，首先是在联盟结构中管理猎豹具有精子输出优势。最多数量的活动精子是由联合雄性产生的，而不是由单身雄性产生的，并且来自同一组内的多个雄性产生了优良的射精。其次，有一些证据表明联盟较高的精子质量值与同时升高的组睾酮浓度之间存在关系。此外，很明显，单身和联合之间的差异不受糖皮质激素下分组的肾上腺激素的调节。尽管雄性猎豹在集中的异地管理下生活在联盟中具有精子输出优势，但更多数量的活动精子不一定是由性腺雄激素或肾上腺糖皮质激素产生的差异或所测量的行为驱动的。

合作者和合作伙伴

物种生存保护中心 (C2S2)
迪克森公园动物园
费城动物园
圣地亚哥野生动物园
白橡树保护
野生动物园
野人
William H. Donner Foundation Inc.
乔治梅森大学

出版物：
科斯特等人 2015a。异地管理的雄性猎豹（Acinonyx jubatus）的活动精子输出受公众暴露和护理人员数量的影响。 PLoS 一 10，e0135847。
科斯特等人。 2015b。群体管理影响雄性猎豹（Acinonyx jubatus）的生殖功能。生殖、生育和发育。
项目人员
Adrienne E. Crosier 博士
David E. Wildt 博士
项目新闻
2018 年 9 月 6 日
七只猎豹幼崽健康成长
2015 年 9 月 30 日
猎豹精子质量
相关动物
猎豹
猎豹

Does Group Management of Male Cheetahs Influence Reproductive Fitness?

Scientists at the Smithsonian Conservation Biology Institute's Center for Species Survival (CSS) are working to save cheetahs by studying how ex situ conditions impact reproduction.

Recently, CSS scientists discovered that exposing cheetahs to traditional public exhibits as well as to more than three caregivers reduces sperm output (the total numbers of motile spermatozoa per ejaculate) and overall behavioral activity compared with males housed in spacious breeding centers away from people. There are no data in wild felids on the influence of number of males on reproductive physiology or hormone metrics of cohort members. Researchers considered the possibility that how male cheetahs were grouped (or not) under ex situ conditions could influence ejaculate quality or testosterone and glucocorticoid (stress hormone) profiles.

Free-ranging cheetahs have a social structure that is mostly different from other felid species. Wild females are solitary, and are with other cheetahs only during brief periods of mating or when caring for offspring. By contrast, males can live as singletons, but often range in permanent, closely bonded groups called coalitions. Coalitions are usually made up of two to three animals, but can have as many as five. How these cheetahs exist and survive in nature provides clues on how the species should be managed to thrive in ex situ (captive) collections.

Historically, cheetahs managed in traditional urban zoos experience poor reproductive success. While most adult female cheetahs are maintained singly (as they would live in the wild), only about 25 percent of these have ever reproduced. The proportion of successfully reproducing adult males is even lower at about 18 percent. Currently, about 85 percent of zoo-held, male cheetahs are managed in small coalitions, an appealing strategy because it mimics wild social structure, and animal groups create more interesting, exciting exhibits for the public.

This project explored the relationships between a singleton versus coalition management structure on ejaculate quality and gonadal–adrenal hormone concentrations and profiles. Within a given cheetah group, researchers also looked for evidence of social hierarchy using behavioral interactions followed by comparing behavioral rank to reproductive metrics. Results may provide practical insights on the influence of group management and behavioral assessments to improve conservation breeding effectiveness for this rare and difficult-to-reproduce species.

The findings from this study provided further evidence that living conditions imposed on cheetahs ex situ can profoundly influence seminal quality. Specifically, CSS researchers made several discoveries, the first that there were sperm output advantages for managing cheetahs in a coalition structure. The highest numbers of motile spermatozoa were produced by coalition males rather than singletons, and multiple males from within the same group produced superior ejaculates. Second, there was some evidence of a relationship between the higher sperm quality values for coalitions and simultaneously elevated group testosterone concentrations. Further, it was clear that the differences between singletons and coalitions were not being regulated by the adrenal hormones grouped under glucocorticoids. Although there were sperm output advantages for male cheetahs to live in a coalition while under intensive, ex situ management, the greater numbers of motile spermatozoa were not necessarily being driven by differences in gonadal androgen or adrenal glucocorticoid production or to the behaviors measured.

Collaborators and Partners

Conservation Centers for Species Survival (C2S2)
Dickerson Park Zoo
The Philadelphia Zoo
San Diego Safari Park
White Oak Conservation
Wildlife Safari
The Wilds
The William H. Donner Foundation Inc.
George Mason University

Publications: 

Koester et al 2015a. Motile sperm output by male cheetahs (Acinonyx jubatus) managed ex situ is influenced by public exposure and number of care-givers. PLoS ONE 10, e0135847.

Koester et al. 2015b. Group management influences reproductive function of the male cheetah (Acinonyx jubatus). Reproduction, Fertility and Development.