Captive breeding is vital for primate conservation, with modern zoos serving a crucial role in breeding populations of threatened species and educating the general public. However, captive populations can experience welfare issues that may also undermine their reproductive success. To enhance the wellbeing of endangered zoo primates, we conducted a study to assess the effects of a new scent enrichment program on captive red‐ruffed lemurs (Varecia rubra), black howler monkeys (Alouatta caraya), siamangs (Symphalangus syndactylus), lar gibbons (Hylobates lar) and orangutans (Pongo pygmaeus pygmaeus). We combined behavioral observations and fecal endocrinology analyses to evaluate the effects of a series of essential oils (benzoin, lavender, lemongrass) on five captive troops (N = 19) housed at Dudley Zoo & Castle and Twycross Zoo (UK). We recorded observations of natural species‐specific and abnormal stress‐related behaviors for 480 h using instantaneous scan sampling. We collected 189 fecal samples and measured the fecal cortisol concentrations using radioimmunoassay. We found a significant effect of the scent enrichment on behaviors, with red‐ruffed lemurs and black howler monkeys reducing their social interactions, as well as red‐ruffed lemurs and lar gibbons decreasing their stress‐related behaviors after they were exposed to the series of essential oils. We also found that red‐ruffed lemurs displayed a significant increase in fecal glucocorticoids following exposure to essential oils. Our contradictory findings suggest that the effects of this series of essential oils may change depending on the species‐specific social lives and olfactory repertoires of primates. In conclusion, we cannot recommend using these essential oils widely with zoo primates without additional evaluation.

中文翻译：

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气味浓缩对动物园灵长类动物应激行为和生理指标的影响

圈养繁殖对于灵长类动物保护至关重要，现代动物园在繁殖受威胁物种和教育公众方面发挥着至关重要的作用。然而，圈养种群可能会遇到福利问题，这也可能会影响其繁殖成功。为了提高濒临灭绝的动物园灵长类动物的福祉，我们进行了一项研究，以评估一种新的气味强化计划对圈养红颈狐猴 ( Varecia rubra )、黑吼猴 ( Alouatta caraya )、暹罗猴( Symphalangus syndactylus )、长臂猿的影响( Hylobates lar ) 和猩猩 ( Pongo pygmaeus pygmaeus）。我们结合行为观察和粪便内分泌学分析来评估一系列精油（安息香、薰衣草、柠檬草）对五名俘虏（N = 19) 安置在达德利动物园和城堡和特威克罗斯动物园（英国）。我们使用瞬时扫描采样记录了 480 小时的自然物种特异性和异常压力相关行为的观察结果。我们收集了 189 份粪便样本，并使用放射免疫测定法测量了粪便皮质醇浓度。我们发现气味丰富对行为有显着影响，红颈狐猴和黑吼猴减少了它们的社交互动，以及红颈狐猴和长臂猿在暴露于一系列的压力相关行为后减少了它们的压力相关行为。精油。我们还发现，红颈狐猴在接触精油后粪便中的糖皮质激素显着增加。我们相互矛盾的发现表明，这一系列精油的作用可能会根据灵长类动物的物种特定社会生活和嗅觉功能而改变。总之，我们不建议在没有额外评估的情况下将这些精油广泛用于动物园灵长类动物。