Voluntary participation in behavioural studies offers several scientific, management, and welfare benefits to non-human primates (NHPs). Aside from the scientific benefit of increased understanding of NHP cognition, sociality, and behaviour derived from noninvasive behavioural studies, participation itself has the potential to provide functional simulations of natural behaviours, enrichment opportunities, and increased control over the captive environment, all of which enhance welfare. Despite a developing consensus that voluntary participation offers these welfare enhancements, little research has empirically investigated the ways that participation in behavioural studies may affect welfare. In the current study, we investigated potential relationships between captive chimpanzee welfare and long-term, repeated voluntary participation in noninvasive behavioural studies. We collected behavioural data on 118 chimpanzees at the National Center for Chimpanzee Care (NCCC) in Bastrop, Texas, USA between 2016 and 2018 using 15-minute focal animal samples. Additionally, we collected information on 41 behavioural studies conducted between 2010 and 2018 with the NCCC chimpanzees that involved exposure to a stimulus or manipulation. The total number of behavioural studies in which chimpanzees had participated over the approximately eight-year period was then examined in relation to levels of behavioural diversity, abnormal behaviour, rough scratching, inactivity, and locomotion using a series of regression analyses that controlled for rearing status and age of the chimpanzee at the time of data collection. Analyses revealed significant, positive relationships between the total number of studies in which chimpanzees participated and 1) behavioural diversity scores, R2 adj = .21, F(3,114) = 11.25, p < 0.001; and 2) rough scratching, R2 adj = .11, F(3,114) = 6.01, p = 0.001. The positive relationship between behavioural diversity scores and the total number of studies in which chimpanzees participated seems unsurprising, although we cannot draw conclusions about the directionality of this relationship. The result that rough scratching and the total number of studies in which chimpanzees participated were positively correlated is unexpected. However, rough scratching made up less than 1% of all activity in the current study, and as such, this result may not be biologically meaningful. These findings suggest that participation in behavioural studies is not likely to be detrimental to chimpanzee well-being, and may even be beneficial. Data such as these, which empirically investigate existing recommendations can help inform decisions pertaining to the participation of chimpanzees in behavioural research.

中文翻译：

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圈养黑猩猩（Pan troglodytes）福利与自愿参与行为研究之间的关系

自愿参与行为研究可为非人类灵长类动物 (NHP) 提供多项科学、管理和福利福利。除了从非侵入性行为研究中增加对 NHP 认知、社会性和行为的理解带来的科学益处外，参与本身还有可能提供对自然行为的功能模拟、丰富机会和增加对圈养环境的控制，所有这些都增强了福利。尽管自愿参与提供了这些福利增强的发展共识，但很少有研究对参与行为研究可能影响福利的方式进行实证调查。在当前的研究中，我们调查了圈养黑猩猩福利与长期、反复自愿参与非侵入性行为研究。我们在 2016 年至 2018 年间使用 15 分钟的焦点动物样本在美国德克萨斯州巴斯特罗普的国家黑猩猩护理中心 (NCCC) 收集了 118 只黑猩猩的行为数据。此外，我们收集了 2010 年至 2018 年间对 NCCC 黑猩猩进行的 41 项行为研究的信息，这些研究涉及暴露于刺激或操纵。然后使用一系列控制饲养状态的回归分析，检查黑猩猩在大约八年期间参与的行为研究总数与行为多样性水平、异常行为、粗暴抓挠、不活动和运动的关系以及收集数据时黑猩猩的年龄。分析表明，黑猩猩参与的研究总数与 1) 行为多样性得分之间存在正相关关系，R2 adj = .21，F(3,114) = 11.25，p < 0.001；2) 粗糙划痕，R2 adj = .11，F(3,114) = 6.01，p = 0.001。行为多样性得分与黑猩猩参与的研究总数之间的正相关关系似乎并不令人惊讶，尽管我们无法就这种关系的方向性得出结论。粗略抓挠与黑猩猩参与的研究总数呈正相关的结果出乎意料。然而，在目前的研究中，粗略的抓挠占所有活动的不到 1%，因此，这个结果可能没有生物学意义。这些发现表明，参与行为研究不太可能对黑猩猩的健康有害，甚​​至可能有益。诸如此类对现有建议进行实证调查的数据有助于为有关黑猩猩参与行为研究的决策提供信息。