"Needs," "pleasures," or both? Operationalizing "environmental enrichments" in terms of their impacts on animal welfare and other aspects of biological functioning

我的小组致力于动物福利和贫困住房影响的客观评估，以期以证据为基础改善农场，实验室和动物园的动物福利。这个为期5年的项目致力于“丰富环境”：在贫瘠、无刺激性的笼子里增加复杂性和/或自然行为的机会。它旨在通过提高对环境丰富性对动物功能的许多潜在好处的理解，使环境丰富性的定义和分类正规化。因此，对动物福利科学家来说，成功的丰富可以提高福利——但他们可以通过不同的方式做到这一点（通过仔细结合不同的研究方法，经验主义地梳理出不同的方式）：它们可以通过满足动物对特定资源或活动的需求来减轻慢性压力，或者，也许不那么重要的是，它们可能只是引起积极的情绪或“快乐”。（有些充实甚至可能有两种类型的属性，如果经验导致依赖，就会从“快乐”变成“需要”）。相反，对神经科学家来说，成功的富集会改善大脑结构和功能。这方面有大量的文献；但是，尽管有有趣的证据表明，积极的情绪和/或压力的减轻可能会介导这种影响，但通过改善动物的幸福感来促进动物大脑发育的假设从未得到过验证。其他类型的研究也开始揭示学习的更多长期益处。有些能增强动物的繁殖能力；另一些则允许他们活得更长。减压是一个合理的解释；人类数据甚至表明，快乐（不仅仅是“没有压力”）可以延长寿命。然而，幸福感是否能增强健康，以及它是如何做到这一点的，仍然没有完全解决。通过对水貂和老鼠的一系列集中实验，我们将建立一个关于20多种不同富集物的动机和减压特性的大量数据库，使我们能够统计调查这些效果与（甚至导致）增强大脑发育、繁殖成功率和寿命的关系。这项研究是迄今为止进行的最全面的富集筛选，对评估和改善圈养动物的福利具有相当大的意义。

My group works on the objective assessment of animal welfare & the impact of impoverished housing, with a view to the evidence-based improvement of farm, laboratory & zoo animal well-being. This 5-year program tackles 'environmental enrichment': the adding of complexity &/or opportunities for natural behaviour to barren, unstimulating cages. It aims to formalise how environmental enrichments are defined & categorised, by improving the understanding of their many potential benefits on animals' functioning. Thus to animal welfare scientists, successful enrichments improve welfare - but they can do this in different ways (ways empirically teased apart by carefully combining different research approaches): they may alleviate chronic stress by meet- ing animals' needs for particular resources or activities, or, perhaps less importantly, they may just elicit posit- ive emotions or 'pleasure'. (Some enrichments may even have both types of property, turning from 'Pleasures' into 'Needs' if experience leads to dependency). To neuroscientists, in contrast, successful enrichments cause improvements in brain structure & function. A vast literature exists on this; but despite intriguing evidence that positive emotions and/or stress reduction may mediate such effects, the hypothesis that enrichments enhance animals' brain development by improving their wellbeing has never been tested. Other types of study are start- ing to reveal yet more longterm benefits of enrichment. Some enhance animals' abilities to reproduce; others allow them to live longer. Stress reduction is a plausible explanation; human data even suggest that being happy (not just 'not stressed') improves lifespan. Yet once again, whether wellbeing enhances fitness, & quite how it may do so, is not fully resolved. Through a series of focussed experiments on mink & mice, we will build a substantial database on the motivational & stress-reducing properties of over 20 different enrichments, allowing us to statistically investigate how such effects relate to (even cause) enhanced brain development, reproductive success & lifespan. The most comprehensive screening of enrichments ever conducted, this research has considerable implications for the assessment & improvement of captive animals' welfare.