Investigating the welfare implications of cage size for mink

本项目调查加拿大毛皮养殖场水貂笼子大小对福利的影响，主要调查水貂在有选择时选择的高度和地板面积，以评估欧洲笼子的更高高度和更大地板面积是否比加拿大法规规定的更受欢迎。这个为期三年的项目包括四个实验，如下所示。关于笼子高度的实验1A和B：水貂喜欢什么内部笼子高度，以便从(1A)饲养和在(1B)下进行其他活动？实验2 A和B关于占地面积：加拿大法规和丹麦法律规定的占地面积在以下方面进行了比较：当动物使用这些占地面积饲养动物时，加拿大法规和丹麦法律规定的占地面积如何：水貂应激生理、生长和其他对福利敏感的指标；偏好(即水貂是否自愿选择欧洲笼子提供的占地面积，而不是加拿大笼子提供的占地面积？)；以及群居动物的休息方式，特别是在环境温度较高的情况下(这意味着动物可能希望平躺而不接触，以散热)。这些实验中的每一项都针对最有可能受到楼层面积影响的人生阶段：体温调节可能需要空间分散而不接触的大型双人房男性(2A)和单身成年女性(2B)，因为对他们来说，丹麦和加拿大的楼层面积之差比任何其他生活阶段都大(加拿大的楼层面积不到欧洲楼层面积的60%)。这将产生急需的数据，以向水貂养殖界告知笼子设计的各个方面如何影响他们的动物福利；为下一套国家农场动物护理委员会饲养水貂的护理和处理实务守则(将在2018至2023年期间修订)和全球其他水貂护理指南(例如美国使用的指南)提供信息；以及提供客观数据，说明北美相对于欧洲使用的较小笼子是否对水貂的健康有任何不利影响。这应该有利于这个行业的可持续性，这个行业每年对加拿大的价值约为8亿美元，并有助于改善超过400万加拿大水貂的福利。

This project investigates the welfare implications of cage size for mink on Canadian fur farms, primarily investigating the heights & floor areas that mink elect to use when given a choice, in order to assess whether the greater heights & larger floor areas of European cages are preferred over those stipulated in Canadian Codes. This 3-year project involves four experiments, as follows. Experiments 1A & B on cage height: what internal cage heights do mink prefer, for feeding from (1A) & for performing other activities under (1B)? Experiments 2 A & B on floor space: How do Canadian Codes & Danish legal floor areas compare in terms of: mink stress physiology, growth & other indicators sensitive to welfare, when animals are raised with these floor areas; preference (i.e. do mink voluntarily choose the floor areas offered by European cages over those offered by Canadian?); and how socially-housed animals rest, especially when ambient temperatures are high (meaning animals may want to lie flat out without touching, to lose heat). Each of these experiments is targeted at a stage of life most likely to be affected by floor area: large pair-housed males (2A), who to thermoregulate may need space to lie spread out without touching; and single adult females (2B), since for them the difference between Danish & Canadian floor areas is greater than at any other life stage (Canadian floor areas are less than 60% of European floor areas). This will produce much needed data for informing the mink farming community how aspects of cage design can affect their animals' welfare; for informing the next set of National Farm Animal Care Council Codes of Practice for the Care & Handling of Farmed Mink (to be revised between 2018 and 2023) & other mink care guidelines around the globe, e.g. those used in the USA; and for providing objective data on whether the smaller cages used in North America relative to Europe have any adverse effects on mink well-being. This should benefit the sustainability of an industry annually worth some $800 million to Canada, and help improve the welfare of more than c. 4 million Canadian mink p.a.