Metabolism cages are designed to conduct absorption, distribution, metabolism and excretion (ADME) studies, enabling an 'excretion balance' scientific objective to be met. Historically, the design of dog metabolism cages has involved single housing. This type of housing has limitations for normal social behaviours and has been largely unchanged for 25-30 years. Improving animal welfare is a focus area for the authorities as well as the industry throughout the European Union. A collaboration was developed between Novo Nordisk and Covance to enhance the design of metabolism cages, allowing dogs to be pair housed. The purpose of the study was to compare excretion balance data from pair-housed and singly housed dogs in order to demonstrate that conducting excretion balance studies with a pair-housing design improves animal welfare without compromising the scientific integrity of the study. A radiolabelled test compound, [14C]-Quetiapine, was selected for this investigation based on its excretion profile. The assessment of the dogs' stress levels was investigated by measuring the levels of serum cortisol as an indicative biomarker. Results were inconclusive due to large variations in cortisol levels. However, dogs appeared calmer in the pair-housing setting. The overall mean recovery (±standard deviation) for pair-housed animals (94.0 ± 0.66% of the dose) was equivalent to that from singly housed dogs (93.0 ± 2.29%). Based on these data, we conclude that pair housing of dogs for future metabolism ADME studies does not compromise the scientific integrity, and therefore is a major progression in the design of these studies, enhancing welfare.

中文翻译：

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一种进行犬新陈代谢研究的新颖的福利和科学方法，可将犬配对饲养。

代谢笼设计用于进行吸收，分布，代谢和排泄（ADME）研究，从而实现“排泄平衡”的科学目标。从历史上看，狗的新陈代谢笼子的设计只涉及单一的住房。这种住房对正常的社会行为有局限性，并且在25到30年中基本上没有变化。改善动物福利是欧盟当局以及整个欧盟行业的重点领域。诺和诺德（Novo Nordisk）和Covance之间进行了合作，以增强新陈代谢笼的设计，使狗可以成对饲养。这项研究的目的是比较成对饲养和成年饲养的狗的排泄平衡数据，以证明进行成对居住设计的排泄平衡研究可以改善动物福利，同时又不影响研究的科学完整性。根据其排泄曲线，选择了放射性标记的测试化合物[14C]-喹硫平进行此项研究。通过测量血清皮质醇水平作为指示性生物标志物来研究对狗的应激水平的评估。由于皮质醇水平的巨大差异，结果尚无定论。但是，在成对安置的环境中，狗显得比较平静。配对动物（剂量的94.0±0.66％）的总体平均回收率（±标准偏差）与单只狗的总体平均回收率（93.0±2.29％）相同。根据这些数据，