Validating reward-related behaviour for welfare assessment, and improving welfare through increased predictability of events

我们有很多方法可以衡量圈养动物的福利。这些指标包括生物功能（如健康、长寿）、动物是否表现出它们所适应的自然行为，以及动物的感受（情绪状态，如快乐或恐惧）。我们需要新的、实用的方法来评估动物的情绪状态，并根据这些福利措施来确定它们的价值。在空间和财政限制的情况下，还需要设法改善实验室饲养和用于研究和测试的动物的福利。该项目的第一个目标是验证一种测量实验室饲养的猕猴和狗的情绪状态的新方法，这些猴子和狗被用于实验室研究和测试，内政部对此有特别的理由。有充分的证据表明，动物对宣布的奖励有多敏感，这可以通过它们知道奖励即将到来时的预期行为来衡量，这反映了潜在的福利状态。例如，如果动物生活在一个丰富的环境中，有机会表现出自然的行为，并与同伴进行积极的社会接触，那么可以预测，它对积极的奖励不会那么兴奋，因为它的生活中已经有了许多积极的因素。生活在不那么丰富的圈地里的动物，积极的经历更少，甚至还有一些消极的经历，被预测会更容易被宣布的积极奖励所激发，并且对它更敏感。奖励敏感性在衡量福利状态方面的有用性将在实验室中对集体饲养的动物进行测量，并将结果与工业中常规收集的其他福利指标进行比较。这项研究的第二个目的是通过告知实验动物将要发生的事情来改善它们的福利。有相当多的证据表明，动物更愿意知道事件何时发生——无论这些事件是积极的还是消极的。我们可以通过引入与特定类型的事件相关的独特而可靠的信号，并在该事件发生之前始终使用该特定信号，来告知动物事件何时发生，以及它们的性质是什么。例如，一种特定的声音可能会告诉动物笼子将要被清理，另一种声音是它们要被抓起来称重，另一种声音是食物要来了。这些独特可靠的信号让动物们为事件做准备，在没有信号的情况下，它们也能放松下来，因为它们知道自己是“安全的”。相反，如果一个积极的事件被发出信号，动物可以体验到期待这个事件的愉悦状态（想象一只兴奋的狗，当它知道它要出去散步时）。采用不同动物组的实验设计，接收到积极的信号事件，消极的信号事件，以及这些信号的组合，该研究将记录在工业中收集的行为和其他福利相关措施（如心率），以确定引入信号的效果。如果这种简单的方法不需要人员培训或时间投资，并且可以在不改变实验室基础设施的情况下引入，具有明显的福利效益，那么它可以推广到实验室使用的所有动物，以及其他圈养环境。

There are many ways we can measure the welfare of animals in captivity. These include measures of biological functioning (such as health, longevity), whether the animals are expressing natural behaviours which they are adapted to perform, and how animals are feeling (emotional state, such as happy or fearful). New and practical methods of assessing the emotional state of animals are needed, and their value determined in relation to these other welfare measures. Ways to improve the welfare of animals housed in laboratories and used for research and testing are also required, within space and financial limitations.The first aim of this project is to validate a new way to measure emotional state in laboratory-housed macaque monkeys and dogs, which are, with special justification to the Home Office, used in laboratory research and testing. There is good evidence that how sensitive an animal is to an announced reward, which can be measured in their anticipatory behaviour when they know the reward is coming, reflects underlying welfare state. For example, if the animal is living in an enriched environment, with opportunities to perform natural behaviours and with positive social contact with companions, it is predicted that it will be less excited about a positive reward because it already has many positive elements with its life. An animal that is living in a less enriched enclosure, with fewer positive and indeed some negative experiences, is predicted to be more aroused by an announced positive reward, and have increased sensitivity to it. The usefulness of reward sensitivity in measuring welfare state will be measured in group-housed animals in the laboratory, and the findings compared with other welfare measures collected routinely in industry.The second aim of the research it to improve the welfare of laboratory animals by informing them of what is going to happen to them. There is considerable evidence that shows that animals prefer to know when events will occur - whether these events are positive or negative. We can inform animals when the events will occur, and what their nature is, by introducing a unique and reliable signal associated with a specific type of event, and always preceding that event with this specific signal. For example, a specific auditory tone might inform the animals that cage cleaning will occur, a different tone that they are to be captured for weighing, and another tone that food will arrive. These unique reliable signals allow the animals to prepare for the event, and in the absence of signals, they are also able to relax as they know they are "safe". Conversely, if a positive event is signalled the animal can experience the pleasurable state of anticipating this event (think of an excited dog when it knows it is going to go out for a walk). Using an experimental design with different groups of animals that received signalled positive events, signalled negative events, and a combination of these signals, the study will record the behaviour and other welfare-related measures collected in industry (such as heart rate) to determine the effects of the introduction of signals. If this simple method that does not require staff training, or time investment and can be introduced without changes to laboratory infrastructure, has clear welfare benefits, then it could be rolled out for all animals used in laboratories, and in other captive settings as well.