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

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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.