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

Animal welfare can be measured on a scale of poor to good, and will at any one point reflect the balance of their positive and negative affective states. Behaviour is the most accessible measure of welfare, being the result of all the animal's own individual decision making processes and also expressing their emotions. By measuring anticipatory behaviour to announced rewards, we can determine an animal's reward sensitivity, which reflects the brain's evaluation of its subjective state and the environment. Behavioural activation in anticipation of a reward involves mesolimbic dopaminergic systems; these systems are known to be sensitized by stressors suggesting the biological mechanism underlying the use of such behaviour in welfare assessment. The animal is adapted to select the most efficient (i.e. most rewarding) response, and those with more stress will show higher levels of anticipatory behaviours for a reward, whilst those with positive experiences with have less anticipatory behaviour. The first goal is to validate this measure, with a battery of other welfare measures in macaques and dogs in a working laboratory environment, to show practicality. The second goal is to manipulate signalled predictability to inform laboratory animals of what will happen to them. Evidence strongly suggests that animals prefer predictable events, be they positive (e.g. appetitive) or negative. Knowing, through a reliable signal which can be classically conditioned over paired trials, when events will happen is good for welfare (the preparatory hypothesis), and also informs animals when they are safe (the safety signal hypothesis). The project will systematically investigate and validate this new welfare assessment tool, and assess an associated Refinement that is cost effective, requires no changes to the physical infrastructure, and can be implemented widely to improve welfare and reduce the adverse impact of procedures, with potential to improve the quality of scientific output.

• Resources: Refining dog care
• News: How home pen design affects the welfare of laboratory dogs
• Awards and Prizes: NC3Rs 3Rs Prize, February 2016
• Blog: Improving the welfare of laboratory dogs
• Further Funding: NC3Rs PhD Studentship, Refinement of rearing practices in marmosets, February 2011, £120,000