An animal’s behaviour both causes and reflects changes in its health and welfare. The biological processes underlying these relationships are increasingly well understood in humans. Our group studies such links in animals, in collaboration with colleagues from within the Behaviour and Welfare grouping at Bristol Vet School and other researchers beyond. We investigate how the behavioural biology of animals relates to their health and welfare, and are currently inviting applications in three areas: Subclinical disease in livestock: behavioural markers and affective state Subclinical disease is a big concern on farms as it directly and negatively impacts productivity before any clinical symptoms are detectable. If untreated, it can lead to full-blown symptoms and further disease spread. It therefore has profound implications for food security as well as livestock welfare. While clinical disease is generally characterised by physical signs and a suite of behavioural changes (‘sickness behaviour’), subclinical cases are difficult to detect without blood sampling. Sickness behaviours are caused by clinical levels of pro-inflammatory immune-mediators acting on the CNS. They include conspicuous changes in sleep patterns, reduced food/water intake, mobility, interaction with the environment and group mates, altered cognitive and attention processes, depression-like behaviours incl. anhedonia, and in humans also a self-reported affective state of malaise or feeling unwell. In subclinical cases, levels of the relevant immune-mediators are lower, and their effects attenuated. A key question is whether such effects are still welfare-relevant, and detectable for early treatment. Play behaviour as a health and welfare indicator Play disappears when animals are under fitness challenge, and social play - in rat models at least - is regulated by the subcortical brain areas and opioid neurotransmitter systems that also mediate the hedonic properties of rewards. The suggestion therefore has been that play indicates the absence of fitness threats and is accompanied by pleasure-like subjective states as are experienced during reward consumption. However, play behaviour does not just occur in the absence of fitness challenges, but also in fitness-threatening situations, for example in competitive situations to lower social tension (e.g. canids, some primates). It is also characteristically flexible and variable between and within species, and evidence for opioid involvement is available for one type of play only. Such constraints currently limit the usefulness of play in health and welfare assessment. A better understanding is needed of when play validly and reliably indicates good health and welfare, generalised across a range of species. Social dynamics, health and productivity in free-ranging beef suckler herds Cattle are naturally gregarious, living in cow-calf groups with bulls joining during the mating season. Weaning happens gradually, with heifer calves staying in their native groups while bull calves leave as they reach sexual maturity. We study the social dynamics and associated health and productivity indicators during the natural weaning period and, thereafter, in family groups of free-ranging suckler herds.
PhD or Masters by research: We welcome applications at any time of year from self-funded students with a background in zoology/ biology/veterinary science. Please contact [email protected] if you would like more information.