Welfare assessment of rhesus macaques: from field observation to computational models of brain network

Biologists working with live vertebrates are ethically and legally obliged to optimise the physical and emotional welfare of their subjects, refining husbandry and experimental procedures to minimise the potential for pain, suffering, distress or lasting harm. The welfare of non-human primates involved in neuroscience experiments is of particular concern. Non-human primates perhaps have the greatest potential to experience human-like suffering due to their taxonomic proximity to humans, and neuroscience experiments on non-human primates often last for many years, increasing concerns about potential cumulative effects of experimental and husbandry procedures. Methods currently used to assess non-human primate welfare are inadequate. The goal of this project is to develop new behavioural indicators of primate welfare which are sensitive to the valence of enduring affective states experienced by the animal and which are easy to assess in various settings (academic and industrial settings). We will focus on rhesus macaques, the most common primate species used in neuroscience experiments.

Rhesus macaques live in a highly hierarchical society, with different ranks associated with different levels of chronic stress. The first objective of this project is to assess how an exhaustive list of behaviours varies with hierarchical ranks in a free-ranging population of rhesus macaques in Cayo Santiago (Puerto Rico) to identify potential candidates for behavioural welfare indicators (year 1). The student will then measure the frequency of the pre-screened behaviours in rhesus macaques involved in neuroscience experiments at Newcastle and confirm the valence of the affective state associated with these behaviours using the neuroimaging approach we have recently validated (year 2). To gain further insight into the nature of the affective state associated with macaque behaviours, the student will then compare the brain networks whose structure and activity covary with these behaviours with those involved in several affective disorders in humans (e.g. major depression, post-traumatic stress disorder, bi-polar disorder) (year 3). Finally, the student will investigate which experimental and husbandry procedures might be responsible for the variation in the frequency of different behaviours (year 4).

This studentship will take advantage of our on-going longitudinal database, unique in the world, that combines biannual structural (T1, T2 and DTI) and functional (resting-state) MRI scans of healthy macaque brains, video recordings of home-cage behaviour, blood and hair samples and detailed records of health and exposures to scientific and husbandry procedures. Pre-screening of candidate behavioural indictors of macaque welfare will be done using existing video-recordings of free-ranging macaques living on Cayo Santiago Island, combined with records of their identity, age, sex and hierarchical ranks. In order to put the video collection into perspective, the student will spend two weeks at Cayo Santiago observing social groups of macaques in their natural environment. As such, the studentship will offer a unique opportunity to study primate welfare from field observations to computational models of brain networks.

This project fits the BBSRC strategic priorities 'Welfare of managed animals' and '3Rs in research using animals'. It will allow the PhD student to develop interdisciplinary skills combining animal behaviour and welfare, whole organism in vivo physiology and quantitative skills.