Competence to thrive: resilience as an indicator of positive health and positive welfare in animals

A capacity for an animal to maintain or regain healthy functioning in the face of environmental disturbances is recognised as resilience. For the individual animal, dynamic properties of the trajectory of performance traits (e.g. daily milk yield), periodicity of physiological and behavioural variables (e.g. body temperature) and complexity of biological functions (e.g. behavioural repertoire) can provide indicators of its resilience. These indicators provide a view of the individual’s attempts to cope physically (and emotionally) with its non-shared micro-environment. The concept of resilience is examined as a multifaceted attribute that is hidden from direct measurement. The challenges for establishing relationships between general resilience and context-specific resilience such as disease resilience are explored by comparison with the multifaceted construct of temperament (personality). Lower variance in deviations from performance trajectories and stronger periodicity in rhythmic physiological and behavioural variables are mostly heritable and favourably associated with health and longevity. In humans, wellbeing is associated with health outcomes, and biomarkers of health are more strongly associated with eudaimonic than hedonic wellbeing. The psychological state of eudaimonia is associated with the capacity to express agency, function well, fulfill biological potential and express environmental mastery. The need for indicators of eudaimonia in animals has been suggested previously. Links between environmental mastery and the capacity to develop and express physiological, immune, behavioural, cognitive and affective competencies are examined. It is suggested that longitudinal data on individual animals can provide a precision physical indicator of eudaimonic positive welfare. In this view, positive welfare entails both eudaimonic and hedonic aspects of wellbeing, neither of which is alone sufficient to describe or to maximise positive welfare. Cumulative scores of resilience may have utility for assessing the lifetime welfare experience of the individual and when summed at the farm level may provide a metric for benchmarking welfare performance. Breeding for resilience selects for normativity of biological functions assessed against the individual animal’s own baseline of inherited and developmentally acquired potential. This differs from current approaches to selection for production, which aim to maximise production or production efficiency benchmarked against the group mean. Biological costs and trade-offs for resilience require further research.