School of Natural and Environmental Sciences


Developing lifetime animal welfare assessment tools using novel physiological measures of cumulative chronic stress


The hippocampal formation in the brains of birds and mammals is exquisitely sensitive to both enriching environments and chronic stressors. These two categories of environmental impact have opposite effects in the hippocampus. For example, positive experiences increase hippocampal neurogenesis, while negative ones decrease it. This means that markers derived from the hippocampus are strong candidates for integrative welfare markers which can both detect increases and decreases in animal welfare. In this project, we aim to validate a set of hippocampal markers as welfare indicators in poultry.

The welfare of farm animals is a high-profile public concern, with the goal of ensuring animals have at least a “life worth living” (FAWC, 2009). The intensification of food production, driven by the growth in the world’s population, presents a significant risk to the health and welfare of the animals being used in production. This particularly applies to poultry as the fastest-growing sector of meat production and consumption worldwide. Animal welfare is not just a concern from an ethical point of view. It also has practical health implications. Chronic stress associated with poor welfare can lead to reduced immune system function of livestock and hence an increased likelihood of bacterial food contamination which is a major food security risk. In addition, it also dramatically increases the use by industry of antibiotics to control disease, which increases the chances of antibiotic-resistant pathogens [2].

To meet this challenge, sensitive measures of the welfare of animals in different production systems are needed, both to confirm that products being sold as ‘high welfare’ originate from animals with an actual higher welfare status, and to assess the welfare implications of any new husbandry methods. An ideal welfare measure would be:

In this UFAW-funded project we are taking a novel approach to obtain a sensitive measure of animal welfare by applying neuroscience to develop molecular indicators of welfare status in the brain. Affective state is notoriously difficult to assess in non-human animals, because so much of what we know about affective states comes from introspection, combined with verbal communication. It is therefore not possible to unambiguously measure affective state in any non-human animal. The next best step then, is to measure biomarkers which are strongly associated with different affective states in humans, and make the assumption that this association is more generally applicable than to humans alone.

Through a series of experiments we aim to develop a sensitive measure of animal welfare for chickens and then validate this on commercial farms. Hence the project is of direct benefit to the poultry industry. The neuroscientific approach that we are taking also has implications far wider than poultry alone, and any positive outcomes would facilitate development of similar lifetime welfare assessment tools across all species of farm, companion and laboratory animals.

FAWC (2009). Farm animal welfare in Great Britain: past, present, future. 2009. Farm Animal Welfare Council, UK. p. 1-57.

Blokhuis, H.J., et al. (2008). Animal welfare's impact on the food chain. Trends in Food Science and Technology. 19: p. S79-S87.