Once, there were the Five Freedoms—looking at what was available to the horse. Then came the Five Domains—looking at the state of the horse itself.
Today, with ever-increasing public scrutiny of animal welfare and a greater understanding of their ethological needs, it’s time for a new welfare-assessment structure that looks at the way the horse views and experiences his life. Animal-centred and based on both physiological and behavioural indicators, the Equine Quality of Life (EQoL) framework is currently under development to meet this new need, by Australian, British, and New Zealander researchers.
“An individual horse’s welfare relies on more than just having food, water, and an appropriate place to live,” said Hayley Randle, PhD, of Charles Sturt University’s School of Animal and Veterinary Science, in Wagga Wagga, New South Wales, Australia.
“The mental health of the horse is now also being investigated, including his or her emotional states and positive and negative (affective) experiences,” she said.
To create a framework for evaluating these states and experiences, Randle and her fellow researchers from the United Kingdom and New Zealand carried out a scientific systematic literature review looking at ‘external’ (behavioural) and ‘internal’ (physiological) ways to assess a horse’s emotions.
The research on external factors was led by Carol Hall, PhD, principal lecturer in equitation science at Nottingham Trent University in the United Kingdom, and reported by Natalie Waran, PhD, equitation science fellow and professor of One Welfare at Eastern Institute of Technology, in Napier, New Zealand. (To read that report click here)
Randle presented the group’s investigation of the internal factors at the 15th annual conference of the International Society for Equitation Science (ISES), held August 19-21 in Guelph, Ontario, Canada.
“There’s a real risk of anthropomorphism when looking at behavioural indicators, so we need sound science on physiological parameters as well to back up what we believe we’re seeing,” Randle said.
Among the 124 peer-reviewed publications they accepted into their review, however, there was a lack of consistency in data and in interpretations of that data with regard to physiological parameters and emotions, she said. For example, the analysis of cortisol – ‘the stress hormone’ – varies widely from one study to the next and takes on different meanings for different research groups depending on the contexts. “Cortisol can be quite confusing,” she said.
Heart rate and heart rate variability can also be confusing, she added, as their readings can be altered for reasons other than emotions, like physical exertion. Their readings are further complicated by the fact that acquiring the data is often a physical challenge. “It’s easy to lose contact with heart rate monitors, for example,” Randle said. “But even if we do just look at heart rate readings, there are conflicting studies about how they relate to behaviour and other measures.”
Another confounding factor—which has so far received little attention—is the possibility that some horses can have poor welfare experiences without showing changes of “emotion” through their cortisol levels or cardiac readings. “Fearful horses may be beyond the state of giving physiological responses, but we don’t know enough about that yet,” she explained.
Additionally, the horse’s life experience will play a role in his overall welfare in ways that could be difficult or impossible to detect through currently used physiological parameters, said Randle.
“While the physiological parameters are important in assessing equine quality of life, it’s clear that they’re limited in this regard,” she said. “Going forward with the new framework, we will need clear, evidence-based parameters, both internal and external in nature, that accurately reflect the way the horse experiences his life, in hopes of ensuring that he is living a good life.”
This work was presented at the 15th International Equitation Science Conference in Canada. You will find a link to download the proceedings here.
To read a report of the related presentation on external quality of life factors, click here.