A reliable way to objectively assess the mental state of horses continues to elude scientists, Professor Natalie Waran told delegates at the recent annual conference of the International Society for Equitation Science (ISES).
This was despite recent research into behavioural indicators of negative moods in animals, she told a plenary session at the gathering in Wagga Wagga, Australia.
Waran, from New Zealand’s Eastern Institute of Technology, said physiological measures such as heart rates, although potentially able to provide objective evidence, reflected arousal rather than emotional valence.
There was, she said, no physiological measure that distinguished between positive and negative emotions in the horse. And behavioural signs did not always reflect physiological responses.
Waran noted that cognitive bias studies had been used in several species to determine a ‘positive’ or ‘negative’ outlook, but they had yet to be used successfully in horses.
Waran, a co-founder of ISES, said successfully identifying validated indicators of negative and positive emotions in the horse was critical, as they could then be used to determine how different situations and experiences affected horses.
The conference’s central theme this year was equitation science in practice, exploring collaboration, communication and change.
Until recently, equine welfare research explored the effects of negative welfare by measuring physical parameters related to stress, such as cortisol, heart rate, heart-rate variability and eye temperature.
It was now more commonly recognised that the absence of pain and/or stress was not enough and, if scientists and owners are to consider the whole horse picture, they must also measure the presence of positive experiences.
Waran discussed the merits of a developing an Equine Quality of Life (EQoL) assessment tool – essentially a toolkit of measures which considers the balance of positive and negative emotions from the horses’ point of view.
She described the challenges of appraising both the measurable and the immeasurable elements of what it meant to be a “happy horse”.
Waran challenged delegates to consider how best to assess the expression of emotion in horses, given that, in trials, the measurable physiological indicators of stress, such as cortisol and heart rate, can be quite independent of outward behavioural changes. These measures were useful, she said, but by no means exhaustive, when considering emotion.
Behavioural changes can be an indirect measure of negative emotion; for example, noticing a withdrawal of engagement with the environment or, for a familiar horse, simply noticing that something is “not right”.
Studies that offered horses choice over their environment may indicate that improved welfare might be gained from giving horses more control over their care and living arrangements. This testing method is already used in production animal industries, for the likes of testing the choices caged hens make and the strength of their motivation for certain resources such as perches.
However, given that horses, as prey animals, have a species-specific tendency to mask their underlying negative emotional state as a means of survival, this made the behavioural assessment of compromised emotional states especially challenging.
Waran said that whilst there were recognised behavioural indicators of pleasure, and it is clear that horses will display an active preference for something they find pleasurable – for example, a scratch in just the right spot – these apparent preferences needed to be carefully assessed.
There may be a number of reasons why a horse behaved as it did, she said.
Waran concluded by urging delegates to “be the change” they would like to see.
To thoroughly understand what good welfare meant, they must step beyond the limitations of the available scientific methodologies and test the assumptions made about horses, by attempting to see the world from the horse’s point of view.
Waran describes her research and education interests as being in the field of ‘One Welfare’ – the relationship between animal and human health and welfare, an interdisciplinary area combining aspects of social sciences, health and veterinary sciences with education, ethics and law.
She has a long-standing research and practical interest in horse behaviour and welfare, having published on several topics including horse transport, welfare assessment, temperament testing, weaning, feeding and stereotypies, indicators of stress and pain behaviours.
The conference drew 170 delegates from 17 countries.
The conference proceedings can be read here.