Horses don't Smile. So - can they be happy?

Professor Natalie Waran OBE

For centuries, scientists debated whether animals experience emotions -whether they had feelings. Most horse owners would probably laugh at this question. One only has to watch horses playing in a field, rolling in the sun, or standing nose to tail grooming each other on a summer's day, and you'd be hard pressed to argue they aren't experiencing emotions that we call contentment, pleasure or even happiness. Fortunately, science is catching up with what horse people instinctively know, and with new research evidence comes improved understanding of the reliable behavioural indicators that horses exhibit when in a positive state of mind, and new possibilities for horse owners to provide for what’s needed for horses to  enjoy a good life.

What Is Happiness?

Happiness is considered a human construct, an immediate emotional experience - a feeling that relies on neurophysiological activation in the brain’s reward system. The reluctance of scientists to study animal emotions including happiness or pleasure probably has its roots in the teachings of early philosophers such as Descartes who believed animals to be like machines, as well as a desire to remain objective, recognising only what can be measured using the scientific method. Emotions seemed too abstract or subjective, just too difficult to measure using traditional scientific methodology. But over the past two decades, this has changed dramatically. Researchers now have more sophisticated tools to investigate not just whether animals have emotions, but what those emotions are, and how they manifest in an animal (ie its physiology and behaviour), and consequently how we can measure/assess them.

This shift has particular relevance for the equestrian world. When the FEI introduced the concept of 'the happy athlete' into dressage judging criteria, it sparked heated debate. Can we really assess happiness in horses? Should it matter for scoring? Some writers controversially asked whether a horse actually needs to be happy to perform a high scoring dressage test. For behavioural scientists with an interest in equine welfare these questions were significant because they suggest that experienced horse people believe emotions such as happiness can be accurately assessed by watching horses whilst they are performing.

We know that with humans, happiness is complex. Psychologists identify several components to the state of happiness: pleasurable activities, good social relationships, feeling engaged in life, and a sense of meaning or purpose. Research shows happiness correlates with both mental wellbeing and physical health (Diener & Chan, 2011).

For horses and other animals, we need to adjust the way we have previously considered emotions. Animal welfare science has traditionally focused on negative states: pain, fear, distress, and discomfort. This made sense from a practical standpoint because stress and suffering seemed easier to identify and measure and related directly to most animal welfare legislation that required animals ‘not to suffer unnecessarily’. But in recent years, researchers have recognised that good welfare isn't just related to the absence or minimisation of suffering or negative emotions such as fear or pain. It also requires evidence of positive experiences (Mellor, 2015), leading to positive emotions that humans term joy, pleasure and happiness.

This raises challenging questions for scientists and equestrians. Do horses experience positive emotions that we call happiness? Can we agree on what these look like? And crucially, can we measure them?

Why Positive Emotions Matter

The importance of positive emotions extends across all farmed and companion animals, with significant implications for productivity, health, and human safety. Research has demonstrated clear links between animal wellbeing and practical outcomes that matter to farmers, animal handlers, and society as a whole.

For example, in dairy cattle, numerous studies show that cows experiencing stress produce less milk and those with positive welfare produce more milk. Cows with access to pasture, comfortable lying areas, and positive human interactions show increased milk yield and quality compared to those in high-stress environments (Hemsworth et al., 2000). The same goes for studies of intensively reared pigs experiencing different types of handling and management – the more space, enriched environments and positive human interactions – the better the animals grow and produce.  The economic implications are substantial: happier cows are more productive cows, laying hens housed in enriched environments with opportunities for natural behaviours produce more eggs with better shell quality than those in barren cages (Lay et al., 2011) and goats provided with positive experiences such as play, social bonding, and environmental enrichment demonstrate improved immune function and reduced disease incidence (Briefer et al., 2015). They also show more cooperative behaviour with handlers, making routine management tasks safer and more efficient.

The practical benefits of promoting positive emotional states in farm animals are significant and  include increased productivity, reduced veterinary costs, improved product quality, better/safer animal-handler relationships, and enhanced public perception of animal agriculture. These benefits make applying the science of animal happiness relevant far beyond academic circles, representing sound economic and ethical practice.

When we consider research related to positive emotion in horses, its less well developed. However, most horse owners can tell when their horse is not feeling well and will point to various indicators such as a ‘dull eye’, lowered head posture, lack of interest in surroundings, and reduced interaction with people. Whilst some of this is related more to experience than science, the development of evidence based tools like the Horse Grimace Scale, now available as an app, has validated facial indicators of pain (Dalla Costa et al., 2014) and made them available to horse owners for use in everyday contexts.

Not surprisingly as with the farm animal narrative, positive equine emotions have proven trickier. When it comes to what we call happiness, comfort, contentment, pleasure, and joy, we're only beginning to develop robust indicators that can be used to reliably assess how the horse is feeling. This research matters because if we can identify what is a positive experience for a horse, what makes him genuinely happy, we can actively promote a good quality of life rather than simply preventing suffering.

Understanding the Emotional Brain

Modern neuroscience provides compelling evidence that like us, animals experience positive and negative emotions. The brain structures and neural mechanisms involved in processing emotions in humans exist in horses and other mammals. Central to this emotional processing is the amygdala, an almond-shaped structure deep within the brain that plays a crucial role in emotional responses, particularly fear and pleasure (Panksepp, 2011).

The amygdala acts as the brain's emotional processing centre, evaluating stimuli for their emotional significance and triggering appropriate responses. In horses, as in humans, the amygdala is involved in forming emotional memories. This means that a horse's past experiences, whether positive or negative, become encoded neurologically and influence future emotional responses. A horse that has experienced gentle, reward-based training will have different amygdala activation patterns, and therefore a different emotional response  when approached by humans compared to a horse with a history of punishment or fear.

Research has also identified the role of neurotransmitters like dopamine and serotonin in reward processing and positive emotional states across species. When horses engage in behaviours they find rewarding, such as mutual grooming or receiving food, these neurotransmitter systems activate, creating the biological basis for what we recognise as pleasure or contentment (Mendl et al., 2010). Classic studies by James Olds and Peter Milner in the 1950s showed that rats would press levers repeatedly to stimulate parts of their brain associated with pleasure, even forgoing food. More recent research has identified 'laughter' in rats during play, detected through ultrasonic vocalisations (Panksepp & Burgdorf, 2003). These findings demonstrate that the capacity for positive emotional experiences is deeply rooted in mammalian neurobiology.

From an evolutionary perspective, positive emotions make sense. When a horse displays relaxation during mutual grooming with a companion, this signals 'keep doing this' and reinforces beneficial social bonds. The immediate positive feeling encourages behaviour that has long-term survival benefits, such as parasite removal and social bonding. Horses learn through reinforcement (both positive and negative- but that’s for another article!), and positive experiences create positive memories that encourage learning through repetition.

Why Emotional State Matters for Human Safety

Not only are emotions important for keeping a horse safe, the emotional state of horses has profound implications for human safety, a concept increasingly recognised under the One Welfare framework, which acknowledges the interconnection between animal welfare  and human wellbeing (and environmental sustainability). Fearful, anxious, or pain-experiencing horses pose significant risks to handlers, riders, and veterinary professionals.

Research into veterinary safety reveals alarming statistics. Studies show that equine veterinarians experience some of the highest injury rates among all veterinary specialities, with many injuries occurring when working with fearful or painful horses (Fritschi et al., 2006). Horses in pain or distress may kick, bite, strike, or flee unexpectedly, creating dangerous situations even for experienced professionals.

Handler and rider safety similarly depends on the horse's emotional state. A comprehensive study of equestrian injuries found that many accidents occur when horses react fearfully or explosively to stimuli (Thompson & von Borstel, 2020). Horses that are chronically stressed, anxious, or in pain are more likely to exhibit unpredictable, reactive behaviours. Conversely, horses maintained in positive emotional states show more predictable behaviour patterns, respond better to training cues, and are less likely to panic in novel situations.

One Welfare recognises that improving horse welfare directly enhances human safety and wellbeing. When horses are kept in environments that promote positive emotional states, with adequate social contact, freedom of movement, and pain/stress-free management, they become safer for humans. This creates a positive feedback loop: calmer horses are easier and safer to handle, leading to better human-horse relationships, which in turn promotes further positive emotional experiences for the horse.

Training methods that prioritise positive emotional experiences also lead to safer horses. Research demonstrates that horses trained using reward-based methods show less fear-related behaviour and greater cooperation compared to those trained with punishment or force (Innes & McBride, 2008). From a practical standpoint, investing in the emotional wellbeing of horses isn't just ethically sound, it's a crucial safety measure that protects those who work with them.

Promoting Positive Emotions: The Three Fs

Whilst research continues to advance our knowledge about emotions, we already know key elements that promote positive welfare in horses and these can be simply summarised as the 3Fs; Friends, Fibre, and Freedom. What we know is that;

Ø  Horses are highly social animals. Recent research shows that horses form strong bonds, preferring certain individuals and showing increased heart rate synchronisation with preferred companions (Krueger et al., 2021). We know from research and experience that isolation and separation represent significant challenges for most horses.

Ø  The equine digestive system evolved for near constant grazing. Research shows that under natural conditions horses will graze for around 16 hours each day. Providing free access to long stem fibre allows horses to engage in natural foraging and feeding behaviour for adequate periods. Research shows that horses on restricted forage budgets show increased stress behaviours and gastric ulceration (Luthersson et al., 2009).

Ø  Horses need access to appropriate space to move freely and express natural and diverse behaviours. Studies demonstrate that horses given paddock turnout show fewer stereotypic behaviours and improved overall welfare compared to permanently stabled horses (Goodwin et al., 2002).

Measuring what matters

Measuring happiness in horses requires researchers to get creative and to borrow from previous research on human emotion. Researchers have so far identified several promising indicators that include:

Ø  Behavioural markers: Play behaviour, affiliative interactions like mutual grooming, and for some species, specific vocalisations appear linked to positive states. Recent work has explored anticipatory behaviour, where horses show increased activity and positive vocalisations before rewarding events (Briefer Freymond et al., 2014).

Ø  Qualitative Behavioural Assessment (QBA): Researchers at Edinburgh and elsewhere have developed systems where observers describe what they perceive an animal to be feeling. When multiple observers show agreement, combined with objective measures like heart rate variability, this provides robust evidence about emotional states (Minero et al., 2009).

Ø  Facial expressions: Multiple research groups have investigated facial markers of emotion in horses. Changes in eye shape, ear position, and blink rate show promise as reliable indicators. Recent studies suggest that eye wrinkles and nostril shape may differ between positive and negative emotional states (Hintze et al., 2016; Merkies et al., 2020).

Ø  Physiological measures: Heart rate variability, a measure of the variation in time between heartbeats, indicates autonomic nervous system state. Higher variability generally suggests a relaxed, positive state (von Borell et al., 2007).

Communicating emotions

Horses communicate their emotional state through body language, posture, vocalisations, and facial expressions. Experienced owners develop expertise in reading their individual horses, but its also important to be open to what research tells us, which may or may not confirm owner beliefs. That quivering top lip during a good scratch, the soft nicker of greeting, the relaxed jaw during grooming are all signals many of us recognise – but we need to be sure that they are reliable indicators of the emotions we believe the horse to be experiencing.

For example, the nicker - a soft, rumbling vocalisation that occurs between familiar horses and between mares and foals is often used by horses who are familiar with their human carers. Whilst often associated with feeding time, many horses nicker specifically for their familiar handlers, initiating contact and soliciting interaction. Research confirms horses can distinguish between familiar and unfamiliar humans and show individual preferences (Sankey et al., 2010).

Scratching and grooming particularly effective areas like the withers can trigger responses similar to those seen during mutual grooming, including lowered heart rate and the characteristic lip movements. These biologically relevant interactions can help establish and maintain positive human-horse relationships (Feh & de Mazières, 1993).

Is there a link between positive emotions and performance?

The link between positive emotions and health appears to be well established in humans. Of course, that’s made easier to assess because we can ask a person! Studies show that people who rate themselves as happiest have cortisol levels significantly lower than those rating themselves less happy (Steptoe & Wardle, 2005). Happy people have better immune function, lower blood pressure, and, it seems, longer lifespans.

This could also apply to horses.  Whilst we can’t ‘ask’ horses and specific research is limited, we know that indirect measures of chronic stress, elevated cortisol, and conflict behaviours correlate with suppressed immune function and increased illness in horses (McBride et al., 2004). Therefore, maintaining horses in positive emotional states likely promotes both  good mental and physical health.

For performance horses, this becomes particularly relevant. A relaxed, content horse will better at manageing the typical stressors associated with the demands of competition life including: transportation, unfamiliar environments, mixing with new horses, training and competition. In addition, a positive emotional state may enhance learning during training and related performance outcomes, whilst also reducing injury risk to humans.

Small things make a big difference

Many equestrian organisations have placed horse welfare at the heart of their strategic plans, and most horse owners share this commitment. However, turning good intentions into practice requires specific, evidence-based actions. The science of equine emotions is starting to provide guidance on what we can do to ensure our horses experience positive welfare.

Firstly, we should provide horses with opportunities to express their natural behaviour. This means maximising turnout (free) time with compatible companions, providing adequate space for movement and play behaviour, and ensuring access to appropriate forage throughout the day. Where full-time pasture living isn't possible, we should aim for the maximum feasible turnout (free exercise) hours and ensure that stabled/stalled or restricted space periods include environmental enrichment and social access.

We must recognise and address negative emotional experiences such as pain and fear promptly and avoid practices that cause these. Given the safety implications of painful/fearful horses for both animals and humans, regular assessment using up to date information and validated tools such as for example, the Horse Grimace Scale should become standard practice. Painful conditions such as those causing lameness, gastric ulcers, dental problems, and musculoskeletal pain all compromise horse welfare. We cannot expect horses to perform or behave reliably when they are experiencing negative emotions.

Training methods must prioritise positive experience and building trust. Research overwhelmingly demonstrates that positive (low stress) evidence based training methods produce better outcomes, not just only in terms of learning efficacy but also in creating emotionally positive associations with humans and worktime. Horses trained through positive training methods are likely to be safer, more reliable, and will arguably experience more enjoyment during their interaction with humans.

In addition investing time in understanding the individual horse,  learning to read the subtle behavioural and facial indicators that reflect emotional state allows us to adjust management and training before small concerns become significant problems. This individualised approach recognises that what promotes positive welfare in one horse may differ for another, depending on their personality, history, and preferences.

Finally, we must all remain committed to continuous learning. The science of animal emotions continues to evolve, providing new insights into what constitutes good welfare. By staying informed about current research and being willing to adapt our practices accordingly, we demonstrate genuine commitment to our horses' wellbeing.

Some References

Briefer, E. F., et al. (2015). Segregation of information about emotional arousal and valence in horse whinnies.

Briefer Freymond, S., et al. (2014). Behaviour of horses in a judgment bias test associated with positive or negative reinforcement. Applied Animal Behaviour Science, 158, 34-45.

Dalla Costa, E., et al. (2014). Development of the Horse Grimace Scale (HGS) as a pain assessment tool in horses undergoing routine castration. PLOS ONE, 9(3), e92281.

Diener, E., & Chan, M. Y. (2011). Happy people live longer: Subjective wellbeing contributes to health and longevity. Applied Psychology: Health and Wellbeing, 3(1), 1-43.

Feh, C., & de Mazières, J. (1993). Grooming at a preferred site reduces heart rate in horses. Animal Behaviour, 46(6), 1191-1194.

Fritschi, L., et al. (2006). Injury in Australian veterinarians. Occupational Medicine, 56(3), 199-203.

Goodwin, D., et al. (2002). The importance of individuality in the assessment of horse welfare. Animal Welfare, 11(1), 127-143.

Hemsworth, P. H., et al. (2000). Relationships between human-animal interactions and productivity of commercial dairy cows. Journal of Animal Science, 78(11), 2821-2831.

Hintze, S., et al. (2016). A framework to assess welfare effects of husbandry interventions and modifications in the keeping of farmed fish. Fish Physiology and Biochemistry, 42(2), 519-529.

Innes, L., & McBride, S. (2008). Negative versus positive reinforcement: An evaluation of training strategies for rehabilitated horses. Applied Animal Behaviour Science, 112(3-4), 357-368.

Krueger, K., et al. (2021). Heart rate variability as a measure of positive emotions in horses. Animals, 11(8), 2439.

Lay, D. C., et al. (2011). Hen welfare in different housing systems. Poultry Science, 90(1), 278-294.

Luthersson, N., et al. (2009). Risk factors associated with equine gastric ulceration syndrome in 201 horses in Denmark. Equine Veterinary Journal, 41(7), 625-630.

McBride, S. D., et al. (2004). Behavioural and physiological responses of horses to different types of horse walker. Applied Animal Behaviour Science, 86(1-2), 109-125.

Mellor, D. J. (2015). Enhancing animal welfare by creating opportunities for positive affective engagement. New Zealand Veterinary Journal, 63(1), 3-8.

Mendl, M., et al. (2010). Cognitive bias as an indicator of animal emotion and welfare: Emerging evidence and underlying mechanisms. Applied Animal Behaviour Science, 118(3-4), 161-181.

Merkies, K., et al. (2020). Preliminary results suggest an influence of psychological and physiological stress in humans on horse heart rate and behaviour. Journal of Veterinary Behavior, 40, 56-63.

Minero, M., et al. (2009). Use of qualitative behaviour assessment as an indicator of welfare in donkeys. Applied Animal Behaviour Science, 121(3-4), 185-190.

Panksepp, J. (2011). Cross-species affective neuroscience decoding of the primal affective experiences of humans and related animals. PLOS ONE, 6(9), e21236.

Panksepp, J., & Burgdorf, J. (2003). 'Laughing' rats and the evolutionary antecedents of human joy? Physiology & Behavior, 79(3), 533-547.

Sankey, C., et al. (2010). Positive interactions with humans may lead to emotionally positive memories in horses. Applied Animal Behaviour Science, 125(1-2), 21-27.

Steptoe, A., & Wardle, J. (2005). Positive affect and biological function in everyday life. Neurobiology of Aging, 26(1), 108-112.

Thompson, K., & von Borstel, U. K. (2020). A review of equestrian sport-related injuries: Mechanisms, risk factors and prevention. Comparative Exercise Physiology, 16(3), 227-234.

von Borell, E., et al. (2007). Heart rate variability as a measure of autonomic regulation of cardiac activity for assessing stress and welfare in farm animals. Physiology & Behavior, 92(3), 293-316.