When a horse is injured, recovering from surgery, struggling with arthritis or facing a lengthy hospital stay, most veterinary assessments focus on what can be measured physically. That means pain, lameness, wound healing, body condition or other clinical signs. But what about the horse’s mental state?

Alessia Masini is an MSc. candidate at the Ontario Veterinary College under the supervision of Christopher Riley BSc (Physics), BVSc (Hons), MSc. PhD, Diplomate ACVS, PGCIM, MANZCVS, CertTeReo, ARTech I. She aims to better understand how equine veterinarians perceive the effects of illness and injury on a horse’s mental state. 

Through an international survey launched in August, Masini and the research team hope to capture the expertise of equine veterinary professionals and further evolve conversations in equine welfare science. The anonymous online survey asks veterinarians, among other questions, to assign behavioral descriptors to a range of clinical scenarios. By starting this conversation, the project creates an opportunity for meaningful collaboration between animal welfare scientists and veterinarians. These people play a critical role in advocating for horse welfare and supporting the equine industry’s social license to operate.

Five Domains model

Riley explains, “Vets can articulate that a horse is depressed, unhappy or in pain. But the survey invites deeper contemplation of other descriptors more commonly cited in animal welfare research. One goal is to better understand veterinary perceptions of how illness and injury may affect a horse’s mental state and have vets further deliberate that connection.”

For many horse owners, conversations about welfare begin with the three F’s (Friends, Forage and Freedom) or the Five Freedoms. These focus on protecting animals from hunger, discomfort, pain, fear and restrictions on normal behavior. 

Just over two decades ago, the Five Domains Model was developed. This built on the Five Freedoms by recognizing that welfare is ultimately reflected in an animal’s mental state and the balance of positive and negative mental experiences. The model considers four physical and environmental domains (nutrition, environment, health and behavioral interactions) and how they collectively influence the fifth domain: mental state.

Translating model into ‘practical tools’

While the Five Domains Model has gained acceptance in animal welfare science, translating it into “practical tools” for equine clinical practice remains a challenge. Welfare assessments in veterinary settings often focus on physical health. This leaves questions about the horse’s mental experience less clearly defined. As the chair of Clinical Studies at the Ontario Veterinary College and past Deputy Chair of the National Animal Welfare Emergency Management Committee of the New Zealand Government, Riley explains, “There’s not really a systematic way in which we consider the welfare of the horse that is aligned with the five domains in everyday practice. A long-term goal would be development of a way for veterinarians to frame other aspects of welfare during their consults that extend beyond physical assessment.” 

With their study firmly based on the five domains model, Masini emphasizes the need for a strong link between physical and mental states. She is interested in the preliminary information from veterinary professionals on how they perceive illness or injury to affect mental state. “Veterinarians see how horses behave between regular visits and how their behavior progress and changes,” she explains, illustrating the value this feedback will provide.

One of the survey questions will establish whether the veterinarian is familiar with the Five Domains model. There is anticipation of a variety of answers depending on whether the practitioner has graduated recently or has been practicing veterinary medicine for a number of years. Geography may be another factor. For example, greater familiarity is expected in New Zealand (where the Five Domains model was developed), Australia and the U.K. 

Increasing importance

Riley and Masini underscore that understanding how veterinarians assess a horse’s mental state will become increasingly important as the Five Domains Model is progressively dopted within animal welfare codes of practice and emerging legislative frameworks around the world.

Masini continues, “The challenge is that veterinarians need assessment tools that are practical, scientifically validated and feasible to use in busy clinical settings. This research survey is a first step toward understanding how that might be achieved.”

Riley brings up the Equine Facial Grimace scale as an example of a practical, scientifically-validated welfare assessment tool currently in use. He says many equine hospitals post pictures for easy reference. Understanding micro-expressions can prove very useful in identifying anxiety and pain in a horse.

Power of interventions

Also lead author and senior editor of  Fraser’s The Behaviour and Welfare of the Horse | CABI Books, Riley describes opportunities for intervention to lower anxiety in horses in stressful situations like hospital stays. “Interventions that take as little as three to five minutes can make a huge difference, increasing comfort level and cooperation,” he says. 

Examples include introducing a cardboard cut-out of a foal if a mare becomes stressed when separated from her foal. The use of mirrors can also help. Another option is conducting a simple behavior modification exercise before administering a needle. (Equine behaviorist Gemma Pearson demonstrates this in the “Don’t Break Your Vet” video series on YouTube.) Anything that helps reduce anxiety before it escalates contributes to a safer environment for horse, handler and practitioner.

The findings from this survey may help identify common behavioral descriptors associated with different health conditions and levels of stress. This could provide a foundation for future research and the possible development of practical welfare assessment tools for veterinarians.

Better owner understanding

Masini believes the work may also help horse owners better understand what their horses may be experiencing when dealing with illness or injury.

“Behavioral changes are often one of the first signs that something is wrong,” says Masini. “We hope this research also encourages owners to pay close attention to changes in their horse’s behavior and seek early intervention when needed. It may also help people interpret behaviours differently. For example, aggression may be recognized as a potential indicator of pain rather than dismissed as a horse being ‘naughty.’ The flip side would be noticing discomfort in a horse appearing unusually quiet or unresponsive rather than believing them to be well-behaved and very cooperative.”

Should the survey reveal consistent patterns in how veterinarians describe and assess horses across a range of clinical conditions, the researchers see opportunities for further study. This might include the development of standardized behavioral descriptors and more comprehensive welfare assessment frameworks for hospitalized horses.

Encouraging discussion

Raising awareness of the Five Domains Model will be another benefit of the survey, concludes Riley. “Anything that encourages discussion about welfare is a positive outcome. This project creates an opportunity for veterinarians and animal welfare scientists to come together, share perspectives and advance our understanding of the horse’s experience during illness and injury.”

The Canadian Veterinary Medical Association, the American Association of Equine Practitioners (AAEP), the British Equine Veterinary Association (BEVA) and other veterinary networks are distributing the survey globally. It will remain open for participation until December 2026.

Horse owners can support the project by spreading the word and encouraging their veterinary professionals to participate. This 10–15 minute anonymous survey is titled ‘Veterinary perceptions of the effects of illness and injury on the mental state of the horse.’ It will remain open until the end of December, 2026. Every response will contribute to a better understanding of how illness and injury may affect a horse’s mental state. It will also help inform future approaches to equine welfare assessment.

Landing page image by iStock