Analysing horse facial expressions to understand equine emotions and welfare

Reading animal emotions is both an art and a science—especially when it comes to horses. While experienced equestrians have long relied on intuition and experience to gauge a horse’s mood, recent scientific breakthroughs are now offering more objective tools to decode equine emotions. Among these, analysing facial expressions has emerged as a groundbreaking method, shedding light on how horses communicate pain, curiosity, fear, playfulness, and even social bonding.

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في هذه المقالة, we explore how facial expression analysis, particularly through the Equine Facial Action Coding System (EquiFACS), provides valuable insight into horse welfare. We’ll also discuss why understanding subtle cues from a horse’s face is becoming an essential part of equine care in the UK, US, and around the world.

The Science of Horse Facial Expressions

Researchers at the University of Portsmouth in England have developed the first comprehensive anatomically-based ethogram for horse facial expressions. This catalog, published in PeerJ, includes over 800 facial actions across 22 distinct behaviors. These behaviors cover a wide emotional spectrum—from friendly interactions and curiosity to aggression and discomfort. Each facial movement is precisely mapped to the underlying muscle responsible, offering an objective framework to assess emotional state through visual observation.

The scientific model behind this system is called Equine Facial Action Coding System (EquiFACS). It draws on principles from human psychology and primate research, adapted specifically for the unique musculature and behavior patterns of horses. Importantly, EquiFACS enables standardized recording of subtle facial changes such as nostril dilation, eye white exposure, ear rotation, and lip tension—movements that often go unnoticed but speak volumes about the horse’s emotional state.

Why This Matters: Practical Implications for Welfare

There are nearly 60 million horses worldwide, many of which are used in sports, therapy, agriculture, or kept as companion animals. Understanding their emotional state is essential—not just for ethical reasons, but also for effective management and performance.

Misinterpretation of behavior often leads to inappropriate handling or training methods. For instance, a horse showing signs of discomfort may be misunderstood as being stubborn or disobedient. Facial analysis allows handlers, veterinarians, and trainers to separate emotional cues from behavioral noise. This promotes more humane treatment and reduces the risk of injury for both horse and human.

According to Dr. Kate Lewis, one of the lead authors of the EquiFACS study, horses often use the same facial actions in different contexts, but the combinations and intensities vary. This highlights the importance of considering context, not just isolated movements. For example, an open mouth in a playful foal may look similar to an open mouth in a distressed adult horse, but the surrounding muscle actions, ear position, and environmental situation provide critical clues.

Facial Expressions in Different Emotional Contexts

Here are a few examples from the study that demonstrate how different facial combinations correspond to emotional states:

• Playfulness: Depressed lower lips, parted mouths, wide-open eyes, flattened ears, and forward-thrust noses. This expression resembles the open-mouth play faces seen in dogs and primates, suggesting a cross-species evolutionary link.

• Curiosity and Attention: Forward ears, slightly raised eyebrows, and flared nostrils. These expressions help trainers know when the horse is mentally engaged—a useful tool during learning or exposure to new environments.

• Discomfort or Pain: Tightening around the eyes (orbital muscles), tension in the muzzle, and clamped lips. These subtle signs may occur even before more obvious signs like limping or head tossing.

• Aggression or Defense: Backward-rotated ears, tight lips, flared nostrils, and exposure of the eye whites. Recognizing these early can prevent escalation and ensure safe handling.

International Perspectives on Equine Emotion Recognition

In countries like the UK, US, ألمانيا, and the Netherlands, there’s growing interest in animal sentience, and horses are often at the center of these discussions. Welfare organizations and equestrian federations increasingly promote emotion-based assessments of well-being instead of relying solely on physical health indicators like weight or coat shine.

For example, the UK’s RSPCA and World Horse Welfare charities advocate the use of facial pain scales, such as the Horse Grimace Scale (HGS), as part of routine welfare checks. EquiFACS now builds on that foundation, offering a much broader emotional landscape to monitor.

In the US, veterinary schools have begun including facial expression reading in their curricula. Equine-assisted therapy programs also use emotion recognition to ensure horses are not emotionally overstressed—a key concern when horses work with vulnerable humans like children or PTSD sufferers.

Integrating Facial Expression Analysis into Everyday Practice

For horse owners, stable managers, and veterinarians, knowing what to look for is crucial. Here’s how facial expression analysis can be applied in daily life:

1. During Grooming: A horse that flattens its ears or tightens its lips when touched in a certain spot may be signaling pain or discomfort.

2. Before Riding or Training: Observing relaxed facial muscles and forward ears can indicate a horse is ready and willing, while clenched jaws or narrowed eyes might signal anxiety.

3. Post-Surgery or Medical Treatment: Monitoring changes in facial expression can serve as a non-invasive indicator of recovery or emerging complications.

4. In New Environments: Recognizing when a horse is alert but not afraid (e.g., flared nostrils but calm eyes) helps in adapting handling methods to keep them calm and cooperative.

Limitations and Challenges

While promising, this approach is not without limitations. Interpreting facial expressions accurately requires training, experience, and context awareness. Some movements may be breed-specific (e.g., facial muscle variation between Arabians and draft horses), and environmental factors like lighting or dust can obscure facial detail.

Additionally, over-reliance on facial cues without considering full-body language can lead to misinterpretation. For example, tail movement, posture, and vocalizations provide important context that facial expressions alone cannot capture.

Future Directions and Research

With the growth of artificial intelligence and real-time video monitoring, automated facial expression recognition in horses may soon become a reality. Researchers are exploring AI-powered systems that can alert caretakers if a horse exhibits signs of chronic pain or acute distress—even when humans are not around.

Furthermore, EquiFACS is already being expanded into multilingual and multi-breed databases to accommodate differences in horse types and regional handling styles. The goal is to create a universal emotional language for horses, improving welfare standards across borders.

استنتاج

Understanding horse facial expressions is more than a curiosity—it’s a vital step in ensuring their emotional and physical welfare. Tools like EquiFACS provide the means to decode complex emotional states, giving us a deeper connection with these intelligent and sensitive animals.

As our knowledge grows, so does our responsibility. Whether you’re a veterinarian, rider, trainer, or simply a horse lover, learning to read the silent language of equine facial expressions can transform how you care for and interact with horses.

Reference Sources

1. Lewis, K., Wathan, J., & McComb, K. (2024). The Equine Facial Action Coding System (EquiFACS): A scientific method for analyzing horse facial expressions. PeerJ. https://peerj.com/articles/10786

2. RSPCA UK. (2023). Equine Pain and Facial Expression Guidelines. https://www.rspca.org.uk/adviceandwelfare/pets/horses

3. World Horse Welfare. (2024). Understanding horse emotions: Why it matters. https://www.worldhorsewelfare.org

4. University of Portsmouth News. (2023). Scientists decode horse emotions via facial expressions. https://www.port.ac.uk/news-events-and-blogs/news/equifacs-horse-facial-emotions