Horses are prey animals that evolved to mask pain, making recognition of equine pain a critical but challenging skill for horse owners, handlers, and veterinarians.
Equine pain recognition is complicated by the horse's evolutionary adaptation to mask vulnerability. Horses in significant pain may continue eating, moving, and responding to handlers in ways that lead observers to underestimate their suffering. Trained use of validated pain scales including the Horse Grimace Scale enables more objective assessment. The link between behavioural problems in sport horses and undiagnosed pain is increasingly documented, meaning that horses labelled as difficult or resistant are often communicating pain. Pain assessment training for equine professionals and owners is a high-leverage welfare intervention.