When observing signs of stress, the first step should be to rule out pain. We cannot expect a horse in pain to be in peak performance; it is simply unfair and sets the horse up to fail. In order to be successful in training, we must set the horse up for success, and that starts with a clean bill of health before placing a workload on the animal. Horse owners generally understand that horses can feel pain, but often, they do not recognize signs of pain that their horses are exhibiting (1, 2). To be safe, it is best to call the vet when new stress behaviors are observed and keep the horse on a regular farrier cycle. It is also important for your vet and farrier to work together to address lameness.
Many causes of pain can be internal or need veterinary intervention. While certain conditions, like a pulled muscle, may be easily treated on your own, other conditions, like a ruptured tendon, need professional care to make sure it is properly treated and monitored. Monitoring for signs of pain in daily health checks will help to catch issues early, so you can address it before it gets worse. Beyond the musculoskeletal system, a horse can experience pain or distress from a condition elsewhere in the body, such as neurological (brain), cardiovascular (heart), or gastrointestinal (gut) (3-12). Through various imaging and tests, vets can either find the source of the pain, or rule out medical conditions as the source of the behavior.
Note: There are times in which the condition can only be diagnosed after euthanasia during a necropsy. This is often considered behavioral euthanasia due to the behaviors escalating to the point of being unsafe to handle, but the undiagnosed medical condition was still the cause of the behaviors.
AAEP Lameness Scale
In the video, you will see one of the many ways that a vet can diagnose pain in your horse. For an x-ray due to lameness, the vet would likely perform a lameness exam, including a flexion test. Using the AAEP scale for lameness (above), you can determine the degree of lameness prior to calling the vet. Mild lameness (Grade 2) might not warrant a call, but persistent mild lameness does. Knowing the signs of pain beyond their gait can indicate how much pain the horse might be experiencing. We can typically see additional signs of pain through the Posture and Facial Expression (13-18).
Lameness may also indicate an issue with the horse's feet. Just like our fingernails, a horse's hooves will grow continuously over the horse's lifetime, and the health of the hoof is dependent on many factors like nutrition, ground moisture (mud/puddles), and more (19, 20). In natural conditions, horses do not need the same hoof care that domestic horses do because they walk miles every day searching for food over rocky ground (21). Domestic horses are often restricted in their movement either in stalls or small paddocks, preventing them from covering that same distance. The diet we provide can also play a role in causing hoof issues, especially since we misunderstood their dietary needs for so long! High sugar pellets have been seen as a major cause for laminitis in horses (23). Keeping horses on a regular farrier schedule will prevent overgrowth in the hoof, and promote healthy hoof angles for correct movement. To suit a horse's individual needs, the farrier might recommend anywhere between 4-8 week cycles.
Lack of farrier care can result in (19, 20, 22):
Hoof overgrowth
Unhealthy hoof and leg angles
Infection
Thrush
Abscess
White Line Disease
And More
All of these conditions can cause pain and discomfort, which affects their Posture, Facial Expression, and Gait.
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