While standing tied to the rail, waiting to be tacked up, your horse yawns. Then he yawns again … and then again. By the fourth yawn you start to wonder. Is he tired? Did he swallow a bug? What the heck is going on?
Undoubtedly, some horses yawn because they are tired, just as people and other mammals do. Likewise, contagious yawns have been observed among horses, with one yawner setting off the entire herd. Equine yawns are also thought to be an emotional response, indicating relaxation or submission. Finally, there’s the distinct possibility that yawning equalizes pressure in a horse’s ears, as you may have noticed occasionally happens in your own head.
However, not all of the reasons behind this behavior are benign. Some horses yawn because they are in pain. In addition, repetitive yawning can be a sign of liver disease in both horses and people.
Of course, this doesn’t necessarily mean you need to call your veterinarian if you notice your horse yawn more than usual. Instead, do a quick assessment of his health status. Is he running a temperature? Is he well hydrated and interested in eating? Is he showing any signs of pain or discomfort?
Yawning, when combined with another sign of illness, is cause for a call to your veterinarian. But yawning alone isn’t. Simply keep an eye on the horse and if anything else suspicious develops, reassess the situation.
This article first appeared in EQUUS issue #455, August 2015.