Why Do Horses Yawn?
When horses yawn, it is not necessarily for the same reason we humans do. It could be a sign of discomfort.
March 14, 2017
What makes a horse form his mouth like he is yawning? Is he really yawning or is it something else?
The American Association of Equine Practitioners helped us with the answer.
Unfortunately, there is no simple answer that explains why a horse yawns. There are some veterinary medical professionals who firmly believe that the behavior we attribute to yawning in the horse is actually a manifestation of pain or discomfort. Some believe that so strongly that they propose that a horse only yawns when he is uncomfortable.
Certainly, many horses will yawn when experiencing colic pain, but no one knows precisely why the horse responds this way or what the yawn might do to make him feel better.
Horses also might yawn if they have oral pain, and some horses yawn just after removing the bridle, presumably to stretch jaw muscles. At one time, many hypothesized that the horse might be trying to equalize pressure inside the inner ear, much like humans often do when driving in the mountains or riding in airplanes. This has not been proven.
We have all seen our horses yawning while seemingly happy and quiet in their stalls or pens. And sometimes horses will yawn close to meal times, as if they are anxiously anticipating their hay or grain. With so many seemingly contradicting triggers, it is very hard to imagine a single cause for yawning.
About the only thing we're fairly sure of is that the trigger is not the same as that of a yawn in humans, which is in response to transient drops in blood oxygen levels. That big intake of fresh air increases oxygen in the lungs and therefore in the vascular system. However, horses do not appear to be inhaling when they yawn.
The most important thing to keep in mind if your horse seems to be yawning inappropriately is that it can often be a sign of abdominal pain. Take quick stock of the situation and make sure there are no other signs of colic. If you have doubts, observe your horse closely for a few minutes, and if you still have questions, call your veterinarian. Most times when your horse yawns, however, he is likely to be just fine and doing what horses do.
--From the American Association of Equine Practitioners
*AQHA and the provider of this information are not liable for the inherent risks of equine activities. We always recommend consulting a qualified veterinarian and/or an AQHA Professional Horseman.