Now, that my mares are on camera, I see them yawning alot everyday and night.
Sometimes have seen one mare yawn the other one and back and forth like us humans
looks like it is contagious, funny to watch.
They are not in pain, colic or ulcers.
Interesting topic.
Did find this information:
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.
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