Many people who deal with horses are aware of the fact, but what is the reason for it? Horses' muscles of the equine lower esophageal sphincter are much stronger than in other animals, making it nearly impossible to open the valve under backward pressure from the stomach. Also, the equine esophagus joins the stomach at a much lower angle than in many animals, so when the stomach is distended, as with gas, it presses against the valve in such a way that holds it even more tightly closed. And, located deep within the rib cage, the equine stomach cannot be readily squeezed by the abdominal muscles. Finally, horses have developed a weak vomiting reflex.

We can only guess why this peculiarity appeared in the process of evolution. Perhaps, keeping food in a stomach was more significant than the need to eject toxins.

Have you known about this fact? Can you suppose why horses have developed such a feature? Please tell us in the comments below!