Whenever possible, horses should be fed from the ground, and this includes concentrated feed and hay.
We have heard that studies indicate horses actually create FAR more saliva when they eat in this natural position compared to elevated feeding, and this helps prevent choke and likely aids in digestion (this less risk of colic and ulcers). A study reportedly found horses chew more times, as well.
Particles cause fewer respiratory issues in a natural position.
In our experience, horses certainly do choke less and have fewer breathing issues.
Studies indicate even in trailering and so forth, horses have increased risks when their head is tied / kept up.
“Under natural conditions, horses spend about 60 to 80 percent of their time with their heads down, grazing. When fed hay at ground level, the horse spends a lot of time with his head down–though it takes less eating time for hay than grazing at pasture. The heads-down position is healthiest for the respiratory tract, which relies on gravity and downward drainage to help clear out any foreign particles and respiratory secretions–draining them out through the lowered nose.
Respiratory irritations from foreign particles produce extra fluid secretions to help flush them out. These must drain out the nose or be coughed out–which the horse does with his head down to facilitate expulsion. The lining of the windpipe contains hair-like cilia that constantly move in one direction, to push foreign particles like dust and bacteria toward the nose and throat, and this works best in conjunction with gravity, with the head down.
An Australian study in 1992 showed that horses forced to keep their heads up are more at risk for respiratory infections, including bacterial lung infections. The Australian researchers found that in 21 out of 24 mares who spent 24 to 48 hours with their heads tied up, there were more white blood cells (neutrophils, which respond to infections) and more bacteria in the lungs, than in horses who did not have their heads tied up. Eight of the heads-tied-up mares developed mild coughs after the 48-hour period, and three others were obviously ill with respiratory infections. After the mares were allowed freedom of head and neck so they could lower their heads for drainage and cough more effectively, all recovered.
Whenever possible, horses should be allowed enough freedom of the head to eat in a low position. Horses shipped or hauled, or living in straight stalls with feed and water at or above shoulder level, are more at risk for lung problems. A horse in a straight stall should be tied long enough so he can lower his head, and fed from a low manger or feed box where he must reach down. If horses are stabled, all feed and water should be at least as low as knee height or lower. Even if a horse paws or puts his feet in his water tub or feed box, this is healthier than having his feed and water too high.”
“They take smaller mouthfuls of food, more thoroughly chew it, and better mix it with saliva, which helps reduce the risk of choking and impaction colic.
Improved Nutrition – Since horses chew more and the hay or grain mixes better with saliva, food is better prepared for breakdown in the digestive tract. As a result, more vitamins, minerals, and nutrients are absorbed from the food.
Reduced Irritants – Your horse inhales less irritants when he eats with his head down. He also reduces the risk of irritants falling into his eyes. A lowered head also promotes airway drainage, which helps flush out any inhaled dust or hay particles.”