What happens if a horse eats to much grass?

It all depends on what the horse does or what symptoms they show after over eating. Horses will ALWAYS eat too much grain if given the opportunity (such as getting loose & breaking into the feed room, etc) so it also depends on how much they have eaten. Some horses can eat too much grain and suffer no ill effects at all but that's not common. Most horses will colic or founder. Colic is basically a very bad stomach ache that can be extremely painful and even fatal. Colic is a horse owners worst fear. At the first sign of colic, it is a good idea to go ahead and call the vet. While waiting for the vet, do not let your horse roll on the ground because their intestines can get twisted which is almost always fatal. Keep them up and keep them walking until the vet gets there. The walking helps keep their mind off of their pain but more importantly, keeps them from rolling and can sometimes help them to pass the painful gas or have a bowel movement, which will help. Founder is a little different but can have longlasting negative effects. It affects their hooves and can cause lameness. In the past, horses that have foundered were often thought to be permanently lame but that is no longer the case. Practices of Natural Hoof Care have discovered ways to help horses recuperate from founder and often make a full recovery. Natural Hoof Care is currently experiencing a tremendous rise in popularity in all horses circles, including many well known professionals. For more information, scroll down this page to the links to Jaimie Jackson & Pete Ramey's websites. These two men are really making a positive different in the horse world! A horse overeating is a very serious matter. When feeding, its a good idea to always measure your horses food and ALWAYS keep feed securely locked away where they can not get into it