What is tying-up?
Tying-up is one of the most misunderstood and controversial syndromes in athletic horses. Tying-up is a broad-scale syndrome or description of a horse with muscle damage that has many different causes. Since there are several causes, some of which appear to be inherited, there is no single cure. Symptoms of tying-up include stiffness, sweating, and reluctance to move. Some horses tie-up sporadically and are likely experiencing excess exercise, electrolyte depletion, or dietary imbalances. Other horses can suffer from chronic episodes of tying-up that can be debilitating. Research indicates that a common cause of tying-up is an inherited abnormality in the way calcium is regulated by the musculoskeletal system. The disease might lie dormant unless specific factors trigger the calcium regulatory system to malfunction. Triggering events include stress, excitement, lameness, high grain diets, and exercise at submaximal speeds.
How do you treat a tied-up horse?
If a horse ties up, do not force the horse to walk. Stop exercising the horse and move it to a box stall. Blanket the horse if the weather is cool and determine if the horse is dehydrated due to excessive sweating if the weather is hot. Provide the horse with small, frequent sips of water if the horse id hot and provide free access to water once the horse has cooled down. Relieve the horse of any anxiety and pain. Provide the horse only hay until signs subside. Small paddock turnout is good once the horse starts to walk freely. If the problem recurs, have the horse evaluated for a specific cause of exertional rhabdomyolysis.
Valberg, Stephanie. Tying-Up. American Association of Equine Practitioners, aaep.org/horsehealth/tying.