Obesity has become the most common nutritional problem of horses in the developed world. The reason is an inability for easy keeping horses to readily adapt to the affordable improved feedstuffs and declining work loads seen with pleasure horses. Horses evolved to take advantage of the good seasonal times with efficient storage of energy that would then get them through the lean times of the year when forage became scarce. As far as food is concerned it has become Thanksgiving everyday and that is the beginning of the Equine Metabolic Syndrome (EMS) story. EMS is essentially a disease of obesity and the resulting insulin resistance which leads to a predisposition to founder. This article discusses the physiological events leading to Equine Metabolic Syndrome, clinical signs, diagnosis, treatment, and prevention of this common problem of some breeds of horses.

Equine Metabolic Syndrome (EMS) is most often seen in middle age, obese horses. There may be a cresty appearance to the neck and geldings may have a sheath that appears swollen because of all the fat deposition. Usually these horses have a body condition of 7 or more, ...more. EMS has a distinct breed predilection and these are usually the "easy keeping breeds". Morgans, Paso's, ponies, and Mustangs. These breeds are all commonly effected by this disease but it can be seen in just about any breed.

Mares may cycle irregularly or continue to cycle through the winter. The feet might have signs of chronic founder with rings and irregular wall growth. Lameness is the most common reason the veterinarian is called. The horse has developed a stiff pottery gait that may have come on slowly over several days. In some cases the hooves show evidence of chronic founder that precedes the current lameness.