Equine Metabolic Syndrome (EMS) is a complex disorder involving the horse's endocrine system, characterized by obesity and insulin resistance. One of the major complications with this disease is its association with recurrent or chronic laminitis in affected horses. EMS is similar to Metabolic Syndrome (MetS) and Type 2 diabetes in humans.
EMS occurs most frequently in obese horses with regional clusters of body fat, however it is also found in horses with a leaner body condition. These horses are often labeled as "easy keepers" or "good doers" for they are able to maintain their body condition with little feed required.
EMS horses often have a characteristic fat distribution showing deposits such as cresty neck and at the comb, side of the chest, hip region, and tail head. Horses with EMS have a predisposition towards laminitis and often develop it due to grazing in green pasture. Sometimes the horse may have previous history of laminitis or has had mild episodes of laminitis that were mistakenly attributed to foot soreness following a farrier visit, sole bruising, or arthritis.
Clinical signs include a cresty neck score greater or equal to 3 our of 5, a body condition score
equal to or greater than 7 out of 9, insulin resistance, enhanced oxidative burst, and a predisposition to laminitis.
The primary treatment goal for horses with EMS is to maintain the horse's body condition score at a seven, ideally a five. This is usually accomplished through conducting a nutrition analysis, modifying the horse's diet accordingly (usually includes switching to a low-carbohydrate diet and regularly soaking hay), and establishing a regular exercise program.