Obese senior horses may suffer from Equine Metabolic Syndrome (sometimes improperly referred to as hypothyroidism or peripheral Cushing's disease). These horses tend to store excess fat, especially along the crest of the neck, over the shoulders, on the rump, and in the sheath (geldings), and often exhibit chronic laminitis. Horses affected with Equine Metabolic Syndrome may also exhibit insulin resistance, in which blood glucose (sugar) is not adequately removed from the blood via the hormone insulin.
At this time, Equine Metabolic Syndrome is not completely understood, but it is believed by researchers that obesity, as well as a genetic susceptibility, are important predisposing conditions. If Equine Metabolic Syndrome has been diagnosed, it may be helpful to reduce the amount of starch and sugars in the horse's diet to help decrease the amount of blood glucose. Purina® Equine Senior® horse feed is formulated to contain reduced levels of starch and sugars, and has been fed successfully to many horses with this condition. Purina® WellSolve L/S® horse feed is also an appropriate option for insulin-resistant older horses. Additionally, it is important to consider hay- and/or pasture-fed horses in these situations, since grasses can contain high levels of soluble carbohydrates (starches and sugars).