Dietary Management of Endocrine Disorders in the Older Horse

Control of ration quantity and composition is important in the management of horses with pituitary pars intermedia dysfunction (PPID) or equine metabolic syndrome (EMS) that exhibit obesity and/or hyperinsulinemia. In obesity, restriction of daily dry matter intake to 1.25% to 1.5% of current body weight will facilitate weight loss and improvement in insulin sensitivity in most horses, although the rate of response will vary between animals and more severe restriction (dry matter intake 1.0% body weight) may be needed. Access to pasture grazing should be limited during management of obesity (eg, use of grazing muzzles). Insulin resistance and hyperinsulinemia may persist after weight loss, dictating the need for long-term restriction of dietary nonstructural carbohydrates ( 10–12% dry matter), including restricted pasture grazing. Author’s address: Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, 736 Wilson Road, East Lansing, MI 48824; e-mail: [email protected]. © 2013 AAEP.