Dr. Elizabeth MacDonald Talks Endocrine Diseases with Equine Science Class 

Beginning with the clinical signs of PPID, Dr. MacDonald explained the difference between horses presenting with early or mild signs, like delayed shedding or decreased performance, and advanced signs such as regional adiposity, laminitis, or an increase in the severity of the horse’s early signs. She then discussed the usual diagnostic testing and treatment options. Often treatment requires a combination of medication and an extreme diet regimen.

Dr. MacDonald then discussed EMS, another common endocrine disease that results from a combination of risk factors including insulin dysregulation, increased fatty composition, and reduced ability to lose weight. Horses with a genetic predisposition are also more likely to develop EMS. These breeds — ponies, warmbloods, and gated breeds — are considered “easy keepers.” She concluded her talk with diagnosis and management of EMS, which, unlike PPID, can only be treated through a change in diet and exercise. 

The talk ended with a Q&A portion, where Dr. MacDonald answered questions about why heavy draft breeds are not classified as high risk for EMS, what signs show that a horse with PPID is being well managed, and the advantages of soaking hay versus using a hay steamer. Dr. MacDonald’s talk gave us a better understanding of the challenges that come from not keeping horses a responsible weight and how to care for a horse that has developed Pituitary Pars Intermedia Dysfunction or Equine Metabolic Syndrome.