You’ve heard the words murmured like catchphrases in the tack room at the barn, by the farrier’s truck, and even at Happy Hour amongst your horsey friends. You’ve always nodded your head in understanding, but after a while it all gets confusing. Once and for all, what is the difference between equine Cushing’s disease, equine metabolic syndrome, and hypothyroidism?

Here we’ll help make sense of these three conditions.

Pituitary Pars Intermedia Dysfunction (Cushing’s Disease)

Commonly known as equine Cushing’s disease, pituitary pars intermedia dysfunction (PPID) is a progressive syndrome affecting older horses. Common clinical signs include weight loss; a long, thick hair coat and delayed shedding; increased frequency of drinking/urination; and chronic laminitis (an inflammation of the laminae–the interlocking leaflike tissues attaching the hoof wall to the coffin bone). A loss of muscle mass along the horse’s topline and sagging abdominal musculature can also cause the affected horse to develop a pot-bellied appearance