What is Cushing’s Disease and how do you treat it?

We are often asked by visitors who enjoy feeding Ryerss horses during a farm visit, why some horses cannot have apples and carrots. Sometimes the answer to that question is that the horse has Cushing's disease and cannot have these treats. So what is Cushing's disease exactly?

The preferred terminology among veterinarians is Pituitary Pars Intermedia Dysfunction (PPID). PPID occurs mostly in horses 7 years of age or older and is a common hormonal disorder. PPID occurs when there is an abnormal, non-cancerous growth in the pituitary gland. As this growth in the pituitary gland gets larger, it causes the body to produce excessive amounts of cortisol and other hormones. Too much cortisol can have many different negative effects.

What are the symptoms of PPID?

The most common signs of PPID, caused by very high cortisol levels, include:

• excessive hair growth with little or no shedding

• changes in body shape (i.e. development of large, fat deposits along the mane, lack of muscle tone, pot belly

• lethargy

• increased thirst and urination

• prone to infections which may take longer than normal to heal

• laminitis (inflammation inside the hoof)

• weight loss

• ulcers in mouth

How is PPID diagnosed?

A veterinarian must conduct a physical exam on the animal and take blood samples to rule out other issues that could be to blame for the animal’s illness. After these are performed, there are special blood tests that should be run to properly diagnose this condition.

How is PPID TREATED?

Although there is no definitive treatment for equine Cushing’s disease, there are some ways to manage and control it. Because insulin and blood sugar absorption may not be functioning properly in Cushing's horses, dietary management is a must. Horses with PPID are not to be fed high sugar or high starch foods such as traditional grains, treats - like apples and carrots, or pasture grass. A low-sugar, high-fiber feed made specifically for senior horses is most often used. In addition, a drug called pergolide is commonly given to the PPID horse, if it is effective, the veterinarian may then gradually cut back on the dosage. Medication and diet, along with exercise and nutritional supplements for the hoof and coat, are the best ways to manage PPID.

So now you know that treats are fine in limited amounts to most equines but can be harmful to those with Cushing’s disease (PPID). However, if you would like to give treats to these animals, we recommend sugar-free peppermints or sugar-free oatmeal cookies. Even if you don’t bring special treats, all of our residents appreciate the love and attention visitors give to all of them.