Equine Cushing's Disease vs.
Equine Metabolic Syndrome
There's a new disease in town, and its name is Equine Metabolic Syndrome. Unfortunately,
it's difficult to diagnose, has no specific treatment and can lead to laminitis.
It can also look just like a condition you're probably already familiar with, Cushing's
Disease. Fresh from the AAEP Annual Convention, here's an update on what we know
about these two disorders and how to manage them.
Equine Cushing's Disease is a disease of older horses, with signs first developing
in horses when they are between 18 and 23 years of age. These signs include:
Right now the best tests for Cushing's Disease are the dexamethasone suppression
test and the ACTH stimulation test, following a complete physical examination and
regular bloodwork. And while the disease cannot be cured, pergolide seems to help
manage the disease better than cyproheptadine. In general, horses with Cushing's
should be fed a low glycemic index diet, that is, sugars and starches should be
kept to a minimum. This may mean limited to no pasture or grain for some horses.
Certain supplements (described below) may help support and maintain healthy metabolic
function in these horses.
- hirsutism (long curly hair)
- weight loss and muscle atrophy
- depression and poor performance
- normal to increased appetite
- fat deposits along the crest of the neck, over the tail head and above
Equine Metabolic Syndrome, on the other hand, typically affects horses earlier in
life, when they are between the ages of 8 and 18. Pony breeds, domesticated Spanish
mustangs, Morgans, Peruvian Pasos, Paso Finos and some warmblood breeds seem especially
prone. The main signs of this syndrome are obesity, laminitis and fat deposits as
Diagnosis begins with a complete physical examination and regular bloodwork and
may include glucose tolerance testing or a new, combined glucose-insulin tolerance
test. Unfortunately, there are no medications to treat Equine Metabolic Syndrome.
At this time, experts recommend a low sugar/starch diet, exercise and antioxidants
such as Vitamin E to help manage the oxidative stress that comes with the syndrome.
Research shows other products such as herbs, amino acids, vitamins and minerals
may support and maintain proper metabolic function in horses with either Cushing's
Disease or Equine Metabolic Syndrome. Scientific and word-of-mouth evidence exists
for the following ingredients:
If you think your horse may have one of these diseases, contact your veterinarian
right away for a diagnosis. The sooner medical and nutritional support is provided,
the better your horse's chances are of avoiding serious complications.
- Banaba Leaf Extract -May increase insulin sensitivity
and improve hyperglycemia
- Biotin -May enhance insulin sensitivity and glucokinase
activity in the liver
- Bitter melon -May help stimulate insulin release and
glycogen synthesis in the liver
- Chromium -A component of glucose tolerance factor
(GFT) which potentiates the action of insulin
- Cinnamon -May increase glucose disposal by enhancing
translocation of glucose transporter 4 (GLUT-4)
- Fenugreek -May have hypoglycemic properties
- Magnesium -Cofactor of many enzymes involved in glucose
metabolism and is required for both proper glucose utilization and insulin signaling
- Plant adaptogens -Extracts of certain plants appear
to have insulinotropic and hypoglucagonemic actions
- Taurine -Amino acid that may act as a minor insulin
Cushing's vs. Metabolic Syndrome
By: Lydia F. Gray, DVM, MA
SmartPak Staff Veterinarian and Medical Director