When tackling laminitis, hoof-care professionals understand there are many causes. Yet one of the less recognized causes of laminitis is equine metabolic syndrome (EMS).

What Causes Equine
Metabolic Syndrome?

A number of symptoms and associated conditions related to equine metabolic syndrome include:

  • Obesity
  • Cresty neck
  • Insulin resistance
  • Laminitis
  • Pot belly appearance
  • Lethargy
  • Excessive thirst
  • Increased tendency for colic
  • Delayed shedding of winter coat
  • Gastrointestinal disturbances
  • Abnormal fat deposits, such above the eyes and fat accumulation at the root of the tail

Unfortunately, EMS is sometimes confused with Cushing’s disease, which is another related endocrine disorder. EMS was first recognized more than a decade ago by veterinarians who have compiled a lengthy list of clinical symptoms including obesity, insulin resistance and laminitis.

While there is no cure for EMS, lifestyle and diet changes can help the health and well being of these affected horses and reduce the possibility of laminitis with problem horses. EMS is sometimes recognized when chronic laminitis becomes evident in fat horses that tend to avoid foundering.

With horses living longer, University of Minnesota equine veterinarian Christie Malazdrewich says owners are more interested in preserving health, athletic function and quality of life for horses. She finds obesity is a major concern with horses suffering from EMS.

“Body fat, especially stored in the abdomen, liver and skeletal muscle, contain cells that are very active metabolically and hormonally” she says, “When present in excessive amounts, their effects can trigger a cascade of metabolic disturbances leading to insulin resistance and persistent hyperglycemias. These abnormalities can lead to the increased synthesis and release of cortisol within the peripheral tissues of the body, which may account for the predisposition to laminitis in affected horses.”

Confusion, Disagreement

Equine veterinarians Frank Gravlee and Scott Gravlee find considerable confusion and disagreement in the scientific literature regarding EMS. The equine nutrition consultants with Life Data Labs in Cherokee, Ala., say EMS exists as a series of symptoms ranging from mild to life threatening that involve all of the metabolic systems of the horse. However, the degree of the symptoms depend on the stage of severity and the length of time the horse has been affected.

These equine vets say a combination of symptoms is often the basis for the disparity and confusion that exists with diagnosing EMS. Once the horse has progressed past being overweight or developing into an easy doer, it becomes a veterinary challenge for diagnosis.

Blood work is needed to diagnose insulin resistance, hypothyroidism or hyperadrenocorticism. Excessive caloric intake, especially from sugars and starches, can be the root cause of EMS. In addition, deficiencies of dietary iodine and tyrosine can lead to hypothyroidism.

Proper Nutrition Is Essential

Dr. Lydia Gray says EMS often occurs in middle-aged horses ranging from 8 to 18 years of age. The medial director and staff veterinarian for SmarkPak Equine in Plymouth, Mass., says EMS-affected horses should not be fed grain, have little or no access to pasture and be fed low sugar grass to limit the intake of starches and sugars. Since this kind of hay may not meet all of a horse’s nutrient requirements, EMS horses may need a multi-vitamin/mineral supplement.

Frank Gravlee says the prevention and management of EMS was one of the major goals in developing the Life Data Labs Barn Bag Adult Maintenance product. This product provides a horse with the required daily nutrients while controlling calorie intake and offers needed amounts of tyrosine and iodine to nutritionally maintain the thyroid gland.

This program usually eliminates the need to feed concentrates or grain by balancing the diet with an efficient roughage diet. To eliminate as many carbohydrates as possible from the diet, vegetable oil or beet pulp can be fed as an additional calorie source to maintain body condition.

Exercise Needed

EMS horses with laminitis often receive limited exercise or no exercise due to the instability of the laminae. Gray says EMS horses need some type of controlled exercise, such as hand-walking, lunging or riding. With these conditions, many owners find strict calorie-counting diets are difficult and stressful to maintain. These owners worry that horses on a strict diet that are stabled for long periods often in solitary conditions suffer a poor quality of life.

Some EMS-affected horses struggle to lose weight, particularly in obesity prone animals or good doing horses that spend most of their time outside. These horses normally benefit from the addition of an anti-adipocyte compound to speed up weight loss and help regulate insulin and glucose levels.


At this winter’s International Hoof-Care Summit, SmarkPak Equine’s medical director and equine veterinarian Lydia Gray is conducting a Hoof-Care Classroom on what farriers need to know when it comes to dealing with overweight and underweight horses. The Summit is being held from January 28 to 31 in Cincinnati, Ohio.

In addition, Frank Gravlee and Life Data Labs are sponsoring the Burney Chapman Memorial Lecture in honor of the well-known deceased Texas farrier at the Summit. Ohio farrier Randy Luikart will be sharing his ideas on how a farrier’s work affects the weight-bearing phase of equine locomotion.

To get a copy of the 12-page 2014 International Hoof-Care Summit program, click here.