The Horse | Recognize Insulin Resistance Before Laminits Onset

The Horse | Recognize Insulin Resistance Before Laminits Onset

Recognize Insulin Resistance Before Laminits Onset

by: Alexandra Beckstett, The Horse Feature Editor
January 06 2012, Article # 19396

Early detection and intervention are key to managing any disease process. With laminitis, picking up on the subtle signs of hyperinsulinemia (high levels of insulin in the blood resulting from insulin resistance) before the horse suffers a serious laminitic event is one way caretakers and veterinarians can try to halt the hoof disease in its tracks. At the 6th International Equine Conference on Laminitis and Diseases of the Foot, Donald Walsh, DVM, of the Animal Health Foundation, in Pacific, Mo., described easily detectable changes in hoof growth that might hint at the development of hyperinsulinemia and laminitis.

Laminitic changes associated with hyperinsulinemia start and progress slowly. Walsh believes abnormal division of insulin basal cells (the bottom cell layer of the epidermis) and stimulation of insulinlike growth factor receptors on laminar cells cause the laminae, which connect the horse's hoof to the coffin bone, to stretch and lengthen. "If hyperinsulinemia is not addressed and blood insulin levels normalized (through diet, exercise, and appropriate medication), then continued abnormal hoof growth may lead to further weakening of the laminae and the development of laminitis," he explained.

Early signs of hoof damage due to hyperinsulinemia can include abnormal growth rings in the external hoof wall, separation of the hoof wall from the white line when looking at the bottom of the horse's foot, and a "seedy" toe (increased width of the white line, where the sole and the hoof wall meet) as the laminae weaken. Small areas of hemorrhage (caused by damage to the laminar vessels) in the seedy toe area might also be visible.

This process can be "somewhat reversible," Walsh said, if caught early. Thus, "owners need to look for abnormal hoof growth, have their veterinarian check the horse's insulin levels, and institute a low-carbohydrate diet and exercise program (even 10 minutes a day is beneficial) and medical treatments to restore (normal) insulin levels," he concluded.

Regarding trimming and caring for these horses' feet, Walsh suggested farriers move the breakover back to reduce stress on the laminae; leave a little excess hoof wall on the sides of the foot to reduce sole pressure; and cauterize the seedy toe to prevent bacteria from entering.