Laminitis: Prevention and treatment

Every day veterinarians across the country see hundreds of cases of laminitis, a painful disease that affects the horse's feet. What is especially alarming is that most cases are preventable. In fact, it may be that we are killing our horses with kindness.

Consider that a common cause of laminitis is overfeeding -- a management factor that is normally within our control.

By learning more about laminitis and its causes, signs and treatments, you may be able to minimize the risks of laminitis in your horse or control the long-term damage if it does occur.

Laminitis defined

Laminitis results from the disruption of blood flow to the laminae. These laminae structures within the foot secure the coffin bone to the hoof wall. Inflammation often permanently weakens the laminae and interferes with the wall/bone bond. In severe cases, the bone and the hoof wall can separate. The pain and physiologic effect is similar to hitting your finger with a hammer and eventually loosing your nail. In these situations, the coffin bone may rotate within the foot, be displaced downward ("sink") and eventually penetrate the sole. Laminitis can affect one or all feet, but it is most often seen in the front feet concurrently.

The terms "laminitis" and "founder" are used interchangeably. However, founder usually refers to a chronic (long-term) condition associated with rotation of the coffin bone, whereas acute laminitis refers to symptoms associated with a sudden initial attack, including pain and inflammation of the laminae.

Causes

While the exact mechanisms by which the feet are damaged remain a mystery, certain precipitating events can produce laminitis. Although laminitis occurs in the feet, the underlying cause is often a disturbance elsewhere in the horse's body. The causes vary and may include the following:

&middot Digestive upsets due to grain overload or abrupt changes in diet.

&middot Sudden access to excessive amounts of lush forage before the horse's system has had time to adapt; this type of laminitis is known as "grass founder."

&middot High fever or illness; any illness that causes high fever or serious metabolic disturbances has the potential to cause laminitis

&middot Severe colic.

&middot Retained placenta in the mare after foaling.

&middot Excessive weight-bearing on one leg due to injury of another leg or any other alteration of the normal gait.

&middot Although controversial, prolonged use or high doses of corticosteroids may contribute to the development of laminitis in some horses.

Risk factors

&middot Obesity

&middot High nutritional plane (feeding large amounts of carbohydrate-rich meals)

&middot Ponies, Morgans, miniature horses and donkeys

&middot Unrestricted grain binges, such as when a horse breaks into the feed room (if this happens, do not wait until symptoms develop to call your veterinarian-- call immediately so corrective action can be taken before tissue damage progresses)