What Is Laminitis or Founder and How Is It Treated?
The daily rainfall in our area over the past few weeks has produced a beautiful new blanket of grass. This affects our front yards and our horse pastures. If your horse eats large amounts of green grass it could possibly develop laminitis. Laminitis is a result of the disruption of blood flow to the laminae structures in a horse’s foot. The laminae structures secure the coffin bone (the wedge-shaped bone within the foot) to the hoof wall. Inflammation (often permanently) weakens the laminae and interferes with the bond between this bone and the wall of the hoof. In severe cases, the bone and the hoof wall separate. In these cases, the coffin bone may rotate within the foot, be displaced downward (“sink”), and eventually penetrate the sole. Laminitis can affect one or more of an animal’s feet, but it is most often occurs in the front feet.
The terms “laminitis” and “founder” are used interchangeably. Founder usually refers to a chronic (long-term) condition associated with rotation of the coffin bone, and acute laminitis refers to symptoms associated with a sudden initial attack, including pain and inflammation of the laminae.
What Causes Laminitis?
While the exact reason the feet are damaged remains a mystery, certain situations can cause laminitis. Laminitis occurs in the feet, but the underlying cause is often a disturbance somewhere else in the horse’s body. The causes vary and may include the following:
- Digestive upsets due to grain overload (from excess grain, fruit or snacks) or sudden changes in diet.
- 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,” and is more common after large amounts of rain causes vegetation to begin growing again.
- Toxins released within the horse’s system.
- High fever or illness. Any illness like Potomac Horse Fever, which causes high fever or serious metabolic disturbances, has the potential to cause laminitis.
- Severe colic.
- Retained placenta in the mare after foaling.
- Excessive concussion to the feet, often referred to as “road founder.”
- Excessive weight-bearing on one leg due to injury of another leg or any other alteration of the normal gait.
- Various primary foot diseases.
- Bedding that contains black walnut shavings.
- Prolonged use or high doses of corticosteroids may contribute to the development of laminitis in some horses, although this remains a controversial possibility.
What Are the Risk Factors of Laminitis?
The factors that seem to increase a horse’s susceptibility to laminitis, or increase the severity of the condition when it does occur, include the following:
- Heavy breeds, such as draft horses
- Overweight body
- Feeding on large amounts of carbohydrate-rich meals
- Ponies, Morgans, miniature horses and donkeys
- 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.
- Horses who have had previous episodes of laminitis
- Older horses with Cushing’s disease
What Are the Signs of Laminitis?
Signs of acute laminitis include the following:
- Rings in the hoof wall that become wider as they are followed from toe to heel.
- Bruised soles or “stone bruises.”
- Widened white line, commonly called “seedy toe,” with occurrence of seromas (blood pockets) and/or abscesses.
- Dropped soles or flat feet.
- Thick, “cresty” neck.
- Dished hooves, which are the result of unequal rates of hoof growth. The heels grow at a faster rate than the rest of the hoof, resulting in an “Aladdin-slipper” appearance.
What Are the Treatment Options for Laminitis?
The sooner treatment begins, the better the chance for a horse’s recovery. Treatment will depend on specific circumstances but may include the following:
- Diagnosing and treating the primary problem, since laminitis is often due to a systemic or general problem elsewhere in the horse’s body.
- Dietary restrictions that temporarily cut out all grain-based and pasture feeding. You may be advised to feed your horse only grass hay until advised otherwise by your veterinarian.
- Your vet may treat laminitis with mineral oil via a nasogastric tube to purge the horse’s digestive tract, especially if the horse has overeaten.
- Administering fluids if the horse is ill or dehydrated.
- Administering other drugs such as antibiotics to fight infection. Anti-endotoxins are used to reduce bacterial toxicity. Anticoagulants and vasodilators may be prescribed to reduce blood pressure while improving blood flow to the feet.
- Stabling the horse on soft ground such as sand or shavings without black walnut, and encouraging the horse to lie down in order to reduce pressure on the weakened laminae.
- Your vet may need to open and drain any abscesses that develop.
- Cooperation between your veterinarian and the farrier. Helpful techniques often include corrective trimming, frog supports, and therapeutic shoes or pads.
- Your veterinarian may be able to advise you on new therapies such as standing your horse in ice water to prevent the onset of laminitis after a predisposing cause such as a retained placenta or a known grain overload.
Long-term Care for Laminitis
Some horses that develop laminitis make uneventful recoveries and go on to lead long, happy lives. Unfortunately, other animals suffer such severe, irreparable damage that they are, for humane reasons, euthanized. Your equine practitioner can provide you with information about your horse’s condition based on radiographs (X-rays) and the animal’s response to treatment. Radiographs will show how much rotation of the coffin bone has occurred and may also illustrate abscesses or gas accumulation that will affect the therapy of your horse. This will help you make a decision in the best interest of the horse and help your farrier with the therapeutic shoeing.
Treatment for Recurring Laminitis
It’s important to note that once a horse has had laminitis, it may be likely to recur. A horse may develop a chronic case of laminitis because the coffin bone has rotated within the foot and the laminae never regain their original strength. There may also be interference with normal blood flow to the feet as well as metabolic changes within the horse. Extra care is recommended for any horse that has had laminitis, including:
- A modified diet that provides adequate nutrition based on high-quality forage, digestible fiber (beet pulp) and oil. Avoid excess carbohydrates, especially from grain. Speak to your vet to come up with a custom meal program for your horse.
- Routine hoof care, including regular trimming and, in some cases, therapeutic shoeing. Additional radiographs may be needed to monitor progress.
- A good health-maintenance schedule, including parasite control and vaccinations, to reduce the horse’s susceptibility to illness or disease. Contact Carolina Equine Hospital for a general wellness exam for your horse.
- Potentially adding a nutritional supplement formulated to promote hoof health. Biotin supplements are popular for promoting hoof growth.
- Avoid grazing lush pastures, especially between late morning and late afternoon hours, since plant sugars are the highest during these times. Restrict pasture intake during spring or anytime the pasture suddenly greens up after lots of sudden rain.
The best way to deal with laminitis is to routinely take prevention of its causes that are within your control. Keep all grain stored securely and out of the reach of horses and sneaky ponies. Introduce your horse to lush pasture very slowly. Be aware that when a horse is ill, under stress or overweight, it is especially at risk. Consult your veterinarian to create a good dietary plan for your horse’s specific needs. Provide good, routine health and hoof care. If you suspect laminitis, consider it a medical emergency and notify your veterinarian immediately.
Equine Veterinary Services in Guilford County, NC
If you need emergency equine veterinary services in Guilford County, NC, call Carolina Equine Hospital at 336.349.4080. The veterinarian is available for emergency visits 24 hours a day, and you can speak with them directly outside of regular office hours by following the prompts in the phone menu. Our team is always here to provide the best possible care for your horse and help you understand all the prevention and treatment options available. You can also schedule an appointment online for regular equine veterinary services.