Laminitis, more commonly referred to as founder, is an extremely serious condition that requires prompt treatment for the best possible outcome. With founder, the sensitive laminae of the hoof become inflamed. In the early stages of founder, the horse will rock back onto his hind legs in an attempt to relieve pressure off the front feet (where it most likely occurs). As the disease progresses, he might refuse to walk or eat. Symptoms include heat at the coronary band and a strong pulse that can be felt at the ankle. The pain is often intense and will probably be accompanied by a sickly or stressed appearance.
Early detection can prevent extensive and irreversible death of laminae tissue. If laminae tissue is damaged like this, the foot will not be able to support the coffin bone, resulting in the downward rotation of that bone. If discovered too late or left untreated, permanent damage to the supporting structure of the foot will result. This can often mean the end of a horse's usefulness and/or the beginning of a chronic condition.
Early Warning Signs
The onset of laminitis will cause extreme pain to your horse's feet. Usually, it is the front feet that are affected, but it is not unheard of in the hind feet. Your horse will rock back onto his hind legs in an exaggerated pose, attempting to remove all weight off the front feet. He will be reluctant to walk and might even lie down. He might show further signs of pain such as sweating, rapid breathing, and he could possibly run a temperature. The feet will be very warm to the touch and a strong pulse can be felt in the digital artery, located over the fetlock joint.
Arteries run down either side of the leg and can be seen on the inside and outside of the fetlock. To feel for a horse's “digital pulse,” place two fingers on either one of these arteries. A strong throbbing is an indication that there is a problem in the foot, since inflammation will cause constriction of blood vessels. On a healthy horse, this pulse is steady and barely noticeable.
Laminitis can be a secondary sickness, occurring after surgery, a major illness, or from a high temperature. But the most common causes of laminitis are:
Grain Founder: 90 percent of all founder is grain founder. It is an ingestion of above normal, spoiled, or a different type of grain than a horse is used to. This is common when a horse gets loose overnight and gets into the feed room. Like a dog, a horse will eat himself sick. However, unlike a dog, the horse cannot vomit to relieve himself.
Water Founder: Laminitis can be triggered by ingestion of water when a horse is still hot from exercise. This is common when an overworked horse that has lost a lot of electrolytes through excessive sweating is immediately placed back in a paddock or stall with water available to him.
Grass Founder: This is caused by ingestion of too much rich pasture or legume hay, such as alfalfa. This is common in the spring, when horses that have been without any grass all winter are indiscriminately placed on pasture or paddock grass instead of being slowly acclimated to this feed. Also, rich second cut legume hay should be mixed with grass hay, at least until the horse is used to it.
Road Founder: This is less common, but occurs by repeated and excessive pounding on a hard surface for long distances. City bound horses, such as police and carriage horses, are subject to road founder.
Time is of the essence and often determines whether laminitis will be cured or will become chronic. A veterinarian should be called out at any sign of possible founder. In all cases, grain should be removed from the horse's diet. Oils can be given orally to purge the system of toxins. Removing the shoes and soaking the feet in ice water every twenty minutes can relieve some of the pain and swelling. An anti-inflammatory should be administered. Forcing the horse to walk in short intervals can also help to increase blood flow to the foot and hoof, as will medications such as isocsoprene. If founder is caught within the first twenty-four hours, administering antihistamines can be enormously beneficial, since founder is caused by a release of histamines that are ever present in the bloodstream of a horse. A horse with chronic laminitis can benefit from corrective shoeing and can remain “pasture sound” or serviceably sound for many years. Ponies are particularly sensitive to laminitis.