Laminitis in Horses & Hoof Health
By: Dr. Lydia Gray, SmartPak Medical Director/Staff VeterinarianBrief Description
Laminitis is inflammation of the laminae, the tiny, interlocking fingers that attach the coffin bone to the hoof wall. A complex sequence of events occurs during laminitis, potentially altering blood flow or circulation in the foot, resulting in damage to this tissue. When the damage is severe enough, the laminae die and the coffin bone is no longer supported in the hoof. If the bone rotates or sinks in the hoof, the horse is said to have “foundered”.
The leading cause of laminitis is pasture (grass sugar) overload, but it can occur after any number of compromising conditions in the body, including:- Grain (sugar) overload
- Colic or diarrhea
- Uterine infection or retained placenta
- Equine Metabolic Syndrome (Insulin Resistance) or Cushing’s Disease
- Excess weight-bearing on a limb
- Infections in the blood, lungs or other organs
- Shifting weight from foot to foot
- Painful-looking gait (described as “walking on eggshells”)
- Classic founder stance (leaning back so hind feet bear more weight)
- Warm feet, bounding digital pulses
- Sweating, increased heart and respiratory rates
- Reluctance to move or get up from lying down
Supplements that May Lend Support
Research has shown that ingredients such as essential fatty acids and hops may have the ability to interrupt the cascade of negative effects leading to laminitis after sugar, starch, and fructan overload. Once a horse has developed laminitis, there may still be a role for omega 3 fatty acids because of their properties which offset dangerous inflammatory effects. Other ingredients such as the antioxidant Vitamin E target the oxidative stress associated with this condition and may also be appropriate. Horses that develop laminitis due to Insulin Resistance from either metabolic or endocrine conditions may benefit from supplements that contain chromium and magnesium, which have been demonstrated to support proper insulin and sugar metabolism. Finally, because healthy hoof regrowth is important, hoof supplements that contain biotin, methionine and other amino acids, plus zinc and other minerals may be recommended.Possible Diagnostic Tests
Your veterinarian will perform a complete physical examination to determine the extent of the laminitis and attempt to discover what may have caused it. He or she may take x-rays initially as a baseline, and again a few weeks later to look for differences in the position of the coffin bone.
Prescription Medications Available
Generally, most horses with laminitis benefit from non-steroidal anti-inflammatory drugs (NSAIDs) like bute (phenylbutazone) for pain and swelling. If the laminitis is due to a gastrointestinal disturbance such as colic or diarrhea, Banamine® (flunixin meglumine) may be given to fight endotoxins. Antibiotics will be administered if infection is present. Sometimes medications that dilate blood vessels, such as acepromazine or isoxsuprine, are given to help encourage better circulation in the foot. Horses that develop laminitis due to Cushing’s should receive daily Prascend® (the FDA-approved version of pergolide) to manage the underlying condition. Thyro-L® (levothyroxine) is being investigated as a treatment for the Insulin Resistance seen in Equine Metabolic Syndrome and may be a useful prescription drug in the battle against laminitis.
Other Management Suggestions
It is very important to provide mechanical support to the hoof during a bout of laminitis, and your veterinarian and farrier should work together to accomplish this. At first, stall rest may be recommended. Later, as the horse becomes more comfortable, short periods of hand walking may help increase circulation to the damaged hoof tissue.
Depending on the cause of the laminitis, your horse may be put on a restricted diet. If caused by pasture or grain overload, or if Cushing’s or Equine Metabolic Syndrome are suspected, then grass, grain, treats and other foods high in sugar may be off limits. A vitamin/mineral supplement may be necessary to meet minimum nutrient requirements for horses on restricted diets.
Questions to Ask Your Veterinarian
- Why did my horse develop laminitis?
- Is he now more likely to develop it again?
- Will I be able to ride him again?
SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.
