The role of nutritional therapy in the treatment of Equine Cushing's syndrome and laminitis - Equine Cushing's/Laminitis

Alternative Medicine Review, Sept, 2001 by Joyce Harman, Madalyn Ward

Higher levels of protein (up to 14%) and calories may be needed in underweight horses, but should not be fed to normal or overweight horses. (53,54) Cushing's horses that are normal weight or underweight often do well on senior diets, which are higher in protein and fat. Many chronic laminitis horses lose weight due to the stress of walking in pain, and actually need increased amounts of feed. The practitioner often restricts feed in a laminitic horse; however, some horses need extra calories to maintain normal physiologic functions. Increased calories can be given as fats (vegetable oils or rice bran) and are well digested by most horses. Increasing total calories with oils may be preferable to using high-protein feeds and hays.

It is important to supply high-quality supplements to help these horses heal. Prepared foods do not have all the vitamins needed by a sick animal. However, formulated supplements which contain low-quality vitamins and added fillers may actually cause the horse's system to become more out of balance. Food-source vitamin-mineral supplements include blue-green algae, kelp, apple cider vinegar, carrots, and oranges. Several companies manufacture additive-free equine supplements.

Antioxidants

Coenzyme Q10 (CoQ10) is useful in reversing free radical damage secondary to sepsis from an endotoxin overload. This is thought to occur with CoQ10 acting as an oxygen free radical scavenger, thus stabilizing mitochondrial membranes, and by inhibiting the arachidonic acid metabolic pathway and the formation of inflammatory prostaglandins. (55) Clinically, CoQ10 seems to be one of the best antioxidants for use in laminitis cases. Pain decreases rapidly when COQ10 is used without concurrent NSAIDs. The therapeutic dose is 300-600 mg per day for the first two weeks; then the dose can be decreased slowly to a maintenance dose of 100 mg per day.

Vitamin C is an excellent antioxidant that can regulate the phagocytic process in endotoxic shock, mainly by decreasing free radical production. (56) Vitamin C is also an important nutrient for collagen production and provides immune system support. Doses range from 3-8 g per day. Horses tolerate these doses well with few cases of diarrhea or stomach irritation.

Other antioxidant nutrients that may be useful are vitamin E, superoxide dismutase (SOD), and dimethylglycine (DMG). These antioxidants are generally used by the authors in the more refractory cases.

Minerals

One of the most important aspects of a nutritional program for horses is the use of free-choice minerals with salt fed separately. Many laminitis horses eat large quantities of minerals for extended periods of time, indicating their need for minerals. A commercial salt-mineral block contains about 94-percent salt, so a horse that does not crave salt will not consume the amount of minerals it needs. The authors have observed horses consuming large quantities of minerals when provided mineral supplementation with salt fed separately.

Several key minerals are needed to help a Cushing's horse with glucose metabolism. Magnesium affects insulin secretion and insulin's action in the cell. Magnesium also helps the cell be more flexible and permeable to insulin. (57) Chromium increases the cell's sensitivity to insulin binding and glucose uptake. Chromium has been shown to be effective in reducing fasting blood sugar levels. (58,59) Vanadium or vanadyl sulfate has actual insulin-like effects on glucose metabolism, (60) helping transport glucose into the cell. (61)