Laminitis, sometimes called founder, is a painful and distressing condition of the horse's hoof that leads to chronic, incurable lameness. Some horses are humanely destroyed because of it.
Importance of laminitis research
Few controlled trials have tested dietary supplements or feed additives but researchers are showing interest in magnesim and cinnamon for treatment and prevention of laminitis in horses.
Broadly Laminitis can be divided it to three forms; concussion-induced (cause by fast work on a hard surface), caused by another medical condition (such as Cushings syndrome) or feed-induced. Feed-induced Laminitis is the most common form of laminitis and the type that will be mainly covered by this article. 50% of Laminitis cases could have been avoided with the correct management. Laminitis is one of the biggest killers of horses, second only to colic.
Approximately half of the horses that develop laminitis are on pasture when the disease develops. There are two reasons for this.
- Certain grasses under certain conditions have high levels of fructans, a specific sugar that has been shown to cause laminitis.
- Horses with insulin resistance (IR), a component of Equine Metabolic Syndrome, are predisposed to laminitis and pasture acts as a trigger factor.
For these reasons, horses that have developed laminitis from pasture or that have been diagnosed with IR should be allowed limited to no grazing. Horses with IR should also not have sweet feed, treats with sugar, or anything with molasses in it. An appropriate diet for a horse prone to laminitis from sugar is grass or alfalfa hay and a ration balancer or multi-vitamin/mineral instead of grain.
Little if any controlled trials have tested dietary supplements or feed additives. Areas that could be explored include the role of increased antioxidant supplementation, the importance of additives that may stabilise pH in the hindgut and the role of agents that may help block the activation of the enzymes that break down the lamellae bonds between the pedal bone and the hoof wall.
However, perhaps currently one of the most important areas of interest is around those nutrients or nutraceuticals that might counter either the development of insulin resistance or the effects of being insulin resistant. Two such nutrients that are currently creating some interest are magnesium, which is essential for a horse in its own right and the common spice cinnamon.
Cinnamon may be an unusual spice to feed to a horse but in human medicine there is increasing interest in this spice due to its beneficial effects on insulin sensitivity particularly in people suffering with type II diabetes. It is suggested that even at low doses cinnamon could have significant effects on fasting glucose concentrations. Although no trials have been performed in horses, cinnamon may prove to have benefits effects in laminitic ponies where insulin resistance may be underlying.
In human medicine there has been increasing interest in the potential role of magnesium in supporting the action of insulin. It has been suggested that in humans with type II diabetes with low magnesium status magnesium can improve insulin sensitivity.
So what about horses? Low magnesium status is often not reported in overweight horses or those predisposed to or suffering from laminitis also, but that doesnât mean it doesnât exist.
Researchers are suggesting that more studies are needed to see if magnesium supplementation over and above the level normally provided in the diet does have any beneficial effect on insulin sensitivity and laminitis in the horse. Until then it would certainly seem appropriate to ensure that all horses have an adequate intake of magnesium.