Springtime means sunshine, green grass, and risk of laminitis!

by Barbara Noble

With the warmer weather and another early spring, laminitis is a good topic for all horse owners to have on their mind. Our northwestern grass will soon be growing high, and also high in sugar. All horse owners could benefit from knowing about the risk of laminitis, and being proactive in preventing it, whether or not their horse is showing symptoms. Horses prone to laminitis of the most common variety are thought to be horses with an inherited gene which predisposes them to obesity (the easy keeper type) and a different metabolism of carbohydrates. Even if your horse does not have laminitis, you can be proactive and possibly avoid this condition altogether.


The lamina are the interconnected tissues that hold the hoof—the hard outer shell—onto the coffin bone, which joins the hoof with the leg. Laminitis is a reaction in those interconnected tissues, the lamina, which loosens the hold between the hard hoof and the bone. The loosening causes the tissues to stretch or separate and even bleed and can be agonizingly painful for your horse.

If your horse has laminitis there are very important management steps to take: the management mantra for laminitis is “1) diagnosis 2) diet 3) trim 4) exercise”. All are important, though in this article I am focusing on step two—diet as a preventive measure.

Careful and knowledgeable grass management for your horse is crucial. Websites such as safergrass.org will give you up to date information on grass and more. I also recommend having your hay cored and analyzed so a balancing supplement can be formulated. Mineral balancing improves the overall health of the hoof and seems to also improve the way the horse handles glucose. Freedom Farm has its hay analyzed each year, and offers this kind of supplement for clients.

The actual cause of this carbohydrate-induced laminitis is high insulin. The insulin resistant (IR) horse, as they have come to be known, has an insulin level that without great diet control just keeps getting higher until the feet break down. The feeding of fat has also been demonstrated to support insulin resistance and is vigorously discouraged by the Yahoo Equine Cushings and Insulin Resistance Group.  In another article, I can provide various considerations related to ‘feeding fat’.

Human studies show a link between magnesium and insulin resistance with low levels making IR worse. This supports using magnesium in the hay balancing mix or being sure to include it as, for example, in a calming supplement.  Another mineral important in a negative way is iron. Iron overload in horses increases insulin resistance which you now know increases the chance of laminitis and is also found increased in Cushings disease.  The effects on a horse from a life with too much iron consumption can slowly be improved with diet balancing. Unlike humans who need a steady supply of iron in our food, horses have no mechanism for losing iron, except hemorrhage. The iron they take in just keeps building to a higher level.

Again, sugar and starch, which are carbohydrates, are high in our fresh spring grass. Manage and moderate your horse’s grass intake. Remember too that your horse’s metabolism may be changing. The young horse without diet issues may now be the middle aged horse with insulin resistance. Your veterinarian can do blood work checking for leptin resistance or even do insulin : glucose ratios to establish your horse’s baseline levels or to detect abnormalities.

Every year, people call Freedom Farm for help with their horses suffering from laminitis! Need your horse off grass? We have facilities for the healthy horse who needs to avoid grazing, and special pens for those who need time to recover. We'd much rather you catch it early! Contact Mary Gallagher by email or phone if you are concerned about your horses.