Laminitis—the inflammation of the soft tissues of the hoof—is one disorder you hope to never see. Once the chain of events that leads to laminitis has been set in motion, it cannot be reversed. And if the delicate laminae that support the coffin0 bone within the hoof capsule give way, the resulting internal deformity (founder) requires many months of recovery, and some horses may never regain soundness.
To learn more about laminitis and laminitis symptoms, download a FREE guide—Learn About Chronic Laminitis in Horses: The risk, prevention, symptoms and treatment of this hoof disease.
The good news is that ongoing research is revealing more and more about the causes of laminitis, which in turn is helping to identify and protect the horses most at risk.
April is EQUUS’s Laminitis Prevention Month because lush spring grass is responsible for so many cases. But in reality, laminitis can strike in any season. Now is a good time to review your laminitis prevention measures, but it’s important to maintain your vigilance year round.
1. Identify at-risk horses. Any horse can develop laminitis under the right circumstances, but some—such as those who are insulin0 resistant or have Cushing’s0 disease—are much more vulnerable to the disease. To assess your own horse’s risk, go to “What’s Your Horse’s Laminitis Risk?” (page 26). If you answer “yes” to any of the questions, your horse is at increased risk for laminitis, and you need to take appropriate precautions.
2.Keep your horse’s weight in check. Obese horses, especially those with “cresty” necks and fat deposits around the withers and tailhead, are more prone to laminitis. The research isn’t yet clear on why fat deposits in those particular locations are linked to laminitis—one current theory is that the fat in the crest of the neck secretes substances that interact with the endocrine0 system. If your horse is overweight, develop a plan to reduce his calories and increase his exercise. If you’re unsure about his body condition or how to change his feed and exercise plan, ask your veterinarian for guidance.
3.Limit your horse’s intake of sugars and starches. Grains are rich in starches and sugars, also known as nonstructural carbohydrates (NSCs). The equine stomach cannot digest large amounts of NSCs all at once, so they pass into the intestine and hindgut intact, where they ferment and produce byproducts that kill the normal gut flora. This triggers the cascade of inflammatory events that ultimately leads to laminitis.
A classic example of this process is seen in the horse who breaks into a feed room, overindulges on grain and develops laminitis. But the overload is not always so dramatic: A horse with other risk factors can develop laminitis after eating only a “normal” serving of grain if it is high in NSCs. Many pleasure horses can get along fine on hay alone; if your at-risk horse needs more calories, look for a commercial feed formulated to be low in NSCs.
4.Get to know your grass. The majority of laminitis cases are linked to pasture grass, especially when the plants are rich in another NSC, a plant sugar called fructan. Cool-season grasses (and hays made from them), such as fescue, rye and bluegrass, are typically higher in fructan than warm-season grasses such as bermuda or switchgrass.
That said, the fructan level of any grass fluctuates throughout the year, and peaks often occur in spring and fall. A laboratory analysis is the best way to determine the sugar content of your pasture grasses: Your veterinarian or local extension agent can help you find a facility and then interpret the results. Testing your grass periodically in different seasons will help you identify patterns and make better decisions about when to allow at-risk horses to graze.
5.Use a grazing muzzle. Another way to make turnout safer for an at-risk horse is to outfit him with a grazing muzzle. These devices, which cover the mouth and nose, limit the amount of grass he can eat while still allowing him to drink. Different models are available that either attach to a halter or hang from their own crownpiece. If you choose to use a grazing muzzle, make sure it is adjusted properly and that it stays on—some horses get very good at removing them.
6.Create a dry lot. When fructan levels peak, a dry lot—a paddock with no grass at all—can be the ideal turnout location for at-risk horses. Obese or insulin-resistant horses or those with a history of laminitis may do best if kept in a dry lot year-round. Keep in mind that horses on a dry lot will need ample hay to protect their digestive health. Giving them plenty of hay will also likely prevent them from chewing on fences and trees.
7.Make any dietary changes gradually. This bit of advice may be old but it’s not outdated. Sudden changes in diet can disrupt the balance of digestive flora in a horse’s gut, which can lead to laminitis. When switching to any new type of feed—including hay—blend the new with the old in steadily increasing amounts over the course of at least a week.
8.Tend to a horse’s “good” foot when he’s injured. Pasture-associated laminitis accounts for about 70 percent of all cases, but a horse who has sustained a serious injury in one leg is also at an increased risk of developing laminitis in the opposing limb, which must bear more than its share of weight while he convalesces. In cases like this, your veterinarian and farrier will work with you to help support the uninjured leg to lower the risk of laminitis.