Avoiding Nutritional Laminitis and Founder

Laminitis. Founder. Two words that are often used interchangeably but do not actually mean the same thing. Laminitis refers to an inflammation of the laminar tissues in the hoof, tissues that hold the coffin bone in place. Founder refers to an actual rotation of the coffin bone within the hoof. Laminitis does not necessarily lead to founder, but it can if it's not treated quickly. There are several situations that can lead to laminitis or founder, including trauma, concussion, drugs, toxemia, and a diet high in soluble carbohydrates (starches and sugars). Obese horses and ponies, horses that have foundered before, and horses with Cushing's are more prone to founder. Most of these can be managed with some forethought and attention to detail.

Nutritional laminitis is linked to the amount of soluble carbohydrates in a horse's feed. Bouts can be caused by an over consumption of grain, either in one sitting or by feeding large grain meals. A rule of thumb for an average 1000-pound horse is to feed no more then five pounds of a standard mixed grain or pellet at one time.

Laminitis can also be caused by an over consumption of rich spring pasture. Young plants (grasses or legumes, such as clover or alfalfa) are growing rapidly in the springtime, and these plants can be very high in starches and sugars. If the horse's digestive system isn't used to the high level of starch, it can cause digestive problems that can lead to laminitis. Therefore, it is recommended that the horse be introduced to young pastures slowly. They should only be turned out for 1-2 hours each day in the beginning, and slowly the amount of time they're allowed to graze can be extended. This may mean that you have to take the horse off the pasture he's been on all winter and keep him in a stall or a dry lot until he's adapted to the new grass in his pasture.

A more recent concern has focused on the fructans in some pasture grasses. Fructans are a type of sugar that is not digested in the small intestine of the horse, and can reach high levels in cool-season grasses such as orchardgrass, timothy, and fescue. Research suggests that when fructans are consumed, they reach the bacteria in the cecum and are fermented into lactic acid, which can lead to laminitis and founder. Fructan levels tend to rise during the spring and fall; times when the nights are cool, the days are warm, and the grasses are growing rapidly. Horses prone to laminitis should be kept off such pastures. Also, horses that have a history of laminitis or founder, as well as horses that are obese or have been diagnosed with insulin resistance or equine metabolic syndrome are high risk and should have minimal to NO exposure to lush pastures.

Sometimes you may not be able to take your horse off the pasture entirely. If you can at least limit him to a smaller section, particularly one with little grass, it is better then doing nothing. Another alternative is to use a grazing muzzle to limit the amount of pasture the horse can consume in one day, which may keep the horse from foundering. It is also helpful to keep hay where the horse can eat it, particularly if the pasture is lush.

Over-weight or obese horses are more prone to founder as well. You should evaluate your horse's body condition score regularly. If they get to a body condition score of 6 or higher, limit their pasture using the above methods.

The other condition that must be strictly managed involves the Cushing's horse. Horses with Cushing's Syndrome are very susceptible to founder when the starches in their diets change rapidly or get very high. While they may be very thin, you don't want to give them a lot of high-starch grains. Minimizing starch intake is vital for their health and soundness. This means keeping them off the rapidly growing pasture during the early spring and fall seasons, and feeding a low-starch/high-fat grain mix or pellet.

Once you get out of the rapid-growth season, usually April to June in the spring and for a short time during the fall, most horses will be fine if left on the pasture full-time once they've adjusted to it. It is never recommended to just let a horse out on pasture for a long period of time if they've been confined to a stall and only had access to hay previously. These horses, too, must be introduced to the pasture slowly.

If you realize your horse has just eaten an entire bag of feed, or if he's showing signs of founder – warm hooves, bounding pulses in his lower limbs, walking “on eggshells”, or leaning backward in an attempt to keep weight off the front feet – you should call your veterinarian immediately. Early treatment can either stop or at least retard the progress of laminitis and may allow the horse to recover completely.

In addition to your veterinarian's treatment program, Buckeye recommends feeding a grass hay and Gro'N Win (feed ½ pound more per day than what is recommended) to the foundered horse. We do not recommend feeding any additional grain as this will add calories, which is counterproductive at this time. While the foundered horse is healing, it is important that the lowest calorie diet is given to keep additional weight off the feet, while still providing the minerals and vitamins necessary to maintain optimal health. Once the horse has healed, the diet should consist of a low-starch/high-fat mixture. Gro'N Win and one of the Ultimate Finish products work excellently!