If your vet utters the word “laminitis” when assessing your horse, it strikes straight to the heart of the horse owner.
This can be a life-altering (or life-ending) diagnosis of a problem that has been misunderstood for a long time. This is such a key topic in the horse world that recently there was an International Equine conference on ‘laminitis and diseases of the foot,’ held Nov. 1-3 in West Palm Beach, Fla. Much time, energy and research is being devoted to this problem in horses and some of the new results are changing our ideas about the problem.
So what is laminitis?
In simple terms, the laminae are tiny, interlocking ‘fingers’ of two different kinds of tissue that connect the inside of the horse foot to the outside. Some of the ‘fingers’ come from the inner layer of the hoof wall (you see the outside of the hoof wall as the actual hoof). These ‘fingers’ interlock with ‘fingers’ coming from the inside that have lots of capillaries, nerves and other structures. Inflammation of these ‘fingers’ or laminae can have disastrous results where the laminae pull apart in a structural failure. This in turn can lead to a bone inside the foot (the coffin bone) changing position (rotates) with very painful results for the horse. This displacement of the coffin bone is called ‘founder’ – it can vary from mild (very small movement) to acute and crippling.
Symptoms of laminitis vary from subtle to extreme. Warning signs can be ‘cresty’ necks, uneven rings showing up in the hooves (founder rings indicative of improper diet), bounding pulse in the foot, posturing trying to get the weight off the front feet, shuffling the feet trying to get comfortable.
There are multiple causes of laminitis. Current research identifies three different types of laminitis caused by different triggers. Probably the most common type is the one caused by obesity or metabolic disorders.
Another type is the inflammatory one where the horse has become systemically ill and there is organ inflammation. An example would be a horse that has problems in the large or small intestine due to an overload of carbohydrates – too much food.
Other causes in this category include bacterial disease, potomoc horse fever, infection in the lungs or contact with black walnut shavings (causes systemic inflammation). The third type is a weight-bearing cause where a horse is protecting an injured limb by putting more weight on the limb on the other side. Also too much stress on the feet can cause trouble (e.g. ‘road founder’) where the horse has spent a lot of time trotting on a hard surface.
Treating laminitis can be a challenge. By the time you see that you have a problem, your horse has already been in trouble for some time. A very effective treatment for the inflammatory form of laminitis is icing the foot – this quickly aids in reducing inflammation and helping to relieve the pain. Padding the foot or stabling in deep, supportive bedding can also help reduce the discomfort. Non-steroidal anti-inflammatory drugs can make the horse more comfortable.
The goal for horse owners should be prevention of laminitis. The article ‘The Anatomy of Laminitis’ by Laurie Banner in EQUUS Issue 427, Laurie identifies six ways to prevent laminitis.
The six are: limit access to lush pasture, particularly for at risk horses; reduce the carbs and sugars in your horse’s diet; keep hooves in good shape; do not let Cushing’s disease go unchecked; watch your horse’s weight; and protect your horse’s ‘good’ limb after an injury.
Management is the key to preventing laminitis so do your homework, keep track of what your horse is eating and look out for your equine friend.
