Understanding laminitis


Laminitis is defined as a weakening of the bond between the epidermal lamellae (attached to the outer wall) and the dermal lamellae (attached to the third phalanx). It can occur to varying degrees. If this weakening persists and progresses, the tearing of the lamellae will result in instability of the third phalanx (P3), compression of the sole, veins and arteries of the hoof. The horse will be extremely sore and its mobility will be greatly reduced or even impossible. If a rotation of P3 and/or a lowering of P3 in the hoof capsule (distal descent) are radiologically observed, this state is called founder.


If your horse suffers from laminitis, you must first identify the cause as laminitis is not in itself a disease but usually the consequence of a series of metabolic disorders (equine metabolic syndrome or EMS), the two main causes being insulin resistance (IR) and Cushing's disease. It’s estimated that more than 80% of laminitis cases are the result of these disorders. In the United States, more than one million horses are diagnosed annually, or about 20% of the horses. Other much rarer causes are, for example: systemic infections (such as Potomac fever), accidental ingestion of large amounts of carbohydrates (such as grains), the overloading of a limb for long periods of time, for example when the opposite limb is fractured.

I will focus here on horses suffering from equine metabolic syndrome (EMS) since the vast majority of laminitis cases are related to these problems.


Laminitis resulting from metabolic disorders


If you try and help a horse that is foundered due to metabolic disorders without addressing the diet or treating Cushing's disease with medication if diagnosed, all efforts to trim it will be in vain. As the American laminitis specialist Pete Ramey says so well, ‘’you can't trim your way out of founder''.


The ECIR Group is an American non-profit society whose primary purpose is to help metabolic horses. According to their findings, insulin resistance (IR) is not a disease but a set of genetic factors that make some horses particularly sensitive to non-structural carbohydrate (NSC) levels in their diet. They cannot be cured; rather, we must learn to manage the factors that can trigger high insulin levels, which in turn will cause laminitis in this individual.


Signs of insulin resistance (IR):


  • The horse gains weight easily and is often obese

  • Lack of energy (seems lazy)

  • Abnormal fat deposits such as on the neck, tail base, sheath, shoulders

  • Swelling above the eye

  • Insulin levels are high but the glucose level is normal

  • A history of laminitis, often after being on pasture

  • Excessive wall deviation (stretching of the white line)

  • Sensitive hooves, thin sole. When riding, the horse is always looking for softer ground

  • Horizontal lines visible on the outer wall


A healthy weight


If your horse is at high risk, the first thing to do is to check if your horse's weight is at a healthy level. Ideally, we look for a body score between 4.5 and 5.5 on the Body Condition Score Chart. If your horse is overweight, a reduction in calories is necessary. Never reduce below 1.5% of your horse’s current body weight in hay or 2% of his ideal weight.  That being said, it’s likely that your horse will be hungry, especially at the beginning when the amount of hay he is used to is reduced. Hay nets with small holes (less than an inch in diameter) are very useful to slow down consumption. We want our horse to eat often, but in small amounts to keep his insulin level stable. Personally, I like the slow feeding nets from N.A.G. nets. They are affordable and very durable.


The management of the metabolic horse requires a low supply of carbohydrates and fat combined with balanced vitamins and minerals.  All types of grains, processed feeds, and fresh grass must be completely removed until the insulin level is regulated. It is even possible that some horses may never be able to eat them again. The ECIR Group recommends that any feed (hay or supplement) be tested in the laboratory and show a NSC level of 10% or less.


Not all laboratories calculate carbohydrate levels in the same way, which can be confusing. In Quebec, the Agri-Analyse laboratory calculates this rate as recommended by the ECIR Group. While waiting for your results, it is recommended to soak your hay for 1 hour in water and drain it before serving it in order to significantly reduce water-soluble sugars. Ideally, hay will be offered at 10% or less HCNS.


The incidence of iron in the diet and metabolic problems


Research is still ongoing, but it appears that blood iron levels in horses may affect insulin resistance and possibly Cushing's disease. The ECIR Group has found that many horses have greatly improved when iron levels have been closely controlled. The two most important sources of iron in horse a horse’s diet are water and minerals. Some weeds are also high in iron. The filtration of iron-rich water combined with the addition of low iron minerals are therefore two things to consider if you are in the presence of a horse with chronic laminitis or founder. Below are links to scientific articles on this subject.


How to feed an insulin-resistant horse (IR)


  • Eliminate all supplements/treats that contain sugar (carrots, commercial candies, etc.)

  • No access to grass until the IR is controlled. Possible access with a muzzle in the future.

  • Hay tested at 10% NSC or less. If the NSC’s are higher, soak for at least 1 hour and drain to reduce water-soluble sugars.

  • Straw can be added (tested at 10% NSC or less) to meet chewing and fibre requirements without adding too many calories.

  • Some of the fibre can be replaced by adding molasses-free beet pulp (or soaking and draining) and/or Ontario Dehy Timothy Balance cubes which have a guaranteed 10% HCNS analysis.

  • Feed 3 to 4 times a day with nets. Start with 2% of the ideal body in hay. If the horse does not lose enough weight in the following months, reduce to 1.5%. For example, at 2% a 500 kg horse would have 10 kg of hay/day.

  • Add minerals and vitamins with very low sugars (NSC) and low iron content.


After much research, I found that the Canadian company MadBarn offers the lowest iron levels on the market in addition to having no sugar in their formulation. Either Omneity P (low iron level) or Aminotrace + (very low iron level), developed in association with the ECIR Group, are good choices. Mad Barn also makes a supplement specifically to help insulin-resistant horses, the Magnechrome.


Add omega 3 to help reduce inflammation and regulate insulin. Freshly ground flaxseed is an option that provides ALA type omega 3s. Feed up to 500g /day. There are also good commercial oils made especially for horses but make sure that they are high in omega 3, not in omega 6. W-3 oil (DHA) oil is a good choice. ​​


Therapeutic approach


Over the years, a great deal of research has been carried out on the physiology of the hoof as well as on metabolic disorders. Several long-accepted theories have now been denied. Veterinarians and researchers such as Dr. Robert Bowker of the University of Michigan and Dr. Debra Taylor of Auburn University in Alabama, Dr. Eleanor Kellon and farrier Pete Ramey to name a few, have demonstrated that new approaches are needed both to counter the emergence of insulin resistance and Cushing and to rehabilitate hooves affected by laminitis. 


The protocol that is still encountered most often today, with a generally poor prognosis, is the following:


  • Not enough emphasis on the diet, apart from eliminating access to grazing. We forget to analyze the supplements and complete rations that are offered to horses. Many products that are offered as low in NSC are in fact far too high for IR horses, despite what companies want us to believe through their marketing.

  • Perform fasting blood tests and/or checking only the glucose level with strips and a human glucose tester. These can yield false negatives and testing sugar alone is not a valid test as it's the ration of glucose to insulin that is important.

  • Raising the heel (to supposedly reduce tension on the deep flexor tendon). This has the effect of forcing the horse's weight towards the toe, exactly where the lamellae are inflamed and fragile. If you look at a foundered horse, you can see that it is trying to load its heel by rocking onto its heels to find comfort.

  • Preventing any movement with stall confinement. This drastically limits circulation which is counterproductive.

  • Applying a heart-bar shoe or fitting a shoe on backward. Any shoeing will apply more stress to the inflamed lamellae by peripherally loading the hoof onto the wall.

  • Recommending soaking the hooves several times a day in ice. This practice has many disadvantages; lifting the feet is a great challenge for the client and the horse who is in pain, the soaking makes the entire hoof more pliable and less able to resist the pressure imposed on them and the cold limits the circulation in an already compromised foot. The only case where ice has been shown to be beneficial is in laminitis induced by sepsis (such as following a high fever). Icing the hooves for 48 to 72 hours without interruption can prevent the release of endotoxins to the feet. The majority of laminitis cases are caused by high insulin levels for which ice will not only be of no benefit but may even worsen the situation.


Here are the new protocols that are recommended by veterinarians and farriers who have obtained impressive results: 


  • Test the horse for glucose, insulin and Cushing's to identify the cause of laminitis.

  • Any food consumed by the horse must contain 10% or less of non-structural carbohydrates (NSC).

  • Monitor hay quantities systematically by weighing hay to establish daily portions to achieve weight loss when necessary.

  • Add omega 3 and balanced minerals.

  • Be careful to reduce the amount of iron absorbed. Filter water if necessary and check iron levels in vitamin and mineral formulas offered to horses.

  • Blood samples must be not be taken on a fasting horse, but fed with hay only. We want to compare the ratio of glucose to insulin. The leptin level can also be measured. A high leptin level is an indicator of a horse's high risk of becoming insulin resistant. It helps to avoid false negatives.

  • Lower the angle of P3 to the ground to less than 10 degrees. Do so by adjusting with small increments using frequent trims and never more than 10mm at the time.

  • Apply a mustang roll to the wall to relieve the pressure on the laminae.

  • Distribute the load over the entire foot (with boots and pads 24 hours a day), which will reduce the load on the laminae (what shoeing would impose). See tips on how to succeed with this approach on the booting for rehab page.

  • Allow the horse to move in soft terrain, in a limited and/or controlled manner with protection as long as a heel-first landing can be obtained. It is the compression/decompression of the hoof that will restore blood circulation. A horse confined to a stall won't move thus maintaining the hooves in a constant compression situation, which hinders healing.

  • Increase the movement gradually as the horse improves.

  • Use anti-inflammatories if necessary according to the veterinarian's recommendations accompanied by medication (omeprazole) or supplements to limit possible gastric disorders such as ulcers (Visceral+ from Mad Barn is an excellent one).

  • Include complementary therapies such as laser, massage therapy, and acupuncture if possible to help the horse feel better.


To learn more, I encourage you to look at the following links:


Rehabilitation Protocol for Pete Ramey and Dr. Debra Taylor 


Pete Ramey on laminitis


Pete Ramey on the descent of P3


Video conference with Dr. Debra Taylor on what describes a healthy hoof 


Study that shows that the theory of increasing the angle of P3 is counterproductive


Study that discusses the importance of horse movement in the case of laminitis 


Research on problems related to iron levels:


Iron overload in horses by Dr Kellon


Equine insulin resistance high iron, Dr. Frank K. Reilly

 You can view some of my case studies where the owner and I followed as much as possible the
recommendations of the previously detailed protocol and the results obtained.