Laminitis refers to inflammation of the tissue which connects the pedal bone to the hoof wall. It is characterised by hot and painful feet and obvious lameness when moving. The lameness may vary from a mild shuffling to an actual reluctance to move or may get to the point where the horse is too sore to even stand.
Severe cases may progress to a point where the inflamed connections (laminae) actually give way and the pedal bone separates from the hoof wall, the tip of the bone being forced down towards the sole.
The causes of laminitis are many and varied, as the term laminitis refers to all conditions in which the connective tissue is damaged and becomes inflamed and painful.
The simplest cases are concussive laminitis, which, as the name suggests, is the resultant damage from excessive loading on the foot while working. Pounding the ground (particularly at the gallop on firm surfaces) overloads the connective tissue and leads to tearing of some of the laminae.
Treatment involves the use of anti-inflammatory drugs, reduced workload until the hoof repairs and ensuring regular and correct farriery. Low heel long toe foot conformation is a contributing factor in this type of laminitis, and unfortunately has become quite common in modern thoroughbred types.
Concussive laminitis should be differentiated from the following more severe problems which involve the whole animal (these are called systemic diseases).
The first is the typical FAT PONY PROBLEM. Overweight/obese animals are more susceptible to laminitis as excess fat stored in the body over time affects the function of other organs. Chronic fat overload disrupts liver function and leads to reduced tissue sensitivity to insulin. As a result, glucose is not removed efficiently from the blood into tissues such as muscle (this is similar to the problem with people who are chronically overweight and subsequently develop diabetes).
This high level of blood glucose stimulates more insulin production and it is probably this high circulating insulin level that actually triggers a laminitic episode. These horses also seem to over respond to a carbohydrate meal (one that contains sugars and starches), resulting in an excessive increase in insulin which may then trigger the problem.
It is clear then that management of these horses focuses on 1) reducing bodyweight and 2) restricting access to water soluble carbohydrate (WSC = starch + sugar). This can be achieved by a combination of exercise to help burn off body fat, and the feeding of low energy high fibre feeds.
To achieve this;
The Thompson & Redwood “Claytons Pellets” are a no grain, low WSC pellet suitable for feeding as part of the ration for these horses.
The second common cause of laminitis is FEED INDUCED. Even horses in normal or thin condition can be at risk if they are suddenly given a meal excessively high in very digestible carbohydrate.
Although they can efficiently digest starch and sugar in the small intestine, even horses used to concentrates can get into trouble if they receive a meal excessively high in WSC. Problems can occur at two levels; firstly, the sudden surge in blood glucose may induce an over response to insulin production and trigger a laminitis event directly.
Secondarily, the level of starch and sugar may exceed the digestive ability of the small intestine and soluble carbohydrate will escape into the large intestine. Oversupply of starch to the hind gut can induce a toxic acidic environment, causing the death of some species of micro organisms. Under extreme conditions, this will also be toxic to the whole animal and cause laminitis.
Horses that are adapted to grain have a hind gut population that is also adapted to utilising some starch, and it is only under extreme conditions that they will run into trouble. This is obvious since most horses that are doing regular exercise and competition are on cereal grain based rations and are in good health.
So, here are a few rules to help keep them healthy:
Light Work – 3kg conc. 8kg rough.
Moderate Work – 4kg conc. 6kg rough
Heavy Work – 5kg conc. 5kg rough.
Thompson & Redwood make a range of feeds to suit all horse needs. These have been scientifically formulated to provide a safe palatable basis for your horses’ rations, using only the best quality local produce.
Additionally, the Dodson and Horrell ‘Lami-Free’ Herbal blend is now available to purchase in Australia. Formulated in 1993, it contains three different wild crafted herbs. The main ingredient, nettle, is a natural antioxidant and reputed to support the circulatory system.
Seaweed and Rosehips are also included to contribute to the nutritional support for healthy hoof growth, which can vary widely between horses. All of these herbs are suitable to be part of the dietary support for horse or ponies prone to, or who have suffered from laminitis in the past. They can be purchased from the T&R online store.