Laminitis is the inflammation of the laminae in the hoof. The laminae are interlocking fingers of tissue which arise from the inside of the hoof capsule and surface of the pedal bone to provide a bond between the two. The laminae have many blood vessels which are necessary for thermoregulation, the transport of oxygen and nutrients to the foot and removal of waste products from the foot which is constantly growing and remodelling. The starvation of the blood supply to the laminae can eventually result in the death of the laminae tissue which breaks the bond between the pedal bone and the hoof capsule. The pedal bone can then rotate or founder, causing the horse immense pain and discomfort.

NUTRITION RELATED CAUSES OF LAMINTITIS

There are many causes of laminitis but the most frequently recognised are nutrition related. Nutrition related laminitis occurs due to a carbohydrate overload caused by an excessive intake of cereals or grass. The horse’s digestive system is divided into the fore gut and the hind gut. The horse absorbs protein, fats and oils and some soluble carbohydrates in the fore gut. The hind gut is responsible for the break down of fibre by a process called fermentation. As fibre is made up of complex structures known as insoluble carbohydrates the fermentation process is slow and produces a gradual release of energy. The horse relies on a resident population of bacteria in the hind gut to ferment the fibre. A small proportion of soluble carbohydrates are broken down and absorbed in the hind gut which the horse can normally accommodate. However, if excessive amounts of soluble carbohydrates enter the hind gut the bacteria responsible for breaking down soluble carbohydrates proliferate to cope with the excess. The break down of soluble carbohydrates makes the environment in the hind gut more acidic which results in the death of the other species of bacteria. This releases endotoxins or poisons into the blood stream which affects circulation and results in the laminae being starved of blood.

OTHER CAUSES OF LAMINITIS

• Toxins can enter the blood stream from a source of infection.
• Disruptions to normal gut function such as an episode of colic.
• Trauma can occur if overweight horses and ponies are worked too hard or if horses are worked on hard ground
• Excessive weight bearing to compensate for lameness in the opposite leg

AVOIDING LAMINITIS

The primary aim in avoiding laminitis is to promote healthy gut function through maintaining a balance of the bacteria present in the hind gut and avoiding an overload of soluble carbohydrates. This is best achieved by following the simple rules of feeding.

· feed little and often – cereals are commonly used to provide the horse with extra energy. They contain lots of soluble carbohydrates and so to prevent an over load occurring the concentrate feed should be split into as many small feeds as possible.

· feed according to the level of work being done - over feeding will cause the horse to become over weight and also increases the risk of an overload occurring.

· feed plenty of fibre – a plentiful supply of fibre is important for maintaining the presence of fibre digesting bacteria.

· make changes to the diet gradually – this will allow the bacteria in the gut to adapt to a new diet.

FEEDING HORSES AND PONIES PRONE TO LAMINTITIS

A horse that has suffered from laminitis before will be predisposed to the problem occurring again regardless of the original cause. Avoiding an overload of soluble carbohydrates is the primary objective which can be achieved with different diets depending on the horse or pony’s requirements.

Over Weight Horses and Ponies

It is important not to starve individuals who are over weight as this will disrupt normal gut function and may lead to hyperlipaemia, a disease that involves the rapid break down of fat stores that infiltrate the liver causing damage.

Use low nutritional value fibre sources as long as they do not present a respiratory hazard. Splitting the fibre ration into many small feeds will help to prevent greedy individuals from eating everything in one go and reduce the time the gut is empty.

Although over weight horses and ponies require a low calorie diet they still require a balance of other nutrients such as protein, vitamins and minerals. Baileys Lo-Cal is a low calorie forage balancer that can be fed as the sole concentrate source to provide a balanced diet. Alternatively, you could try Dengie Good Doer.

Under Weight Horses and Ponies

The horse can utilise energy from sources other than soluble carbohydrates. Fibre provides a slow release energy source that horses and ponies are often very efficient at utilising. When the soluble carbohydrate content of grass is removed by drying it creates hay which is the safest feed for horses and ponies prone to laminitis. Individuals requiring extra weight should have unlimited access to good quality hay.

Fats and oils provide a concentrated energy source that is available to the horse in the fore gut. Feeding fats and oils in the form of Baileys Show’n Win or Buckeye Equine Energy will provide the horse with energy that will not affect the function of the bacteria in the hind gut. They can be fed alongside Baileys Lo-Cal or a high fibre compound feed such as Baileys No.2 Working Cubes or Dodson & Horrell Country Cubes.

Using a probiotic supplement will also stimulate improved fibre digestion and efficient utilisation of the concentrate diet, encouraging the horse to make more of the food available to it.

Horses in Work

The basis of the ration should be good quality hay fed to appetite. Avoiding cereals in their grain form is advisable and so feeding a cube ration rather than a mix is beneficial. Baileys No.2 Working Cubes or Dodson & Horrell Country Cubes that are high in fibre would be suitable for horses and ponies in light to moderate work. Buckeye Equine Energy could be added to increase the energy content of the ration safely.

For more information please contact:

Baileys Horse Feeds, Four Elms Mills, Bardfield Saling, Braintree, Essex, CM7 5EJ
Tel: 01371 850247. Fax: 01371 851269. e-mail: info@baileyshorsefeeds.co.uk