Fit not Fat
The word laminitis strikes fear into any any horse owner who who has experienced it, but not many people realise that it isn’t just fat ponies in the spring who can succumb to the condition. Spillers’ nutritionist Sarah Nelson examines the risk factors
WITH THE WARMER months on the horizon many owners will be concerned about laminitis. It is a condition that affects 3-5% of the equine population and involves damage to —or failure of —the laminae. These tissues which attach the pedal bone to the hoof wall can be the source of varying degrees of pain and lameness.
What causes laminitis?
In general, most cases of laminitis fall into one of the following categories:
■ Hyperinsulinemia associated laminitis (HAL).
■ Laminitis that is related to inf lammation or toxemia; for example, as the result of a retained placenta or a severe infection, such as pneumonia and grain (cereal) overload.
■ Mechanical laminitis or supporting limb laminitis, which occurs as a result of excess weight-bearing due to an infection or injury in the other leg.
HAL is now considered the most common form of laminitis and includes episodes associated with pituitary pars intermedia dysfunction (PPID/Cushing’s) or equine metabolic syndrome (EMS), and possibly the majority of those previously described as ‘pasture associated’ laminitis.
The exact sequence of events that leads to the development of laminitis continues to puzzle vets and scientists, but HAL may be triggered by eating too much non-structural carbohydrate (NSC) or starch and sugar from feed or forage. This, in turn, causes a sufficiently high or persistent increase in the levels of insulin circulating in the blood, although exactly how this leads to laminitis is still not clear.
Who is at the greatest risk?
Although any horse or pony can develop laminitis at any time, risk factors include…
■ A high intake of NCS (starch and sugar).
■ Insulin dysregulation.
■ Low adiponectin.
■ Genetics; for example, certain native breeds are more predisposed to the condition.
■ PPID, especially in the presence of insulin dysregulation.
■ A history of laminitis.
■ A recent change in grazing or a move to higher quality grazing, regardless of the season.
■ Recent weight gain and obesity, particularly in horses and ponies wi
