Recent research in the UK has highlighted that laminitis affects up to 1:10 horses or ponies. This is a really shocking statistic and equates to two or three cases per livery yard per year. A single bout of this excruciating disease will result in life long changes within the hoof, which could limit a horses ridden career at best, or at worst result in euthanasia. This is a devasting reality given that the majority of laminitis cases are both predictable and entirely preventable if you know what to look for and implement the correct management changes.
What is laminitis?
Laminitis is inflammation of the laminae. The laminae suspend the pedal bone within the hoof capsule and are responsible for preventing the pedal bone from falling through the sole of the foot. When the laminae are inflamed or damaged, they lose their strength, which results in rotation of the pedal bone.
What are the signs?
- Difficultly turning especially on hard ground
- Short, shuffly, lame or reluctant walk or trot
- Hot feet
- Weight shifting from one foot to the other
- Bounding digital pulses
What might put a horse or pony at risk of laminitis?
95% of laminitis cases have an underlying hormonal (endocrine) cause, and in this article we are going to concentrate on these. It is important to point out, when we talk about hormonal or endocrine laminitis, this has nothing to do with moody mares or riggy geldings!
Equine Metabolic Syndrome (EMS): The term used to describe a collection of risk factors for hormonal or endocrine laminitis. The key risk factor for laminitis is insulin resistance, which is commonly caused by being overweight. However, it is possible to see insulin resistance in horses which are not overweight too.
Cushings: An age-related condition which is caused by a tumor in the pituitary gland. This tumor causes an over production of stress hormones that can cause insulin resistance. Cushings disease is often (but not always) accompanied by visual signs such as a curly coat, regional fat deposits and a pot belly.
Careful management of horses and ponies with EMS can reduce the severity of the disease in many cases, whereas Cushings disease will require lifelong medication.
How can I reduce the risk of my horse or pony developing laminitis?
To be able to prevent a problem, we must first understand how it was caused, and what the risk factors are. Then, we must make changes to avoid these risk factors.
How: Focusing on endocrine laminitis, we know that high levels of insulin in the blood induces laminitis. High levels of insulin are most commonly the result of being over-weight.
- Recent weight gain doubles the risk of developing laminitis
- Soreness after hoof trimming is a key indicator a problem is developing and triples the risk of developing laminitis
- Having already had an episode of laminitis increases the likelihood of the horse or pony having another episode
Key Steps to avoid these risk factors:
- Monitor and assess weight on a weekly basis especially during the spring and summer
- Schedule regular farrier visits, ideally every 5-6 weeks
- If changes are noticed by your farrier, or your horse is sore after being trimmed or shod, make contact with your vet to discuss your concerns
- Implement a management plan to reduce high blood insulin
How to reduce high blood insulin
- Prevent insulin peaks by avoiding high sugar or starch food
- Encourage and maintain healthy weight loss all year round
- Prioritize exercise
The presence of sugars in the digestive system stimulates the release of insulin. For the majority of the leisure horse population the key sources of sugar in the diet are grass and hay/ haylage.
The sugar content of grass is highly variable, and will depend on the weather, season, length of the grass and species of grass. For horses at risk of laminitis, or those who need to lose weight grass intake must be limited year-round, but especially in the spring, summer and early autumn. The University of Liverpool have put together a great resource on alternative grazing methods for horses.
The sugar and energy content of hay and haylage are also very variable and requires forage analysis to work out the exact levels. This is not an expensive service, and is offered by many feed companies and equine nutritionists. It has been proven that soaking hay for 12-16 hours will reduce the insulin response when it is eaten. It has also been shown that haylage of equivocal energy and sugar content to hay results in a higher insulin response.
The most important thing to understand when feeding hay for weight loss is that most UK hays contain too much energy (or calories) for the majority of our native horse and pony population that are in light work or resting. The main energy source for horses in hay is digestible fiber, rather than sugars. In fact, the large majority of UK hay has a low sugar content (less than 10%). To allow our horses and ponies to maintain a healthy level of dry matter intake (kilos of food eaten per day) while loosing weight, it is essential that we reduce the energy density of the food. The best way to do this is to feed hay with a low energy, and also soak it for 12 hours. Where it is suitable, feed oat or barley straw as a proportion of the total fiber intake as straw has a far lower energy density than hay and has the added benefit of making the horse feel fuller for longer.
Lastly, exercise plays a key role in maintaining insulin sensitivity. A recent study has shown just 20 minutes of low intensity exercise a day can significantly improve insulin regulation. This could be as simple as taking the pony with you when you walk the dog! Exercise should only be undertaken if the horse or pony is comfortable.
It is important to acknowledge that while the energy (or calorie) content of the diet needs to be restricted for weight loss, the availability of vitamins, minerals, quality protein and anti-oxidants should not. Providing a small feed with a low calorie balancer is a great way to ensure nutritional requirements are being met. Where access to grass is restricted, it is important to provide your horse will additional vitamin E, a vital anti-oxidant which is even more important if a diagnosis of EMS or Cushings has been made. WellHorse Veteran is a complete vitamin and mineral balancer, with additional levels of key anti-oxidants vitamin E and vitamin C, as well as joint and digestive support.