Laminitis manifests in the foot and results in varying degrees of pain, lameness and debilitation. There are several causes of laminitis and currently these are divided into three main categories: sepsis/systemic inflammatory conditions, endocrine/metabolic disturbances, which includes pasture associated laminitis, and mechanical overload. Being able to identify animals at increased risk of laminitis, as well as the potential risk factors, is obviously key to reducing the incidence of the condition.
Two new studies have been conducted in collaboration with the WALTHAM® Equine Studies Group. The first evaluated the laminitis risk factors in a group of Danish horses and ponies.1 It confirmed that Cold-blooded type animals <149 cm, such as certain native ponies, as well as those being kept on high quality pasture, were at an increased risk of developing laminitis for the first time. It also highlighted the important role that a change in grass intake, in terms of both type and amount, may play at any time of the year not only the spring as commonly thought.
The second study evaluated the risk factors for the development of laminitis prior to the occurrence of the disease.2 It identified that low concentrations of the adi-pose tissue derived hormone adiponectin, together with high serum insulin concentrations (at rest and as part of a diagnostic test for PPID), may predict an increased risk of future pasture-associated laminitis. It is hoped that future studies will be able to generate more robust cut off values, which will more accurately predict future laminitis development in an individual animal.
The RVC, in collaboration with WALTHAM®, is currently taking this forward through a study in which these markers are measured regularly, in conjunction with a detailed management assessment, in a group of ponies with no known history of laminitis at the start.
The Danish study gives us important practical facts about the susceptibility of cold-blooded types, and is particularly applicable to natives in the UK. The second study gives hope that there may soon be a test or series of tests that will help predict those at an increased risk of suffering from pasture-associated laminitis in the future thereby reducing the number of animals affected by this debilitating condition. In the meantime until we fully understand the condition it is sensible to manage all the risk factors we currently know about, in particular encouraging clients to keep their horses at a healthy weight.
How to keep horses safe from laminitis all year round:
- Do not turn out cold-blooded types onto new, high quality pasture.
- Restrict grass intake. Even winter grass can be a significant contributor to excess calories. A horse or pony can consume up to three times its normal daily energy requirement in just 24 hours at grass. Consider using an appropriately fitting grazing muzzle for part of the day and/or restrict time out at grass, although body condition still needs to be monitored as some animals can still consume a considerable amount in a short period of time.
- Keep regular track of your horse's body condition — try using the SPILLERS BCI calculator and Body Condition Scoring tool via your mobile or tablet device.
- Increase exercise if appropriate to do so, not only to help your horse or pony lose or maintain a healthy weight, but also to help keep the metabolism healthy.
- Provide an appropriate amount (not less than 1.5% bodyweight per day on a dry matter basis) of an alternative low calorie forage source. Replacing pasture with suitable (less than 10% (on a dry matter basis) water soluble carbohydrate (WSC), hay, haylage or a forage replacer will help replicate natural browsing behaviour while controlling calories and WSC intake.
- Avoid feeding cereals or cereal-based feeds, opt for a balancer or if additional calories are required look for a high oil, high digestible fibre, low starch and sugar option.
- Provide daily vitamins and minerals to balance the diet, an appropriate feed balancer is ideal for this purpose.
- Do not over-rug overweight horses and ponies especially if they are natives or unclipped. Let them burn calories to keep warm.