The Misunderstood 10% Rule

Metabolic disorders affect all types of horses and ponies and are caused when the body’s normal metabolic process’ are altered. Correct management of horses and ponies suffering from metabolic disorders is crucial in reducing the risk of problems, such as laminitis, which are closely associated with metabolic issues. For horses to maintain body condition and perform well, regulation of diet is key. Whether your horse is a good doer or a poor doer, all horses with metabolic disorders require a diet which provides a low glycaemic response as well as being low in sugar and starch.

THE 10% RULE

Sugar and starch are classed as non-structural carbohydrates (NSC’s) and to manage a horse suffering with metabolic issues effectively, guidelines state that the NSC content of the TOTAL diet should be maintained at 10% or less. This includes the NSC’s provided by forage, as well as concentrate feed. When taking your horse’s sugar consumption into consideration, it is important to therefore assess the sugar that is provided through their forage ration. The sugar content of grasses will vary depending on the weather, time of day, stage of growth, plant species and geographic region. These factors also apply to conserved forages alongside the time of year that they were cut. Starch is also found in forage, but it is generally feedstuffs that will supply the horse with most of their starch intake. Removing feedstuffs that contain cereals, such as oats, barley, wheat, and maize will help to reduce your horses starch intake.

When looking at your horses concentrate feed, it is important to not just consider the % outlined on your horse's bag of feed, and to understand what this contribution will provide in terms of grams or kilos.

For example, if your forage has a combined starch and sugar of 7% and you are roughly feeding 10kg this will provide 700g of starch and sugar. If you are then feeding 2kg of a feed with a combined starch and sugar of 15% this will provide 300g of starch and sugar. Combined this is a total of 1kg of starch and sugar per day. The combined 12kg of feed and forage will therefore have a starch and sugar content of 8.3% for the ration as whole, less than the recommended 10%.

DID YOU KNOW?

For horses with metabolic conditions, having your forage analysed to determine it's NSC content is a valuable way of understanding whether it is a suitable forage source for your horse or pony. If analysis suggests a high sugar content, soaking the hay can be an effective way of maintaining fibre intakes whilst reducing the number of NSC's in the ration. Recent research has found that soaking hay for just 15 minutes significantly reduced the WSC value of the forage. The 'optimum time,' to soak forage for is often disputed, as soaking hay for long periods of time can alter the bacterial profile of the hay, and can increase the risk of digestive issues. We therefore suggest soaking hay for no more than 60 minutes in cold water, or 30 minutes in warm water. This has been shown to reduce starch and sugars levels while not increasing bacterial growth to a potentially dangerous level.