Research has shown that pasture-inducedlaminitis occurs at times of rapid grass growth. The accumulation of certaincarbohydrates including fructans, starches, and sugars known as Non-StructuralCarbohydrates (NSC) in pasture forage during the spring, early summer and autumn,particularly after rainfall precipitate this laminitis.

Types of Carbohydrates
Carbohydrates found in equine diets can be divided into two types: Structural andNon-structural. Structural carbohydrates are often referred to as fibre and arecritical in the equine diet. Non-structural carbohydrates (NSC) are sugars andstarches that are broken down by enzymes in the horse’s small intestine into simplesugars. These simple sugars are absorbed from the small intestine and circulate inthe blood as glucose. The hormone insulin removes glucose from the blood and storesit in the liver and muscle as glycogen, or when an excess amount of NSC is consumed,it is converted to fat and stored throughout the body. Common examples of non-structural carbohydrates in horse diets include cereal grains (oats, corn, barley,etc) and molasses. Research has shown that metabolic disorders such as Obesity,Insulin Resistance, Laminitis, Cushings, Tying-Up as well as behavioural excitabilityare associated with excess NSC (sugar and starch) and not with structural (fibre)carbohydrates in the diet. Expert nutritionists and veterinarians researching in thisfield have determined “low carb” to be less than 10% NSC.

Feeding Management
We must carefully manage pasture turnout and forage and grain intake in horses andponies that are at risk for developing laminitis or are currently affected. We alsounderstand that horses suffering from insulin resistance (IR) and/or Cushings as wellas horses and ponies with the ‘‘easy keeper,’’ phenotype that are often overweight orobese, and may be persistently hyperinsulinemic should also be managed carefully withregard to their carbohydrate intake.

The following points summarize current advice regarding strategies for avoiding highNSC intakes by horses and ponies at risk for pasture laminitis:
• Animals predisposed to laminitis should be denied access to grass pastures,particularly during the spring.
• At other times of the year, limit the amount of turnout time each day (e.g., 1–3hours) and turn animals out late at night (after 8:00pm) or early in the morning,removing them from pasture by midmorning at the latest (before 10:00am, because NSClevels are likely to be at their lowest late at night through early morning).
• Alternatively, limit the size of the available pasture by use of temporary fencingto create small paddocks or use a grazing muzzle.
• Do not turn horses out onto pasture that has been exposed to low temperatures inconjunction with bright sunlight, such as occurs in the autumn after a flush ofgrowth or on bright cool winter days, because cold temperatures reduce grass growth,resulting in the accumulation of NSC.

Animals denied access to pasture for most or all of the day, require provision ofalternative feedstuffs. Horses at maintenance require approximately 2.0% of theirbody weight as forage or forage plus supplement to meet daily nutrient requirements.Sweet feeds should not be fed and the feeding of other ‘‘treats,’’ such as carrotsand apples, should be discouraged. Lucerne hay or other legumes, such as clover, onaverage, have lower NSC content when compared with grass hay but have considerablyhigher calorie/energy content.

HYGAIN Solution
HYGAIN® Feeds also offers a forage-based low energy feed complete with vitamins andminerals: HYGAIN® ZERO®. HYGAIN® ZERO® is a unique Low Carb - Low GI feed for allhorses, with less than 1.5% starch, less than 5.5% non structural carbohydrates (NSC)and absolutely no grain or grain by-products. HYGAIN® ZERO® was developed to supportthe specialised dietary requirements of horses and ponies with conditions such asObesity, Insulin Resistance, Laminitis, Cushings, Tying-Up or Grain Intolerance. Theunique Low Carb – Low GI profile however is suitable for any equine requiring a lowsugar and starch diet.

Visit Hygain

See more horse feeding and nutrition articles in The Feed Room

Comment on this article using the Comment Function below. Discuss this article withother users on the Horse Forums.

Got News? Send your news stories and press releases to the HorseYard News Desk.