Thehorse.com - Full Article
by: Kristen M. Janicki, MS, PAS
September 02 2012, Article # 20576
Starch is a highly digestible energy form and can provide energy needed for exercise, growth, metabolism, and other equine life functions. However, when fed improperly, this nonstructural carbohydrate can be detrimental to your horse's health.
Most of the energy contained in grains, such as corn and oats, and a percentage of the energy from forage is starch. During digestion, starch is broken down primarily in the horse's small intestine by an enzyme called amylase. This process efficiently produces glucose, a type of simple sugar essential for fueling some bodily functions.
The amount of starch consumed at one time also affects the amount of starch digested in the small intestine. If starch is not digested in the small intestine (which occurs when large amounts of starches are fed at once), it passes through the digestive tract and is fermented in the large intestine. This fermentation process, while less efficient than digestion in the small intestine, also produces energy to keep the horse's body functioning...
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