Detrimental Effects of Feeding High Sugar / High Starch Feeds
Typically, grain and concentrate type of rations are higher in sugar and starch than forages. When horses are on a ration or diet that has a high sugar and starch content, it can have dramatic effects on the digestive physiology such as:
There is less chewing, less saliva produced, more acidic contents in the stomach – possibly more gas or development of gastric ulcers.
The ingested feed moves faster through the small intestine - more sugar/starch substrate enters the hindgut upon which abnormal bacteria feed and proliferate.
The bacteria that feed on sugar and starch grow rapidly causing normal gut bacteria to die, bringing about inflammatory changes in the gut, and the dying bacteria give off endotoxins that are absorbed into the bloodstream. This can potentially lead to laminitis. These changes can result in abdominal pain, inflammatory disease, and digestive upset. Thus colic is another possible consequence.
The sugar and starch is absorbed rapidly from the small intestine, resulting in an elevated blood glucose level and a subsequent increase in insulin in the blood.
Therefore, three serious problems that occur from ingestion of high-sugar/high starch feeds are: laminitis, colic and insulin resistance.