In its natural state, corn starch is not particularly digestible in the equine small intestine. However, both steam flaking and extrusion can increase corn’s digestibility. | Photo: Photos.com

Q. A friend recently recommended that I switch my horse to a different commercial feed because his current one contains corn. She said horses cannot digest corn so to look for a product without it. Is this true?

A. Corn has been fed to horses for decades in a number of forms, often either cracked or steam flaked. Traditionally it’s been a popular feed ingredient because of its easy availability, low cost, and high calorie content (about 1.76 Mcals per pound). Steam-flaked corn was often combined with oats and barley, then coated with molasses to make a feed known as COB, which some owners still feed. Modern corn processing includes extrusion, and it’s sometimes ground so it can be mixed with other ingredients to form pellets.

Today, however, corn is a less common horse feed ingredient for a number of reasons, one being that a lot of corn is diverted away from livestock feed in favor of use for ethanol production. Another is that, overall, horse feeds today typically have lower starch contents than their predecessors. This is because research has shed light on the negative implications of feeding horses too much starch, especially those used in disciplines where high-starch diets are not necessary