Corn and Maize: History from the Horse’s Mouth

Corn, a staple of many equine diets, has the scientific name Zea mays. The genus Zea indicates that corn is essentially a type of grass. The species name, mays, is one of five groups in the genus and is further divided into four subspecies. Zea mays subsp. mays, or what we know as corn, is the only domesticated strain within the genus.

Terminology for this grain, which is actually a highly developed grass seed, varies from country to country. In some English-speaking regions, the yellow kernels are referred to as maize, which distinguishes it from “corn,” a general term that can mean any type of grain. “Maize” and “mays” both come from maíz, the Spanish word for corn. This is based on mahiz, which was the name used for the crop by the Taino tribe in the Caribbean area where corn was cultivated from prehistoric times. When Spanish explorers came to that region in the late fifteenth century, corn was being grown as a food and also as a trade commodity. The explorers took the grain back to Europe and found that it grew easily in a wide range of climates. Today, corn is grown in many countries, and is the most widely grown grain crop throughout North and South America.

Very early corn plants produced only a single inch-long ear per plant, but prehistoric growers selectively improved the crop to produce larger and more abundant seedheads. The corn was harvested and was often soaked in limewater to soften the kernels and loosen them from the cobs. This process, known as nixtamalization, reduced mycotoxins and improved flavor and aroma.

Corn can be fed to horses as whole, cracked, crushed, ground, or steam-flaked kernels. It can be used alone or as part of a grain mix. Corn starch is not digested as well as oat starch, and if a large amount is fed, there is a danger that some of the undigested starch will flow into the hindgut and trigger digestive upsets. Processing corn improves its digestibility in horses, decreasing the risk. Owners should avoid problems by not feeding large meals of corn to horses.