Utah State University Extension
Concentrate (grain) should be considered only as supplements to good quality hay. In general, a mature horse does not require the energy provided by concentrate-type feeds (grains/sweet feeds, pelleted feed, etc.) unless the horse is used for more than light work or in production, such as a lactating mare or a breeding stallion. Too many times horses are overfed rather than underfed. This fact sheet will help horse owners understand the digestive process and the general feeding requirements, including different grains and mixed grains, for their horses.
Hoopes, Karl; Evans, Patricia; and McKendrick, Scott, "Equine Nutrition: Concentrates" (2020). All Current Publications. Paper 114.