With the first arctic cold snap of the year impacting the Midwest, its a good time to review winter energy needs. The horse requires additional dietary energy in order to maintain its body temperature and condition. For every degree below 18°F the horse requires an additional 1% energy in their diet. For example, if a 1,000 lb horse needed 16 pounds of good-quality hay each day when the temperature was above 18° F, its requirement would be increased by about 2.5 pounds (to 18.5 pounds daily) if the temperature dropped to 0° F.