As I was reviewing the feed program for one of my client’s lesson horses, she mentioned ordering corn to add to the feed for the winter. She felt this would provide the horses extra warmth in the cold weather. This is a common winter practice with many farms, and I explained to my client that she was correct to increase the horse’s caloric intake with falling temperatures. There is a much better alternative to corn, though – it is much more efficient and effective to increase the forage portion of the diet to help create internal heat in the winter. This is due to the fermentation process the forage goes through in the hindgut, and the heat that process gives off.
The term “critical temperature” is used determine at what temperature a horses nutritional requirements change to maintain normal body temperature. I use the temperature of 40 F as a benchmark for calculating winter diets. In essence for every 1 degree below critical temperature, I increase the horse’s caloric intake by 1%. So, if my 1000 pound horse were receiving 18.6 Mcal (18,600 calories per day), I would increase his diet by 1860 calories when the temperature goes to 30 degrees (10 X 186). If my hay has tested at 10Mcal (1000 calories) per pound, an additional 2 pounds of hay will help my horse maintain his body condition at that temperature.
I also encourage my clients to feed a well fortified concentrate during the winter months. The lack of fresh pasture, limited sunlight hours, and often diminished hay quality require better fortification. Make sure your horse feed provides adequate levels of vitamin A, D and E. Feeds offering probiotics and prebiotics, as well as biotin are also encouraged. If you are feed a grass hay or alfalfa hay, make sure your calcium and phosphorus levels are also balanced accordingly in your feed.
Water consumption is imperative during winter months. Make sure that the buckets are free from ice and frozen debris. In the winter horses will consume 10 to 12 gallons of water per day. Ideally the water temperature should be at 50-65 F to encourage drinking.
Examine your horses body condition score monthly during the winter to maintain a healthy horse!