Mother Nature gave horses the very best insulation available-their own thick winter coat. Under normal circumstances a horse starts to grow a thick winter coat when daylight decreases. His coat is all he needs to keep him warm. But human interference, body clipping or changing climates, can cause your horse to be unprepared for extreme weather. He may need a little extra help keeping warm.
Check your barn for drafts. You want to have good ventilation in your barn, but unnecessary drafts just stir up dust and can give your horse chills. Cold, strong winds combined with wet conditions pose the greatest danger to your horse's health in winter. When the wind tousles your horse's hair it takes away all the heat trapped by her thick winter coat. Wind can pull surface heat away from a horse's body quicker than your horse can generate more heat. When she's wet and the wind is blowing, its even harder for her to stay warm.
Bring your horse in at night and turn him out during the day when the sun is up and the temperature is a little warmer.
Provide horses living outside or being turned out during heavy, cold rains or snow with a simple three-sided, roofed shelter to provide them protection from the weather. Make sure the roof is angled away from the entrance and there is adequate drainage as muddy holes tend to develop in the front of run-in shelters as horses go in and out repeatedly. The shelter should be large enough for the horses in the pasture. If you have many horses, you may need to provide more than one shelter.
Feed your horse additional hay. Digestion generates more heat than any other body function. A horse typically requires 1 percent of his body weight in good quality roughage per day to function. Up this amount to help keep your horse warm as the weather becomes more severe.
Make sure your horse is getting enough grain. In the winter, your horse burns additional calories. Although you have upped his hay, it may not be enough to keep him warm.
Consider blanketing your horse if he is clipped, has recently been relocated from a warmer climate, does not deal well with cold or your area's weather is particularly frigid. Older horses or horses that have been ill may also require blanketing. Layer your horse's blankets adding and removing them as the weather changes.
If your horse is blanketed, remove it daily and check him over for any cuts, rubs or scratches.
For horses with heavy winter coats, be sure to check them over every few days for cuts and scrapes that may be hidden by their long hair. This is also a good time to check their body condition - long hair can make it hard to tell when a horse is losing weight.
Be sure your horse is getting enough water. When the water gets cold, some horses don't like to drink. A water tank heater can help keep the water warm enough so that horses will drink. If your horse still doesn't drink enough, you might want to feed soaked beet pulp or soaked alfalfa cubes.
If you ride throughout the winter, make sure to warm your horse up slowly and cool him out slowly and thoroughly before putting him away. If you ride during the winter, make sure to warm your horse's bit before putting it in his mouth.