Keep them tethered tightly to your side if the route to the yard is icy. A bad slip can cause a ruptured disc, broken leg or other major injury. If you live near a pond or lake, thin ice is as much a risk to pets as to people If you live near a pond or lake, don't allow your pets or livestock to run loose without some thought on your part. They may head for thin ice and fall through if they are not familiar with icy ponds. It is very difficult to escape these watery graves and equally challenging for you to reach the site safely.
Nutrition is a particularly important concern.
Outdoor pets require more calories in the winter to generate energy to ward off the cold. As a result, add 10 to 15 percent more to its daily diet to allow it to meet those needs. Another way to meet cold weather calorie requirements is by adding some fats to their regular ration. Be careful though, fats can lead to diarrhea and dehydration if too much is added. Cold weather alone won't make healthy horses ill.