The next few days will bring freezing weather to many parts of the country, and with that comes the need for extra care and attention for horses, donkeys, ponies, mules, and any other outdoor animals.
As the temperatures decrease, a horse's feed requirements increase. Allowing horses free choice to good quality forage (hay) is the surest way to ensure that they consume enough energy, and the process of digesting forage will actually produce heat. Horses will typically consume 2 to 2.5% of their body weight in forage each day; that would be 25 pounds per day for a 1,000 pound horse. Winter pasture alone will not provide enough forage to sustain a horse and, therefore, must be supplemented with hay and/or grain.
The growing season some parts of the nation had last year produced overly stemmy or fibrous hay with a lower digestibility. As a result, making certain that horses are supplemented with grain when fed lower quality hay will help them maintain body weight and condition, a key factor in withstanding cold temperatures.
Constant access to clean, fresh water at 35 to 50°F is an absolute necessity to keeping horses healthy. This can be achieved via heated tanks or buckets, or by filling a tank, letting it freeze, cutting an access hole in the frozen surface, and then always filling the tank to below the level of the hole from that point on. This provides a self-insulating function and will typically keep the water below from freezing. Regardless of the method you choose, it's important to check tanks frequently to ensure your horse's water remains free of ice.
Source: TheHorse