You must look at each horse s situation as an individual. The impact of cold weather is much less on horses that are dry and out of the wind, while larger adjustments must be made for horses exposed to the elements. Even a simple windbreak helps. A dry winter coat stops most of the body heat loss. A layer of body fat serves as insulation and can also be metabolized as a heat source.
Cold weather causes no significant increase in protein requirements.
Whether your horse is growing, lactating, working, or inactive, his or her protein requirement will be the same as in warm weather. Unlike protein, however, energy requirements do go up as the temperature falls. This is due to the body s need to metabolize carbohydrates, and to a much lesser degree fats, to maintain constant body temperature. Most horses see a decrease in activity levels during cold weather. If these horses are allowed free choice roughage, they will take care of their own needs, up to a point, by eating more.