Heart and respiration rates of fat horses take longer to return to normal, which indicates they aren't properly conditioned. Overweight, non-conditioned horses fatigue quicker and are more likely to have serious injuries. A conditioning and training program should reduce the body fat of horses, while getting their cardiovascular, muscular, and skeletal systems ready for performance. Proper feeding is important to keep performance horses cool in the summer months. Oats isn't a cool grain.
Corn is a cooler grain to feed in summer than oats.
It takes about 30 days for horses to adapt to fat-added rations. Feed a fine, high-quality hay, too. Coarser hays produce more internal body heat. For intense performance, don't limit hay below one percent of body weight. Beet pulp or soybean hulls can be fed as highly fermentable fiber sources.