The large colon is 10 to 12 feet long and has a capacity of about 85 quarts. The small colon is 10 to 12 feet long and has a capacity of 15 quarts. It becomes immediately apparent from the foregoing information that the horse's system is indeed designed to handle forage on a continuous basis. In other words, tossing hay once a day isn't the best feeding practice during the winter or any other time there isn't adequate grazing. There is another problem with that scenario, one that can cause serious stress at feeding time.
Horses are herd animals which live within a structured and ongoing pecking order.
There is a dominant horse in every group. All the others will step aside when that horse approaches to eat or drink. However, the pecking order doesn't stop there. It continues on down the line until all horses in the group are accounted for. What this means is that horses which are very low in the pecking order might be kept away from the food supply until it is diminished or even exhausted.