HORSES & THEIR NEEDS

Every horse is different and has different needs. It is nutritionally impossible to make one feed that can be used as a sole source of feed for all horses at all stages of their life cycles.

Horses need nutrients for maintenance, growth, fattening, reproduction and work. Unlike most animals, the work is usually irregular and often very strenuous. These characteristics create a particular stress on the animal, and make the job of feeding, according to nutritive needs, very difficult.

The digestive system of a mature horse is over 100 feet long, and being that long, it is subject to twisting problems. By looking at the attached diagram, it is easy to see changes in diameter in many places - enlarging at the stomach, narrowing at the small intestine, enlarging at the cecum and narrowing in the colon.

Grain and hay when fed to a horse takes about 45 minutes to reach the ceacum, and about 70 hours to reach the feces. If too much feed enters the digestive system at one time, it is easy to overpower the horse's small intestine. When that happens, feed which should be digested in the small intestine is carried right through to the large intestine where it will ferment.

One by-product of fermentation is lactic acid which builds up in the hind gut throwing off the acid:base balance and can cause a deadly colic. In less severe cases, fermentation in the large intestine can cause laminitis. To avoid overloading the digestive system, experts recommend that larger amounts of feed by spread out over several feedings. Feeding three times daily is certainly safer than twice when large quantities of grain or hay need to be consumed to meet the needs of performance horses.

The horse's digestive tract differs anatomically and physiologically from that of the cow (ruminant) as follows:

1. It is smaller. With the result that horses cannot eat as much roughage as cattle. Also, it functions best at two thirds capacity.
2. Without feed the horse's stomach will empty completely in 24 hours. It takes 72 hours for the cow's stomach to empty completely.
3. The horse has a simple stomach, while the cow has a compound, four compartment system.
4. There is a very little microbial action in the stomach of the horse, but much the same action in the first compartment (rumen) of a cow.
5. The primary seats of microbial activity in ruminants and horses occupy different locations in the digestive tract in relation to the small intestine, the main site of nutrient absorption. In cattle the rumen precedes the small intestine while in the horse, the cecum follows it. As a result, the efficiency of absorption of nutrients synthesized by the microorganisms is significantly lower in the horse than in a ruminant.

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