Dietary Needs

There’s a well known saying for humans: “we are what we eat”. Well, we can safely say that such adage may also apply to horses.
The proper nutrition, coupled with the right conditioning for the discipline, results in a healthy horse for the stable owner. But if there’s something lacking in the diet, then a horse can’t function properly and both physical and behavioral problems start to arise.
The food which we feed to horses needs to meet seven fundamental requirements. Five of these requirements include:
Energy − It needs to provide sufficient energy (calories) to meet the requirements of the horse. If the weather becomes colder or the horse is used more actively, the amount of food will need to be increased accordingly. Likewise, as winter turns into summer or if the horse is less active, the amount of food should be decreased.
Vitamins and minerals − Aside from energy, horse feed needs to provide a variety of essential minerals and vitamins, in the required quantities.
Bulk and high fiber content − The equine digestive system has evolved to process grass, which is high in fiber and bulk. Food which is concentrated (e.g. grain) may provide the required energy and minerals. Unfortunately, it lacks the bulk which the digestive system needs, which greatly increases the risk of ulcers and other diseases. Studies have shown that horses fed a diet high in grain or other concentrated foods have 50% to 90% of these horses with ulcers.
Readily digestible − Food which is poorly digested provides limited food value and can cause serious illnesses (e.g. impaction colic). This is a particular problem for the older horse, where dental wear reduces his ability to chew food and aging has reduced his ability to digest certain foods. In addition, horses may eat unsuitable items (e.g. straw) which do provide food value but due to difficulty in digestion could also result in problems.
Safety − Almost any food, given in incorrect amounts or fashion, can result in serious health issues.
To understand the other two fundamental requirements, it helps to first understand the normal eating patterns of horses. Horses have evolved as foragers, which means that they eat for a little while in one place, then move on in search of better food (e.g. more tender or nutritious) and eat somewhere else. One often sees this behavior when the horse is in a large pasture, where they frequently move from place to place.
The reason for this behavior is that they evolved in a landscape where the quality of food was variable (as opposed to the largely uniform grassland which we create in our pastures) so they needed to spend most of their time moving and eating, usually up to 18 hours per day. This has resulted in two dietary requirements:
Continuous Feeding − Although a horse does not eat constantly (e.g. it spends part of its time moving about and other activities), it needs to eat frequently. It needs a minimum of 2-3 meals each day to keep its digestive system healthy, but more frequent eating is preferable. Many small meals are better than a few large meals. This is one of the reasons that horses which graze on pasture during the day are generally healthier than horses which have their food (e.g. hay or grain) given to them once or twice a day.
Stimulation − A horse’s main stimulation and occupation comes from looking for food and eating (typical foraging activity). Restricting it to short and infrequent feedings will result in a bored and unhappy horse, which is likely to develop stress related behaviors such as cribbing or repetitive movements.
Based on these fundamental requirements, grass and hay are the recommended feed for horses especially to discourage cribbing based on the following:
• Grass is the most natural food for horses, as it is what they have evolved to eat. In general, horses will tend to be healthier on a diet which consists mainly of grass than on any other type of food.
• Hay is the second most natural food, being rather close to the dried grass which they might find after a hot and dry summer or dried winter grass. It is less nutritious than fresh grass but good quality hay is a useful alternative when there’s not enough fresh grass.
• One of the major risks with grass is that grass which is overly rich in carbohydrates (e.g. spring grass) or nitrates (e.g. fertilized field) can cause “laminitis” or “founder”. Laminitis is one of the most common causes of lameness and disability of horses and ponies in this country. Excessively rich hay may have the same risk, but since hay is made at a time of year when the grass is naturally less rich, this is much less likely.
• Grain and musli, when purchased in the form of commercial horse feeds, are high-energy foods which are easily digested. Musli is made from a selection of crushed grains and may have minerals or vitamins added, as well as sugar, fiber and filler.
• These products are fed to horses used for sport, not only for the quick energy which they provide, but also because they result in a much trimmer body. Hay and grass are not only bulky, but also result in additional bulk in terms of digestive gases and food in various stages of digestion or elimination. Consequently, for activities such as racing or jumping, the diet of competition horses is normally high in grain or musli.
• The advantages of these types of feed include convenience, potential cost savings, and a slim torso for competition. In addition, horses which are old, sick or under-nourished can benefit from having their normal diets supplemented by these high-energy foods, especially during the winter when they require additional energy to keep warm.
• There are also a number of disadvantages. These energy-dense foods do not offer the bulk, fiber or mental stimulation required by horses. If the foods are fed as a supplement to the traditional diet of hay and straw this is not an issue. However, when such foods from the bulk of the horse’s diet, the lack of bulk and fiber can result in various digestive issues (ulcers are common in such cases) and the lack of stimulation can result in stress and the development of undesirable habits (such as cribbing or repetitive movements).
• The best results, both in cribbers and pre-cribbers, were experienced in horses on plain feed: corn, oats and barley. The use of sweet feed (molasses) or any treats with either refined or natural sugars tended to exacerbate cribbing and pre-cribbing symptoms. Horses in remission from cribbing would exhibit cribbing tendencies after eating sweet feeds or treats.