by Cynthia McFarland

From the consumer's point of view, there are legitimate reasons for wanting a complete equine feed. Convenience of feeding and ease of storage are among the advantages. Yet the definition of a complete feed is often confusing.

"There are several complete feeds on the market available from a variety of feed manufacturers," said Larry Lawrence, Ph.D., a nutritionist at Kentucky Equine Research (KER) in Versailles, Kentucky. KER is an authority on equine nutrition and exercise physiology as a result of its consultation and research efforts.

"From a feed manufacturing perspective, a complete feed is a feed that can be fed alone with little supplemental pasture or hay, so the feed contains significant quantities of roughage," Lawrence explained.

This roughage can derive from different sources, some more desirable than others. Quality sources include dehydrated and ground alfalfa meal, soybean hulls (the thin, film-like skin on the bean), wheat middlings (a mixture of ground wheat and bran), beet pulp, or a combination of these sources.

Roughage sources that are high in indigestible fiber include oat hulls, peanut hulls, corn screenings, or ground corn cobs. If the feed contains significant amounts of such ingredients, it would not be a recommended complete feed. Corn screenings and peanut hulls can contain mycotoxins that can cause toxicity problems in horses.

Digestive needs

The basic concept of a complete feed in a bag raises issues that have nothing to do with providing the nutrients the horse needs. Equine nutritionists are quite capable of creating a complete feed that totally meets the horse's nutritional needs. The main problem is that forage in pellet or cube form does not satisfy the requirements of the horse's normal digestive process.

"A complete feed is a way to stretch your hay supply and reduce the amount of roughage you feed. But you can't completely eliminate roughage in a horse's diet or you get behavioral aberrations and digestive problems," said Gary Potter, Ph.D., of College Station, Texas. Potter conducted equine nutrition and physiology research and taught equine science, nutrition, and equine physiology courses at Texas A&M University for 35 years.

"In nature, a horse eats all the time, and the digestive system is designed to take in large volumes of bulky-type feeds. This presents a problem from a digestive point when you take everything, grind it up, reduce the volume, and put it in a pellet or cube," said Potter, who now manages Potter Enterprises, an international equine consulting business.

The horse's digestive system performs best when fed long-stemmed hay or grass. Chopped forage would be a second preference, while coarsely or finely ground or pelleted forage would be least preferable.

An obvious place for a high-roughage, complete bagged feed is in the ration of a geriatric horse.

"When horses get older and lose their teeth and can't chew well, complete feeds work well," Lawrence said. "Complete feeds are pelleted, and pellets are easy for horses to chew; when soaked in water, they break up into a mash very easily."

It is much easier to feed one product, and bagged feed takes up much less storage space than hay. Hay quality can vary dramatically and prices continue to rise, tempting some owners to think of ways to eliminate hay completely from the horse's diet.

The horse still needs some type of long forage in the form of hay or fresh grass on which to graze. A processed equine ration takes much less time for the horse to eat, which goes directly against nature's design. Forage in pellet or cube form does not satisfy the need for bulk in the gastrointestinal tract.

Without adequate roughage, the horse's digestive system cannot maintain normal function. When a horse is not eating continually, it eventually develops behavioral aberrations. This is one reason you find horses eating dirt or bedding and chewing on wood or other horses' manes and tails.

Some horse owners think they can feed poor-quality hay if they are providing a balanced concentrate that meets nutritional needs, but this is a fallacy. High-quality forage, whether grass or hay, is a vital part of the equine diet. Coarse, fibrous forage can lead to an accumulation of indigestible material in the gut and may result in impaction colic.

A bulky, high-fiber complete feed has fewer calories per pound compared with a typical grain-based feed, which means you will have to feed more of it.

"This isn't necessarily a bad thing, but you need to realize that a 50-pound bag of complete feed is not the same as a 50-pound bag of typical horse feed, such as sweet feed or a pelleted grain mix," Potter said.

Complete feeds contain roughage and are meant to be fed at amounts of approximately 15 to 20 pounds per day to make up for the hay or grass not being fed. Typical grain-based concentrate feeds are usually fed at amounts of five to eight pounds per day. You will have problems if you do not feed a complete feed at the recommended amounts because the horse will not be getting the essential nutrients his body needs.

"For the horse to receive all the vitamins and minerals provided by feed, the product must be fed according to manufacturer directions," Lawrence said.

The typical sweet feed containing mostly corn, oats, and barley will have a crude fiber of only 5% to 8%. By comparison, true complete feeds are much higher in crude fiber, usually ranging from 18% to 22%.

"Even with that much fiber in the feed, it is best if some long-stemmed hay or at least cubed hay that has been chopped no smaller that one inch in length is included in the ration each day," Lawrence said. "This physical form helps keep the hindgut functioning properly. The hindgut is designed to digest forage by bacterial fermentation."

Fighting nature

"The way we manage horses in most ways is very contrary to their nature," Potter said. "They are not designed to be confined, and they're not designed to be fed just two or even three meals a day. The digestive physiology and the horse's nature are such that the horse needs to be eating almost all the time for its systems to function normally.

"A fundamental issue with the concept of complete feed is that any time you process roughage and artificially grind it up and reduce the particle size, the horse doesn't have to chew it as much."

The equine digestive system is made to chew a large volume of roughage over the course of many hours each day. The saliva produced by the horse is directly related to how much it chews, and it is meant to chew a lot. If the horse is fed a refined, condensed ration, it does not have to chew as much. This means it will be swallowing that feed with less saliva, and this decrease in saliva can lead to digestive problems.

"I tell my race-stable clients if there is any way you can take the horse out to graze an hour or two a day, you'll be surprised at the results you get," Potter said. "If horses can graze every day, they just don't have many digestive problems. I'm convinced one of the reasons horses in training have gastric ulcers has nothing to do with anxiety but everything to do with the fact that they're taken out of a normal habitat from a digestive point of view."

Ration balancers

Ration balancers, or concentrated supplements, are popular with many horse owners. The labels on such products instruct you to feed different amounts, depending on the age, use, and condition of the horse. For example, a lactating mare would require a greater portion than a mature, idle horse.

"These are pellets that have high concentrations of protein, minerals, and vitamins," said Lawrence, noting that balancer pellets are usually fed at a rate of one to two pounds per day. "They are designed to be added to typical cereal grains like oats and barley to balance out the deficiencies the grains have and help meet the requirements of the essential nutrients."

Lawrence said ration balancers are useful in a variety of feeding programs, especially when you do not need to feed for extra energy.

"When broodmares are too fat in the first two trimesters with a condition score of eight to nine on a scale of one to nine, a balancer pellet insures that essential nutrients are included without having to feed excess energy," Lawrence said. "When horses are stall-bound and you want to decrease energy because of an injury, balancer pellets are very useful."

When young horses are growing too rapidly and are diagnosed with some form of developmental orthopedic disease, an abundance of energy is usually the problem. You do not want to compromise growth by eliminating the essential calcium and phosphorus and other important minerals and vitamins, so a ration balancer works well in this situation.

Potter said concentrated supplements are a very valid concept simply because horses do not require the same amounts and levels of nutrients at the same time throughout their lives. However, the drawback of such ration balancers is that they easily can be overfed.

"Concentrated supplements can certainly be abused," he said. "People think that if a little does a good job, then a lot will do a better job."

Potter compared adding supplements to a horse's ration to filling a glass with water. Once the glass is full, it will overflow and spill over. The same principle applies when adding supplements to the horse's diet. If you add more than the horse needs, its body is forced to excrete it. This is not only a waste of money, but it also can present a challenge to the horse's body because it must rid itself of unnecessary vitamins and minerals.

Not all vitamins are water-soluble and able to be excreted quickly. By greatly overfeeding fat-soluble vitamins such as A and D, you run the risk of hitting toxic levels and can severely compromise the horse's health. For example, excess vitamin D can interfere with normal bone growth in the young horse, and feeding high levels of vitamin A can result in brittle, fragile bones.

Applying research

Potter is concerned that many horse owners fail to apply the vast amount of research and information available on equine nutrition. This "disconnect," as he calls it, between nutrition information and its actual application is not found to the same extent in other areas of livestock nutrition and feeding.

"Other segments of the livestock industry—beef and dairy cattle, poultry, and swine—are right on the cutting edge and doing a better job of meeting the nutritional needs of their animals," Potter said. "The poultry industry in particular will implement new research technology almost instantaneously. There's a wealth of equine nutrition information available, but not nearly enough of this is applied on a routine basis."

As a result, many horses end up with improper bone growth and development, as well as digestive disturbances.

Many racing stables feed a combination of oats and sweet feed. Oats are a good source of energy, but they are not balanced in calcium and phosphorus; they are also very low in other minerals and vitamins. A ration of equal parts of balanced sweet feed and oats dilutes the calcium, trace minerals, and vitamins in the balanced feed. Horses on such a ration would need supplementation just to meet their daily nutritional requirements, which is going back to where you started.

In addition to oats and sweet feed, many racing stables feed wheat bran, vitamin supplements, electrolytes, and other supplements. Often, the person in charge of feeding horses ends up unintentionally unbalancing the horse's ration by adding these other components.

"Taking a well-balanced, fortified feed and cutting it with a grain source such as plain oats is a common mistake," Lawrence said. "Commercial feeds are fortified with essential nutrients so that requirements are met at a set level of intake. When you add unfortified oats that have not been supplemented with calcium, phosphorus, trace minerals, and vitamins you have unbalanced the ration.

"While you still may meet the energy requirement and the horses may look fine, you may be shorting the horse on some essential nutrients, such as selenium or vitamin E. In addition, you may be creating an inverted calcium-to-phosphorus ratio, which can lead to problems with calcium absorption."

For those horse owners who prefer to feed plain oats, Lawrence suggested adding ration-balancer pellets to ensure the horses are getting the essential nutrients they need in the right amounts and correct ratios.

"I deal with racehorses every day," said Potter, a lifelong horse owner. "These magnificent creatures run their hearts out at the racetrack, in many cases in spite of the way they're fed, not because of the way they're fed. There is a lot of room to apply research technology and information on nutrition and training of the athletic horse. There's a big gap between what's available and what's applied. This is almost a crusade with me."

Horse owners often base feeding programs on tradition rather than on what the horse actually needs.

"Let's say someone is feeding just oats and straight timothy, and their horse is winning. The reason the horse is successful has nothing to do with how he's fed, but rather how good a horse he is," Potter said. "Some horses just defy imagination. They're tough and sound and outlast other horses. But that owner is hard-pressed to understand that his horse's accomplishments have nothing to do with how he's being fed. You can put ground up bat wings in a horse's feed and if he wins a graded race, everyone wants to know where to get them, but there's a big disconnect between cause and effect."

"Feeding Thoroughbreds has historically been more of an art than a science," Lawrence said. "That is changing, and science has a lot to offer to Thoroughbred trainers and managers."

Cynthia McFarland is a Florida-based freelance writer