Nutrition Part 2 — From Foal to the Racetrack

by Dr. Stephen Duren

Performance Horse Nutrition

Wherever Thoroughbreds are grown, the goal in raising these horses is simple – produce sound, athletic horses. One factor that cannot be ignored in this quest is nutrition. Few topics stir more controversy than properly feeding horses. When do we begin feeding mares to help ensure sound foals? What influence does nutrition have on soundness of yearlings and ultimately future race performance? Do we feed Thoroughbreds in Washington or Kentucky the same way we feed in Japan, Australia, Canada and Europe?

Nutrition does not need to be a confusing topic. Instead, we must understand some basic principles and make sure our horses have their nutritional needs satisfied at all stages of life, from conception to the racetrack. In part one of this two-part series on “Nutrition – From Conception to Lactation,” we discussed feeding the broodmare. In part two we will concentrate on feeding young, growing horses.

The Nursing Foal

A carefully planned mating, an 11-month wait and the foal has finally arrived. Is this foal destined to win the Kentucky Derby (G1), the Longacres Mile (G3) or some other graded stakes? Before a foal can achieve racing success, it must first grow a sound skeleton and healthy musculature. Nutrition is fundamental for growth. In fact, nutrition mistakes made early in a horse’s life have a profound negative impact on its health and soundness for the rest of its life.

A healthy foal will grow rapidly, gaining in height, weight and strength almost before your eyes. From birth to age two years, a young horse can achieve 90 percent or more of its full adult size. To support this rapid weight gain, a young growing horse must be fed correctly. The critical nutrients for growth are energy, protein (amino acids), minerals and vitamins. Nutrition imbalances, too much or too little nutrient, have been recognized as one potential cause of growth anomalies in young horses.

Nursing foals will meet their nutritional requirements in their first 60 days of life with mare’s milk, good quality pasture and small amounts of grain stolen from the mare’s feed bin. The primary reason a foal can satisfy its need for trace minerals early in life is because the mare has stored these minerals in the foal’s liver during pregnancy. This is a key reason that farms such as El Dorado Farms are diligent at feeding pregnant mares correctly.

At 60 days of age, the foal’s liver stores of vital trace minerals is waning and the mare’s milk production typically has reached its peak and will begin to decline. The foal’s nutrient requirements will continue to increase creating a nutrient gap between the nutrients provided in milk and the foal’s nutrient requirements. To fill this nutrient gap, a foal will need to be fed supplement feed often referred to as “creep” feed. If a foal is thin, usually due to poor milk production of the mare, a foal will need to receive supplemental feed prior to 60 days of age. The supplemental (creep) feed must provide the essential nutrients required for foal growth. A feed specifically designed for feeding foals, is a must. Perennial leading breeder El Dorado Farms not only utilizes a feed specifically formulated for growing horses, but further ensures that feed (LMF Development) balances the unique hays and pastures in the Pacific Northwest.

Other “rules” for providing supplemental feed to a nursing foal include:

1. Use a feeder or feeding system designed to prevent the mare from eating the foal’s feed.

2. Place the feeder at a convenient height for the foal to consume feed.

3. Increase the amount of creep feed gradually until the foal is eating approximately one percent of its body weight per day.

4. Make sure the supplemental feed is fresh daily and that the foal is consuming it adequately.

The Weanling

Generally the growth rate of the foal decreases immediately after weaning. To minimize this “post weaning slump,” it is essential that foals are eating supplemental feed prior to weaning. Foals that are not accustom to eating their own feed will lose weight and then experience excessive weight gain that may cause bone abnormalities and long-lasting skeletal problems.

The weanling diet should be a combination of good quality forage and a well-fortified grain concentrate.

First, weanlings should have access to all the good quality hay and/or pasture they will consume. The hays grown in the Western United States are typically of exceptional quality and work extremely well for growing horses. Alfalfa, mixed grass plus alfalfa and high quality grass hay are all acceptable forages for growing horses. El Dorado Farms utilizes high quality alfalfa hay to ensure the weanlings consume adequate amounts of hay. The weanlings should also be allowed all the voluntary exercise they want. Research has shown that exercise strengthens bone, increases cortical thickness and makes for a more durable future athlete. This exercise is easily accomplished when weanlings are turned out and they are able to run and play with herd mates.

Second, weanlings also should be fed a fortified grain concentrate designed for a growing horse. El Dorado Farms utilizes the same grain (LMF Development) that was introduced to the nursing foals. Selection of the correct feed is critical since the nutrients in feed will help to form and develop the skeleton. Selection of a marginal or poorly fortified feed will result in slow growth rates and unsoundness that appears when the horses enter training. Weanlings should be fed fortified grain according to desired body condition and rate of grain. In general, weanlings will consume one pound of grain per month of age up to a maximum of six to seven pounds per weanling per day. It is important not to feed weanlings too much grain. If you feed them excessive levels of grain, they will grow more rapidly and this rapid growth may harm skeletal and tendon development. Therefore, adjust feed intake to avoid overfeeding.

The Yearling

In January of the yearling year it is time to begin to make plans for its future. Most Thoroughbreds are intended to become racehorses, but the path to the race track can be different with each of them. For example, some yearlings will be prepared for public auction while others will be raced by their current owners and not experience the pressure of public auction.

A yearling that is to be sold will need to be fed slightly different than a non-sales horse. Yearlings that will go to the sales will need to look their best in August and September. For a yearling to be well-grown and in adequate body condition for the sale usually requires more feed. Rather than wait and make drastic feed changes during the last 60 days prior to a sale, it is easier and safer to make gradual feed changes several months prior to the sale.

A yearling that is not destined for public auction can be kept in a body condition in which you can see the faint outline of ribs. They can be fed five-to-eight pounds per day of a well-fortified grain, such as LMF Development. Early in the yearling year, pasture will not be available and yearlings should be offered free-access to good quality hay. If yearlings are not kept on a steady growth curve, or you allow growth to slow or stop during the winter, the yearling will experience rapid growth in the spring which may result in bone problems.

Yearlings that are selected for public auction will also need to receive free-access to good quality forage. These yearlings will be maintained in a slightly higher body condition, no ribs showing, to facilitate growth and development. The amount of grain necessary to accomplish this goal is typically six to eight pounds per yearling per day. Starting approximately 90 days prior to the sale the yearlings will begin the formal preparation process. This usually involves more confinement in stalls, forced exercise on a mechanical walker or round pen and daily grooming. To meet the nutrient requirements for these horses, a higher fat grain is typically provided. Feeds with as much as 12 percent fat (LMF Gold) are highly palatable and help facilitate weight gain and enhance coat condition. These feeds are typically fed at six to ten pounds per yearling per day, depending on body condition and amount of exercise.

The Long Yearling

This is a critical time for the success of the future racehorse. At this time most of the horses are beginning the initial stages of breaking and training. It is common for yearlings during the breaking process to only be fed small amounts, or even no grain. This is done in an attempt to quiet the yearlings, making them easier to handle. This practice is the equivalent of starving them to submission. It is acceptable to feed less grain, as long as it is highly fortified with vitamins and minerals. If no grain is provided or if the grain is not properly fortified, the horses will not get the necessary nutrients to repair muscle and bone that is both growing and remodeling during the training process.

A product that works well in this situation is a low intake (1 lb/yearling/day) pelleted supplement, such as LMF Super Supplement, that provides essential protein along with critical minerals and vitamins to repair tissues. These vitamin/mineral supplements can be fed with varying amounts of oats, depending on the body condition of the yearling and the behavior of the yearling.

It is also important to provide long yearlings with good quality hay. During the breaking process and the initial stages of training is important to provide at minimum of five pounds of alfalfa per long yearling per day, along with free-choice grass hay. The alfalfa will provide essential protein and calcium to repair bones, develop muscle and help alleviate gastric ulcers.

Once long yearlings are cantering and doing some track work they can be gradually switched to a typical race diet. These diets include textured (sweet) feeds fortified specifically for racehorses. These feeds contain between 12 and 14 percent protein along with all the vitamins and minerals needed by racehorses.

It is important to follow label directions on these feeds to ensure these athletes are getting everything they need. A common mistake is to feed oats plus a small amount of sweet feed. In this situation, the oats do not contain added vitamins and minerals and the sweet feed is being fed at levels far below the manufacturer’s guidelines. This will result in a diet that does not provide adequate nutrition. Horses being fed these diets will be predisposed to both muscle and bone problems. A simple remedy for the problem is to simply make sure you are feeding the proper amount of fortified sweet feed and then a small amount of oats can be added to provide additional calories if necessary.

So there you have it. Nutrition explained in a two-part series that will ensure your mares and young, growing horses are fed properly. The nutrition program outlined in these articles has proven successful throughout the world and the program has been adapted and utilized by Washington State three-time leading breeder El Dorado Farms.

As El Dorado proprietor Nina Hagen (with husband Ron) states, “There is nothing better than seeing smiles in the winner’s circle. It’s really so simple. It’s all about balance and making the right choices.”

Stephen E. Duren, MS, PhD, PAS, a native of Soda Springs, Idaho, completed his Bachelor of Science in Animal Sciences at the University of Idaho. Duren earned a Master of Science and a Doctor of Philosophy in Equine Nutrition and Exercise Physiology from the University of Kentucky. Duren is recognized by the American Registry of Professional Animal Scientists as a member in good standing. He is also a member of the Equine Science Society (ESS) where he served as a board of directors’ member. Duren’s professional experience includes working as a technical services equine nutritionist for McCauley Brothers, Inc., an equine only feed manufacturer in Central Kentucky. In that role he was a consulting nutritionist for Adena Springs Farm, Darby Dan Farm, Three Chimneys Farm and Gainesway. Duren then worked as a consulting equine nutritionist for Kentucky Equine Research. This opportunity gave Duren his first international experience working with feed manufacturers in Europe, Australia and Canada. He was also responsible for large domestic clients, including Hallway Feeds and Pennfield Feeds. Duren has now formed Performance Horse Nutrition LLC, in which he consults with feed manufacturers and horse owners throughout the world. Some of the feed manufacturers that Duren consults with include LMF Feeds and Poulin Grain in the United States and Otter Co-op in Canada, Duren has also consulted directly with large horse farms, including Shadai Farm in Japan, Golden Eagle Farm in California, and Darley – Japan. Duren is a co-author of The Concise Guide to Nutrition in the Horse and is the author of  The 101 Most Frequently Asked Horse Nutrition Questions.