The first year of your foal’s life is the most crucial time to ensure that he’s on a good nutrition program. Consider weaning later, too, since his dam’s milk is the most nutritious and highly digestible food source he could have.

The first year of your foal’s life is the most critical stage for getting the correct nutrition. Essentially, you’re building the foundation for a lifetime of good health.

Weanlings and lactating mares have the highest mineral requirements of all horses, and your weanling’s need for protein is even higher. Pregnant and lactating mares will break down their own body stores of minerals and protein if need be, but your weanling is entirely dependent on diet to supply the nutrients needed.

Tales of Old
For many years in the past, we were told that weanlings didn’t have a well-developed capacity to process plant materials like grass or hay. But how could this be since we know now that the young feral horse eats nothing but grass and plants?

In nature, a feral foal will nurse its dam for as long as 12 months, and sometimes longer if it’s a filly. They don’t have any fancy feed from a bag, just grass and whatever else they choose to munch on. They do just fine. So, is there a lesson to be learned here?

Part of the answer to this question has to do with when we wean foals. Common practice is to wean a foal at 4 to 6 months of age. And it’s proving to be true that this is too early. Depriving a 4- to 6-month-old foal of its dam’s milk is taking away the most nutritious and highly digestible food source available. Unless there’s a pressing need to wean your foal at this young age—such as a crisis with the dam’s health—it’s far better to let the weaning process take a natural course.

Another explanation for the belief that young horses couldn’t ferment hay or grass well was the way they were managed before weaning. Heavy grain creep feeding was the rule of the day in years past. This led to populations of organisms in a foal’s bowel that were geared to breaking down and fermenting grain, not grasses. Grain lowers the pH of the large intestine (making it acidic), which is not a favorable environment for fermenting fiber. In short, it was true that they didn’t use grass well—but this wasn’t because of their age or development.

Does this mean you can leave your weanlings to fend for themselves in your pasture or just throw them hay? No. Because the domesticated horse’s diet can’t come even close to duplicating the variety of different plants a wild horse consumes in the course of traveling 25+ miles a day, the likelihood of imbalances and deficiencies is extremely high.

Building the Diet
To build your weanling’s diet, start with the highest quality hay you can find, or well maintained pasture. Work with an equine nutritionist or veterinarian with a special interest in nutrition. The forage portion of the diet should be analyzed to determine protein and mineral levels. If this is not possible because it changes too often, regional averages can be used. Your professional will know where to get this information.

The next step is to add a protein and mineral supplement that complements the forage well and corrects the deficiencies and imbalances. If you’re lucky, you’ll be able to find a commercially available supplement, usually in pelleted form, that can get the job done. Getting what you need by combining products with different profiles is also possible, or you can have a mix made up for you customized to fit your weanling’s needs.

After the balanced forage base of the diet is in place, it’s relatively simple to supplement the diet as needed based on your youngster’s growth and weight. Both rapidly growing babies and lactating mares usually do need a more concentrated source of calories than forage can provide to hold a good body condition. However, letting your weanling get too fat is a big mistake.

Research clearly shows that overweight young horses are at higher risk for developmental bone and joint disease. Here’s a good guideline: It should be easy to feel your weanling’s ribs at all times. Think lanky teenager! Bellies should be nicely tucked and streamlined. You want good muscular development, not a thick layer of fat masquerading for muscle.

Analyze the forage portion of your youngster’s diet, whether made up of hay or pasture, as the first step to building a nutrition program.

You can also feed—as needed—commercial concentrate mixes that are mineral supplemented and balanced to boost the calories coming from hay. Lower starch options are now available and rely more on easily fermented fiber sources such as beet pulp and soy hulls, which can provide calories equivalent to an equal amount of oats.

Avoid high fat. Look for feeds that have preferably no more than 6% to 8% fat in the analysis. Your veterinary nutrition professional also can help you find recipes for homemade alternatives to commercial grain mixes that are balanced in the major minerals calcium and phosphorus and won’t upset your balanced forage base. An example of this is a 50:50 blend of grade 1 whole oats and beet pulp. Other combinations of alfalfa or beet pulp with oats or brans are also possible.

There are also a few important "extras" to include in your youngster’s diet:

• Saccharomyces cerevisiae yeast or a probiotic containing the strain Propionibacterium will help protect the large bowel from acidity if there is any spillover of undigested grain.

• Vitamin E, 2 IU (international units) per pound, is advisable for animals not on fresh, green pasture.

• Stabilized ground flax seed or freshly ground flax, ½ ounce per 100 pounds of bodyweight, will replace the omega-3 fatty acids missing from diets not based on

pasture. Do not use linseed meal (this has the fat removed) or ground flax that has not been stabilized.

• Plain salt should be available at all times. Coarsely ground livestock salt, available from farm stores and livestock supplies, is often consumed more readily than salt from blocks.

It takes a little bit of work to get an appropriate, balanced nutrition program set up for your weanlings, but the benefits are tremendous. You’ll see gleaming coats, good muscle development, a strong skeleton, and strong immune system all emerging. The feeding plan developed for weanlings is also appropriate for pregnant and lactating mares so you can rest assured you are meeting their high needs, as well.