Traditionally, it is common to give all horses concentrate feed (pellets). However, in recent years, you can see that the science is shifting. If your horse is not in a pasture 24 hours a day, then good hay (unpacked), that is not dusty or moldy, is the basis of the diet in combination with a concentrated mineral pellet. All horses need roughage, in ample quantities, spread throughout the day. Your horse's digestive system cannot function without it.

Hay lacks sufficient minerals

Minerals are essential for your horse. They, for example, ensure healthy bones, hooves, coat, and almost all bodily processes. They are also building materials for pregnant mares. Minerals need to be easily absorbable and present in the correct proportions in the feed because they also influence each other. Dutch hay almost never contains all the minerals that your horse needs. This is partly due to the type of soil on which the grass grows and partly due to the fertilization strategy. To ensure that your horse receives enough, easily absorbable, minerals and trace elements, a supplement is necessary. For most horses that do not engage in top sports, it is better to use a balancer for this. A balancer is a special pellet or cookie that contains all the daily required vitamins, minerals, and trace elements. There are many different brands available, such as Metazoa, Vitalbix, Pavo Vital, or Equilin.

Provide variety in roughage

In the wild, horses eat many different plants and herbs. They need that as well. Therefore, introduce variety into the ration. For example, you can let your horse graze in verges, offer willow branches in the paddock, or pick and offer nettles occasionally (after a few hours of drying). A herbal-rich pasture is, of course, fantastic. If your horse receives little herbs, a supplement with liquid or dried herbs can be ideal. Think, for example, of offering liquid nettle in a water trough!

Watch out for grains in concentrate feed

Although concentrate feed is easy to feed and many people are accustomed to it, it is not always the best solution for a horse. Concentrate feed often contains many grains, such as wheat, corn, rye, and barley. These grains are full of carbohydrates and starch, which are converted into glucose in the horse's body. Unfortunately, you do not see this on the front of the feed bag, but you have to carefully read the ingredients list. There are many different names, such as: corn, wheat products (grits and whole), barley, oat hulls, molasses, corn meal, oat products (hulls and whole), spelt, popped corn, oats, wheat bran, sugar cane molasses, etc.

Not all horses do well on grains. Especially horses with summer eczema, insulin resistance, sensitivity to laminitis, PSSM1, Cushing's, or EMS (equine metabolic syndrome) do better with as few carbohydrates and starch as possible. Moreover, several studies have shown that certain substances in grains hinder the absorption of minerals.

Grains have a negative effect on the absorption of minerals

Grains contain the substance phytate or phytic acid. It has been shown to inhibit the absorption of magnesium. In human studies, it also reduced the absorption of calcium by as much as 52%. Other minerals are also less well absorbed when the feed has a high phytate content. Grains also contain gluten. Gluten contains gliadin, which can make the lining of the small intestine more permeable to macromolecules. With a fancy term, you call it a hyperpermeable intestine. It means greater permeability, allowing substances to pass through the intestinal wall that you would rather not have. It can lead to a higher burden of waste substances in your horse. A weakened intestinal barrier can also cause damage because medications such as painkillers affect the intestinal mucosa. Also, mycotoxins, waste substances from molds, cause many problems in horses, such as liver problems. The molds that produce mycotoxins grow well when a horse is fed a lot of grains.

Therefore, it is advisable to feed all horses grain-free. Not only horses with a condition, but all horses. Grains limit the absorption of minerals, leading to an increased mineral requirement and an imbalance in mineral needs.

What about energy then?

We are often asked if horses will become lethargic if they do not receive much or any concentrate feed. This is not the case, but horses do need some time to adjust, and that takes a while. The "energy substance" in roughage is cellulose, while in concentrate feed, the main energy source consists of starch. Starch is converted into glucose and is absorbed only by the blood. Cellulose is converted into volatile fatty acids that are absorbed by the body to create energy. In nature, cellulose is the largest energy source for horses' bodies. Thanks to their smart partnership with gut bacteria, horses get energy from plant material such as grass and hay. Digestion releases fatty acids that provide energy. Especially when horses have sufficient daily exercise, you will see that they have more than enough energy, specifically without the sugars and starch from concentrate feed. And of course, the horse will experience a temporary dip in energy when switching, but see that as detoxing from a sugar addiction. The gut flora needs to recover, and that will take some time. After this period, you will notice that the horse has more than enough energy to do its work. If you are looking for an extra energy source, choose an oil where omega 3 (EPA and DHA) is readily available such as in salmon oil.

Conclusion: Should I supplement with minerals?

A mineral supplement can be a good idea. However, the minerals in the supplement should be easily absorbable and in the correct proportions, preferably liquid such as concentrated Bering Sea water. In seawater, you can find all available minerals on Earth. If you give concentrate feed, a supplement is necessary to compensate for the reduced mineral absorption caused by the grains in the pellets. Even better is to replace the concentrate feed with a balancer pellet such as Metazoa, Vitalbix, Pavo Vital, or Equilin. If you only provide hay and a balancer, it may be helpful to give minerals from the sea at certain times. For example, during a dip in the immune system, during shedding, when changing pasture, or in the days before and after heavy exercise. A mineral supplement is not a replacement for a complete diet, but an addition for horses that need something extra. If you have a liquid mineral supplement, give your horse the choice and add the minerals to a separate water trough.

Sources:

Al Hasan, S.M., Hassan, M., Saha, S. et al. Dietary phytate intake inhibits the bioavailability of iron and calcium in the diets of pregnant women in rural Bangladesh: a cross-sectional study. BMC Nutr 2, 24 (2016). https://doi.org/10.1186/s40795-016-0064-8.

https://bmcnutr.biomedcentral.com/articles/10.1186/s40795-016-0064-8

Josef Pallauf, Manfred Pietsch, Gerald Rimbach. Dietary phytate reduces magnesium bioavailability in growing rats. Nutrition Research, Volume 18, Issue 6, 1998.

https://www.sciencedirect.com/science/article/abs/pii/S0271531798000852

Shimada S, Tanigawa T, Watanabe T, Nakata A, Sugimura N, Itani S, et al. (2019) Involvement of gliadin, a component of wheat gluten, in increased intestinal permeability leading to non-steroidal anti-inflammatory drug-induced small-intestinal damage. PLoS ONE 14(2): e0211436. https://doi.org/10.1371/journal.pone.0211436

Van Doorn DA, Everts H, Wouterse H, Beynen AC. The apparent digestibility of phytate phosphorus and the influence of supplemental phytase in horses. J Anim Sci. 2004 Jun;82(6):1756-63. doi: 10.2527/2004.8261756x. PMID: 15217003.

https://pubmed.ncbi.nlm.nih.gov/15217003/