We’ve already seen how extruded feeds can promote digestibility, support overall gut health and increase the bioavailability of essential nutrients.

So, what about starch and sugar? Abundant in most concentrated feeds, these carbohydrates can cause problems for some horses, including digestive ills that might lead to colic or laminitis (founder). This is because the horse’s digestive system is geared more toward processing the fiber in grass or hay than the added starch and sugar in grain and pellets.

To better understand this, let’s take another peek at the equine gastrointestinal tract, which consists of the foregut and the hindgut. The foregut (the stomach and small intestines) is where proteins, carbohydrates (starch and sugar), fats, vitamins and minerals are absorbed. The hindgut (the cecum and large intestine) is where forage and other fibers are broken down, fermented and converted into usable energy, protein and other nutrients.

While most horses need a certain amount of dietary starch and sugar, too much can be unhealthy.  It is important to consider all sources of starch and sugar, both hay and grain.  When additional starch and sugar is introduced to a horse, such as in a concentrated feed, it can be more than a horse’s system can handle. If there is too much for the foregut to process and absorb efficiently, undigested starch and/or sugar ends up in the hindgut, which is not designed to process either. The resulting alteration in the hindgut’s normal microbial and enzyme balances, can lead to potentially serious problems. Fermentation of excess starch, for example, can produce gas that can leads to colic and laminitis.

Can extruded feed help? Yes! During the pressure-cooking stage of extrusion, the starch and protein bonds in the feed are broken, increasing their digestibility and availability. Because extruded feed promotes increased starch digestion in the foregut, it reduces the risk of undigested starches passing to the hindgut and causing problems.

If your horse is particularly sensitive to starch and/or sugar, you might consider switching him to a diet that is lower in both. Horses that can benefit from such a diet include those with ulcers or Equine Gastric Ulcer Syndrome (EGUS); a history of laminitis, digestive disease or colic; insulin resistance (IR); Equine Metabolic Syndrome (EMS); Cushing’s Disease (PPID); Leaky Gut Syndrome; Polysaccharide Storage Myopathy (PSSM) or Equine Polysaccharide Storage Myopathy (EPSM).

Young, growing horses, as well as senior horses with metabolic concerns and those in certain management situations, can also benefit from lower levels of starch and/or sugar. When in doubt, consult your veterinarian.