Jyme L. Nichols, Director of Nutrition, Bluebonnet Feeds & Stride Animal Health
The human digestive tract and equine digestive tract have surprising similarities. The burden of human digestive diseases remains staggering in the United States, according to a recent study sponsored by the National Institute of Health. Many diseases of the human digestive tract are a result of not fully digesting our foods which can result in irritating symptoms such as intestinal gas, bloating, cramping, heartburn, and diarrhea. Interestingly enough, horses may suffer many of the same digestive discomforts from poorly digested foods. A new shift in nutritional health is emerging as the use of enzymes in the daily diet is becoming more common in both humans and horses.
Enzymes are responsible for thousands of metabolic processes that sustain life. When horses eat food, they don’t absorb food, they instead absorb nutrients. Food that a horse eats must first be converted to absorbable nutrients such as amino acids (from protein), fatty acids (from fat), and simple sugars (from carbohydrates). Enzymes act as a catalyst for this metabolic conversion from food to nutrients. In simple terms, enzymes are required to break down food in the digestive tract so that a horse can utilize the nutrients the food provides.
Enzymes are very specific to the substrate in which they interact with, meaning enzymes are not one-size-fits-all. To put this in perspective, consider how a padlock requires a specific key in order to be unlocked. Enzymes are a lot like a key, and food is a lot like a padlock. Food travels through the horse’s digestive tract waiting to meet up with the exact enzyme needed to “unlock the bond” so that smaller, more easily absorbed nutrients can be released. These nutrients are then absorbed and utilized by the horse.
As you look at feed labels and are determining which enzymes might be beneficial to a horse it is important to know which enzymes are appropriate for the major nutrients that a horse requires on a daily basis. For example, protein in the diet is broken down to amino acids by proteolytic enzymes, or proteases. Cellulose in forage requires the enzyme cellulase, and the enzyme required for digestion of fat is lipase. Amylaseis the enzyme that helps in the digestion of starch.
It is very important that starch be broken down and digested in the small intestine. If a horse is fed excessive volumes of starch (i.e. oats or sweet feed) it is possible for the small intestine to become overloaded which forces starch into the hind gut. When excess starch reaches the hind gut there is a high risk for the development of hind gut ulceration, acidosis, colic, and founder. By adding additional amounts of the enzyme amylase to the diet, a horse may break down and absorb more starch in the small intestine therefore reducing the chance of excess starch spilling over to the hind gut.
A research trial by Salem and colleagues published in the September 2015 issue of Journal of Equine Veterinary Scienceshowed that after only 15 days of adding enzymes to the diet, horses consumed more feed and digestibility was improved. An increase in digestibility and nutrient utilization leads to an improvement in feed efficiency. By improving feed efficiency other benefits are likely to follow such as better body condition and hair coat, increased weight gain, fewer instances of mild colic, reduction of diarrhea and loose stool, better attitude, and overall improvements in performance.
Horses do produce their own enzymes naturally, but there are certain situations that could disrupt this normal process. Some of these scenarios may include disease, low grade inflammation of the digestive tract, aging, pH imbalances, and chronic stress from training and hauling. We ask a lot of our horses every day. We have molded their feeding times to best fit our own schedules and they are constantly being exposed to new high-anxiety situations – all of which can negatively impact the digestive environment. Choosing a feed or providing a supplement that contains added enzymes is a small but effective way to help your horse survive the daily battles of his life that we often times overlook.