Prebiotics and Probiotics in horses

Prebiotics and Probiotics in horses

The hindgut (cecum and colon) of the horse has a microbial population (microbes: bacteria, yeast, fungi) that ferment and breakdown fibre. Without these microbes in the hindgut, horses would not be able to digest and utilize plant material such as hay and pasture. The microbes in the hindgut break down and ferment fibre producing volatile fatty acids that serve as a significant energy source and synthesize B vitamins and other nutrients essential to the health and wellbeing of the horse. In order to efficiently digest fiber, the microbial population of the hindgut must be healthy and their numbers maintained at appropriate levels. There are additives such as probiotics and prebiotics that can be added to the feed or used as supplements that may assist in keeping the microbes in the hindgut healthy and primed for proper digestion.



Prebiotics are non-digestible food ingredients that stimulate the growth or activity of bacteria in the digestive system. Most (but not all) prebiotics are carbohydrates in form of long chains of sugar molecules bound together. MOS is a non-digestible sugar that has the same binding site on its surface as the small intestine. Many pathogens bind to the wall (surface carbohydrates) of the intestine and gain access to start their damage and the disease process. Please see picture 1. When you feed your horse prebiotics such as MOS the bad bacteria adhere to these sugars. Since these sugars (prebiotics) are non-digestible, the harmful pathogens are carried on through the digestive tract rather than causing disease. Please see picture 2.


Pro and Prebiotics - 1
Picture 1
Pro and Prebiotics - 2
Picture 2

We at Hygain utilize MOS as it is particularly effective at binding pathogens. MOS is derived from the cell wall of a specific yeast culture named Saccharomyces cerevisiae 1026 and provides an original natural solution to intestinal issues. Prebiotics promote good bacteria and builds natural defenses thereby maximizing performance. Further research has shown that MOS can boost immunoglobulins in colostrum by supplementing the dam with MOS prior to foaling.



The term probiotic derived from the Greek words “for” and “life” and is a life microbe thought to be beneficial to the host organism. Another common term used for probiotics is direct fed microbials (DFM) as they can be supplemented to the horse’s diet with the purpose of keeping the hindgut microbial population stabilized. The horses hindgut can be easily disrupted by an abrupt change in feed, any kind of low or high level stress or strenuous performance can damage or destroy microbes in the hindgut. Also, a high-grain, high-concentrate, low-fiber diet may cause a disruption in the gut. Therefore, it is beneficial to have a small amount of these important probiotics added to the diet on a daily basis. At HYGAIN® we utilize a live yeast culture based on Saccharomyces cerevisiae strain 1026. Research on this specific probiotic in horses has shown increased fiber and phosphorous digestion, which led to further studies showing increased whither heights in foals from dams supplemented with this probiotic throughout gestation. The life cycle of some of these microbes within the gut is only around 15 minutes. Since microbes are living organisms, people often ask about shelf life and whether the microbes actually make it to the hindgut when fed or if they can withstand the temperatures involved in feed processing. HYGAIN® has carefully selected specific probiotics , because of its microencapsulated technology, which enables it to travel unharmed to the hindgut where it is most effective and its ability to withstand feed processing temperatures.


Use of Probiotics and Prebiotics

Hygain TrucareHygain Trubreed

Both prebiotics and probiotics are commonly used in high performance horse diets as it can help make a difference in keeping the horse functioning at its best. Young and aged horses also benefit from probiotic and prebiotic use as their intestinal tracts usually are not functioning at peak efficiency. Foals for instance lack a fully balanced level of bacteria in their systems and thus cannot completely and effectively digest food. Aged horses on the other hand often have intestinal scarring or other conditions that make it difficult for them to digest and absorb their food. Hygain has recognized these weaknesses and included live yeast and MOS in HYGAIN® EQUINE SENIOR® and HYGAIN TRU CARE® for the older horse and HYGAIN TRU BREED®, HYGAIN® GROTORQUE® and HYGAIN® STUDTORQUE® for the broodmare and young horse. Other scenarios where the use of these products may be important is in re-establishing proper gut function after the horse has been ill, off their feed or treated with oral antibiotics that kill some of the beneficial microbes in the hindgut. Medications that kill pathogenic bacteria also kill good ones.


The use of probiotics and prebiotics in horse feed is a valid, research based approach to keeping horses healthy. This is yet another way HYGAIN® utilizes technology to help keep your horse healthy from the inside out.

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