Most everyone has a basic understanding of intestinal tract bacteria and that there are good and bad bacteria that can play important roles in health or disease. Many of us are also familiar with the term probiotic, but what is a prebiotic and how can both of these support health and wellness. In recent years there has been a great deal of interest and research toward understanding the microorganisms that live in gastrointestinal system and how probiotics and prebiotics could provide an exciting world of possible health benefits.  

 

Collectively all these living microorganisms are known as “gastrointestinal (GI) microflora” and they live through out the entire gastrointestinal system from the mouth to the rectum.  While the GI Microflora primarily consists of bacteria, protozoa and yeasts are also part of this interesting ecology of living organisms. To put in perspective how important the GI Microflora is, all one has to do is consider the sheer size of this microbial population. It has been estimated that the number of GI Microflora cells are 10 times more than all the mammalian cells in the body. In our horses, within one gram of digestive fluid there can be 5-10 billion bacteria consisting of 50 or more species. The GI Microflora is so large and important that it could be considered another of the body’s organs. Thus because of its sheer size any minor changes in the GI Microflora will have significant influence on the rest of the body.

 

The classical role attributed the GI Microflora is digestion.  Mammalian cells lack the enzymes systems to digest structural plant fibers. For example, plant cellulose is a type of sugar whose carbon bonds can not be broken down or digested by mammalian cells. The GI Microflora can break these bonds and through fermentation provide volatile fatty acids (VFA) that can be absorb by the intestinal cells. In our horses, VFA production through microbial sugar fermentation is the primary source of calories.   The intestinal microbes are also thought to be involved in protein digestion, amino acid synthesis and even lipid digestion and storage.  So, when you offer your horse a flake of hay, you are really feeding the intestinal microbes that must first digest the hay.   The health and well being of these microbes will directly affect the health and well being of the horse. Thus the microbes have a mutual symbiosis with the horse and through diet and supplements we may be able to optimize this symbiosis.

 

The populations of GI Microflora are a direct result of the diet consumed. These microbes will adjust to dietary changes if given enough time and support. Colic is still the number one cause of death in horses and we know that any recent change in the grain or forage can increase the risked of colic. Current thinking is the trigger for colic probably begins with changes in the microflora. As the microbes become stressed, die or change in numbers or species, they will profoundly influence GI physiology. The end result of microbial stress is seen by you as a horse with colic, diarrhea, weight loss or even poor behavior.   Could we lessen the risk of colic and other gastrointestinal challenges through support of the GI Microbes?

 

What about stress with our horses and how this may influence the intestinal microbes? We have taken animal that was designed to be free roaming and consume forage and domesticated him to a box stall and feed him a grain concentrates that his system was not engineered for.  On top of this we often then travel and compete with our horses and this adds additional stress through changing water, routine and environment. All of these stressors will affect microbial balance and the end results can manifest in a myriad of challenges in our horses. If we could help support the microbes to mitigate this constant stress would it be of benefit to the general health of our horses?

 

The root terms for the word probiotic literally mean “for life”. Probiotics are defined as living microorganisms that provide health benefits. Traditionally probiotics consist of bacteria but live yeast cells can also be considered to have probiotic functions. Many of us are aware of the digestive benefits of yogurt and the live bacteria or probiotics in these fermented dairy products provide some of these benefits.  For probiotics to be effected they must be alive and consumed frequently in adequate numbers.  Research is now focused on which strains of microbes are most efficacious as well as microbial viability, shelf life and the numbers of organism needed to convey health benefits.

 

How do probiotics provide support to the GI Microflora and health benefits? Competitive inhibition of detrimental microbes is one way probiotics may provide digestive health support. The daily seeding of good microbes simply compete with bad microbes for substrates to digest and thrive. It is also thought that metabolic byproducts that are released from the probiotic microbes can encourage and enhance the health and numbers of resident GI Microbes. For example, some probiotics can improve the pH of the intestinal tract which enhances the beneficial microbes but discourages the proliferation of detrimental microbes. Probiotics can also directly improve the digestion of food substrates which translates into improved absorption of nutrients and overall improve digestive health. Lastly, it also thought that probiotics can directly influence the health and development of the billions enterocytes or intestinal lining cells. When these cells flourish there can be profound health advantages.  

 

An area of intriguing research is how probiotics can influence the systemic immune system. A majority of the body’s circulating white blood cells are located near the intestinal enterocytes to constantly guard against pathogenic microbes and unwanted molecules or debris from entering into systemic circulation. There is evidence that the GI Microflora will influence the intestinal white blood cells which can have systemic effects on allergies and immune challenges. It is also thought that probiotics can help decrease gastrointestinal inflammation which will help modulate the systemic immune system. In simple terms, probiotics help reduce the stress and demands of local intestinal immune cells which can have systemic benefits.  This may explain why probiotics have been shown to be of benefits with some allergies and systemic immune system challenges.

 

What is a prebiotic and how can these influence digestive health? A prebiotic is a non-nutritional compound that will enhance the composition or activity of the gastrointestinal microflora. In other words, a prebiotic will help good microbes to increase their benefits on digestive health. Many prebiotics are fermentation byproducts such as mannan oligosaccharides that are derived from the cell walls of the yeast Saccharomyces. Oligosaccharides are sugars that will prevent pathogenic bacteria like Salmonella from attaching to the enterocytes. If bad bacteria are prevented from attaching to the intestinal cells they will pass on with out causing problems. Another example of a prebiotic is psyllium which will selectively help the good microbes to flourish and also provide direct health benefits to enterocyte health.

 

The best of both worlds is to combine probiotics with prebiotics.   The daily feeding of large numbers of live beneficial microbes along with prebiotics to help the good microbes flourish has great potential to optimize digestive health.  

 

The research world is full of promising studies that demonstrate great hope for probiotics and prebiotics improving health.  It is exciting to learn about all the preliminary positive effects these products may have. The following is a list of some of the current research in various species. All of these demonstrate the great potential with probiotics and prebiotics.

 

We have a great deal to learn about probiotics and prebiotics and this research is just beginning. A common thread through all of this research is that many health challenges begin in the gastrointestinal system and specifically with the GI Microflora. If we can learn of ways to support the microflora through effective probiotics and prebiotics it is apparent we could impact a wide variety of health challenges.  

 

With specific reference to equine health the potential benefits could be great. We all would like to find ways to reduce the risk of colic and it is thought that the equine microflora is involved. Could a horse with poor hair coat, poor performance, behavior challenges, allergies or even poor hoof health all have a common link to the GI Microflora?

 

 At Arenus one of our primary areas of research focus has been in support of equine digestive health. Our Assure line of products provides digestive health support for a wide variety of GI challenges. Probiotics and prebiotics are some of the ingredients that can be found in the Assure products. Assure and Assure Plus are the only digestive health supplements with validated university research demonstrating significant sand clearance. This research was presented at the 2007 American Equine Practitioners’ Symposium.

 

While not all horses suffer from sand accumulation, this research demonstrates how these products can modulate intestinal motility and inflammation.   The guaranteed concentrations of probiotics in the Assure products are much higher than traditional products. Many products only provide 1-2 billion microbes, while The Assure System (Assure and Assure Plus) will provide your horse upwards of 40 billion microbes per day.   Not all probiotic products are the same, but the Assure line is focused on quality and research. At Arenus we are currently investing in additional research to validate the benefits of the Assure products is a wide range of health challenges. Stay tune as we hope to bring you evidence of the exciting world of possible health benefits that the Assure family of products can offer.

Kenneth J. Kopp DVM

Arenus Technical Service Veterinarian