Gastric and Intestinal Health Overview

The gastrointestinal (GI) system plays important roles in your horse including:
• Defence against ingested pathogens
• Breakdown of feedstuffs
• Absorption of nutrients
• Providing a barrier between GI contents (which are ‘external’ to the horse) and the interior
• Housing commensal or beneficial microbiome
• Direct communication and interactions with the innate immune system
• Communications to and from the brain, and other parts of the body

As you can see, the GI system is very important to the horse’s wellbeing, as well as to health and performance. Good nutrition is key to achieving and maintaining a healthy GI system. Effective stress management is also very important. Here, we will focus on nutrition.

In addition to nutrient absorption, the gastrointestinal tract also interacts with the immune system and serves as a barrier to keep pathogens from passing to the internal body fluids and tissues.

By nutrition we do not just mean the macronutrients (carbohydrate, protein, fat), vitamins, minerals and water that are also essential for health. We also mean the numerous molecules in many food materials that exert effects on often multiple body systems to help make a healthy horse even healthier. We refer to these molecules, or the products from which they come, as nutraceuticals – nutrients that exert health benefits. Some of the health benefits are general, and some are specific to certain systems.

What is the case for maintaining GI health? Current estimates place more than 90% of performance horses with gastric ulcers and a similar number having some form of hindgut inflammation or ulcers such as colitis. Collectively, these unhealthy GI conditions result in a range of signs that, when collectively taken together, are now know as equine leaky gut syndrome (LGS). Equine LGS bears many similarities to irritable bowel syndrome, Crohn’s disease, etc. in people. The mechanisms underlying leaky gut in mammals bears similarities across species, and effective treatments are also similar across species.

There is bi-directional flow of signals between gut and brain and immune system. GI health affects the health of all major organ systems. Optimal GI health is required for optimal performance.

Can good nutrition prevent LGS from occurring? The short answer is yes, and maybe. The maybe is because stressors and ingested substances that detrimental to GI health may occur in the presence of great nutrition, such that LGS occurs. These two elements, ingested substances and stressors, also come down to good equine management practices.
Ingestion of pathogenic organisms on the ground, on foliage or foliage itself, fence posts and other items can disrupt GI health. The acid environment of the stomach provides some defense against pathogens but many, including harmful bacteria, fungi, plant matter pass through the stomach to make their way down the intestinal tract. Some act as poisons directly on the intestinal epithelial cells (IECs), causing the intestinal barrier to fail in places, causing leakiness. Some act as poisons against beneficial bacteria and fungi in the GI system, resulting in proliferation of harmful bacteria / fungi that produce and secrete poisons. The innate immune system can deal with small numbers of these harmful organisms and compounds, but are overwhelmed when stressors are excessive.

The leaky gut allows pathogens to cross the intestinal barrier and infect the intestinal wall, as well as other tissues by transport within the blood. Tight junctions between intestinal epithelial cells help maintain healthy gut barrier function, but are damaged by many pathogens.

Stressors include ingestion of pathogenic substances, unaccustomed exercise and activities, high ambient heat and humidity, rough or poor handling, inadequate turn out durations, interactions with other horses or people, transport, noise, vermin, other health ailments (i.e. lameness), as well as medications that are used to treat other health concerns. Bute, for example, is destructive to the GI system and should only be used by veterinary prescription for as short a time as possible.

The keys to a healthy GI system. Good nutrition management and good stress management. Let us first deal with stress management.
By stress management we do not mean to minimise or reduce stresses. Indeed, stress is necessary while excessive stress is detrimental. Environmental stresses and handling stresses should be well managed to try to keep the horse calm and free from anxiety. Rough or unkind handling by any person or any horse is a major stressor. Great care should be taken when choosing which people and which horses your horse should be around. Horses evolved in great, open spaces and generally do not do well when confined to a stall. If a stall is used for housing, turnout time needs to be daily and for as generous a time as is possible. Stall areas must always be well ventilated to prevent buildup of noxious dust and gases that find their way into the respiratory system. Cold is better than heat – horses have a lot of muscle with which to generate heat, but a relatively small skin surface area to get rid of excess heat. Heat stress can be managed by avoiding use of blankets when the horse is warm, and by keeping the horse in shaded and breezy locations whenever possible. Keeping the horse well hydrated is very important to prevent excessive heat stress and heat injury.
Nutrition management begins with high quality forage, whether it be pasture, hay or hay cubes. High quality forage means that is free of pathogens such as molds (releasing mycotoxins), poisonous bacteria from the ground or other surfaces, poisonous plants, or toxins that enter as part of processing and handling. If you buy hay and notice that it is dusty, and hope that steaming or wetting the hay may be an improvement you may be making a big mistake. The most common type of dust in hay is from mold, and the mycotoxins from molds are very detrimental to the GI and immune systems. If you are uncertainly about the quality of the forage, then have it tested for nutrients AND for pathogens. This is far cheaper than the health care costs of being negligent about forage quality. Ideally, horses should have access to forage and water 24 / 7. This is very beneficial for an even plane of GI health, immune health, mental health and whole body energy balance.

The next item for nutrition management is taking of energy, as well as providing the right balance of minerals (and electrolytes) and vitamins. This can be achieved by using high quality complete feeds. A tendency these days is to over-provide complete feeds, resulting in a horse with too much condition (7 or greater using Henneke’s 9-point scale can be considered unhealthy). Complete feeds serve two main purposes: provide the right balance of energy sources to meet the horse’s activity demands, and to provide adequate vitamins and minerals. Sometimes feed should not be provided, but this then requires that appropriate amounts of vitamins and minerals are provided, at least once daily, with something that the horse can ingest – for example a proper amount of a vitamin-mineral mix can be added to wetted feed in a way that allows the horse to consume what is needed by eating and drinking.
At this point, if your horse is a healthy pasture pony and not engaged in performance activities, nothing else need to be considered. But if your horse is a performance horse, regularly engaged in training, competition and transport, then you need to think about optimising health because the stressors can be massive.

Nutraceuticals specific to GI health. There are hundreds of molecules that are beneficial to GI health. Many times we still do not which molecules are important when we supply our horse a beneficial nutraceutical product. We know it works, the scientific studies show that certain ingredients are beneficial, but we still do not have a good idea of which molecules or combination of molecules present in the product are responsible for the benefits. Therefore we tend to feed products, as opposed to molecules (which may then be a drug). We also know that there are some molecules, and also some products that specifically work very well for maintaining or achieving a healthy GI system.
OVVET, using evidence-based research followed by owner and veterinary observation of horses over a period of weeks to years, has developed two effective GI health products. There are OVVET Gastric Care and OVVET Gastric Control Gold.

The ingredients
The ingredients common to both gastric products are milled Golden Flaxseed, Levucell®, Reishi mushroom powder, and powdered omega fatty acids.
Additional ingredients within Gastric Care are Alkosel®, Laltide®, oat flour, sodium bicarbonate and trehalose.
The additional ingredient within the Gastric Control Gold is Fermaid Ease 187.

Golden Flaxseed
Golden flaxseed is a rich, natural source of beneficial unsaturated and polyunsaturated fatty acids (PUFAs). Alpha-linolenic acid (ALA) is an omega-3 fatty acid and present in milled flaxseed at 22%, and the omega-6 fatty acid linoleic acid is at 7%. ALA is easily converted by the body to the other beneficial PUFAs EPA (eicosapentanoic acid) and DHA (docosahexanoic acid).
• Supports maintenance of healthy, robust cells
• Supports cell and tissue anti-inflammatory activity
• Support immune health
• Supports generation of PUFAs from ALA

Powdered Omega Fatty Acids from Fish Oil
This natural and green-harvested fish oil is a rich source of DHA (docosahexanoic acid) and EPA (eicosapentanoic acid) and has a total fatty acid content of 72% by weight.

Evidence-based research shows that these fatty acids exert anti-inflammatory and anti-oxidant effects on cells and tissues in living mammals, as well has having beneficial effects on cardiovascular health, immune health and brain function.
• Supports maintenance of healthy, robust cells
• Supports cell and tissue anti-inflammatory activity
• Support immune health

Levucell ®
The probiotic Levucell® is Lallemand’s proprietary strain of live Saccharomyces cerevisiae boulardii (CNCM I-1079) and is termed a digestibility enhancer for monogastric animals. It is especially associated with oxygen scavenging in the gut, promoting the proliferation of beneficial or commensal bacterial populations. The products produced by these beneficial gut bacteria promote gut health in many ways including maintaining barrier function, communication with other but microbiota, and with cells of the intestinal epithelium and the innate immune system.
• Supports healthy gut microbiota
• Supports healthy gut structure and function
• Supports gut barrier functions
• Supports immune health

Reishi mushroom powder
Reishi mushroom (also known as Ganoderma lucidum) has been used in traditional oriental medicines for thousands of years. Evidence-based research shows specific effects including anti-inflammatory, anti-allergic, anti-diabetic, anti-cancer and promotes cardiovascular health, healing of gastro-intestinal ulcers, immune health, and liver health. Some, but not all of these beneficial effects are associated with the beta-glucans.
• Contains beta-glucan prebiotics to support beneficial gut microbiome
• Supports maintenance of healthy tissues
• Supports immune health

Alkosel® is Lallemand’s proprietary inactivated, whole cell, selenium-enriched yeast (S. cerevisiae), providing a natural source of highly bioavailable L(+) selenomethionine. Selenium directly interacts with vitamin E (alpha-tocopherol) in the body, and has powerful anti-inflammatory and anti-oxidant activities that support tissue and wound healing, and help maintain healthy tissues.
• Supports tissue anti-oxidative and anti-inflammatory activities
• Supports tissue and wound healing

Laltide® is Lallemand’s proprietary yeast (S. cerevisiae) product that provides natural sources of nucleosides and nucleotides, free amino acids & peptides, glutamic acid and other important nutrients. Many of these are directly beneficial for gut health including barrier function (glutamine, threonine, arginine) and immune health, and all are used in the body to maintain healthy cells and tissues.
• Supports tissue protein synthesis
• Support cell and tissue repair

Fermaid® Ease 187
Fermaid® Ease 187 is Lallemand’s proprietary product of the fermentation of micronized soy meal. Fermentation of soy meal with Lactobacillus delbrueckii lactis Rosell-187 results in the generation of numerous molecules beneficial to gut and immune system health, specifically exerting anti-inflammatory and wound healing effects on damaged tissues. Evidence-based research shows accelerated rate of healing of gastric ulcers in horses when using products containing Fermaid® Ease 187 (Link to Lallemand article
• Maintains the integrity of the digestive tract and supports cell regeneration
• Contributes to the well-being of your horse – associated with reduction of clinical signs associated with stress
• Supports and maintains the health of your horse even during period of intense training and performance

Gluten Free Oat Flour
Whole, ground oat flour is a rich source of beta-glucans that are present within the hulls. Beta-glucans are associated with numerous health benefits including anti-inflammation, immune-stimulating, and gut microbiota-modulating activities, ability to beneficially modify short-chain fatty acids (SCFAs) production, protective effects against an intestinal parasite, protection against bacterial infection, and a synergistic effect in antibody-dependent cellular cytotoxicity. Beta-glucans are a non-starch polysaccharide and contribute to the class of carbohydrate nutrients termed dietary fiber. Beta-glucans present in oat bran and oat flour are not degraded in the stomach and the small intestine, and are therefore delivered to the large intestine where they provide a source of non-starch polysaccharides to microbiota of the large intestine.
• Contains beta-glucan prebiotics to support beneficial gut microbiome
• Supports gut health
• Support immune health

Sodium bicarbonate
Sodium bicarbonate (baking soda) is used as a gentle way to elevate gut pH due to its antacid activity. Slightly raising gut pH is also associated with maintenance of a beneficial gut microbiome.
• Supports gastric and intestinal health
• Supports beneficial gut microbiome

Trehalose is a double-glucose disaccharide that, in addition to being a safe, natural sweetener is important in the regular of tissue repair through a process termed autophagy.
• Support gut health

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