Equine Gut Health: Does Your Horse Really Need a Digestive Supplement?
Gut Health Isn’t Just One Thing
Probiotics, prebiotics, live yeast, postbiotics, herbs… with so many equine digestive supplements available, how do you know what your horse actually needs?
Walk into any feed room and you will find no shortage of products promising to support digestive or gut health. Some focus on probiotics, others contain prebiotics, live yeast, herbs, fibre, pectin or combinations of several different ingredients, but are these products doing the same job?
Here's the problem: "Gut health" isn't one thing and neither is a digestive supplement.
The horse's digestive system is a remarkable piece of biological engineering, designed to turn a steady supply of forage into energy. But the stomach, small intestine and hindgut each have very different jobs, with different requirements and challenges. They don't work in isolation, they work as one interconnected system, where what happens in one part can have a knock-on effect elsewhere. Putting it simply, when one part of the digestive process is disrupted, it can put additional pressure on another.
So before reaching for the biotics, the longest ingredient list or the latest "gut health" trend, it is worth taking a step back.
What actually happens to a mouthful of grass once your horse eats it?
To understand what your horse may, or may not need from a digestive supplement, we first need to understand how the equine digestive system is designed to work.
The digestive process starts in the mouth.
Think about what happens when you chew a piece of gum. You chew, your mouth produces saliva and your digestive system begins preparing for food. You may even notice your stomach rumbling or that familiar "empty stomach" sensation. For us, this is part of the normal digestive response to eating. Horses are not like us, in fact they are more like rabbits - a horse's digestive system is designed around eating for around 16 hours a day!
Horses are hindgut fermenters and have evolved as trickle feeders, unlike us, their stomach produces acid continuously, whether food is arriving or not. Their digestive system is designed for forage to be consumed little and often throughout the day, rather than for long periods without food followed by large meals, and every mouthful of forage does more than provide nutrients - chewing produces saliva.
Equine saliva contains bicarbonate, which provides an important natural source of buffering as the forage enters the stomach. So, eating, chewing, saliva production and stomach acid are all part of one continuous digestive process.
This is why feeding the horse the right diet isn't simply about providing enough calories. The way a horse is fed matters too, when a horse doesn't have enough forage, has long periods without something to chew, or is fed a diet that doesn't reflect how its digestive system is designed to work, that carefully balanced relationship between forage, saliva and stomach acid can be disrupted.
So there is a simple relationship:
Chewing forage → saliva → bicarbonate → natural buffering
Is acid not produced in the stomach?
Yes, the horse's stomach continues to produce hydrochloric acid, that acid is essential, it isn't the enemy. Stomach acid has several important jobs, it helps begin the digestion of protein, activates digestive enzymes and creates the highly acidic environment needed to start breaking down food and controlling microorganisms entering the digestive tract.
The small intestine has a big responsibility!
The stomach then gradually passes its contents into the small intestine, where much of the digestion and absorption of nutrients takes place.
Carbohydrates, amino acids, fatty acids, vitamins and minerals are processed and absorbed here to varying degrees before the remaining material moves into the hindgut.
Horses are hindgut fermenters – but what does that mean?
Unlike humans, who rely primarily on digestion and absorption in the stomach and small intestine, horses rely heavily on the microbial population in their large intestine to ferment fibre. The horse cannot digest plant fibre on its own, instead, billions of microorganisms living in the hindgut break down components of the forage that the horse's own digestive enzymes cannot digest.
This fermentation produces volatile fatty acids, which provide an important source of energy for the horse.
Other animals that are also hindgut fermenters include, rabbits, guinea pigs, rhinoceroses and elephants, but humans are different. We have a microbial population in our large intestine and it does ferment some undigested carbohydrates and fibre, but we are not specialised hindgut fermenters in the same way as a horse. That is one reason forage is such a fundamental part of equine nutrition.
What happens inside the horse's stomach?
This is where the horse's feeding behaviour becomes particularly important, the equine stomach is relatively small (roughly the size of a rugby ball) and is divided broadly into two different regions.
The squamous region (pronounced squee-mous)
The upper part of the stomach is lined with squamous epithelium, unlike the glandular region below it, this area does not have the same protective mucus and bicarbonate barrier making it more vulnerable to exposure to gastric acid.
The glandular region
The lower part of the stomach, including the glandular mucosa, is adapted to cope with the highly acidic environment. It produces mucus and bicarbonate as part of its natural defence system against acid.
The stomach is not simply one big bag of acid, it contains different regions with different structures and different protective mechanisms and that distinction becomes particularly important when we consider how horses eat and exercise.
The forage "mat" isn't just about filling the stomach
When a horse has forage in its stomach, the fibrous material forms a relatively dense layer within the stomach contents. This can help create a physical barrier between the acidic stomach contents below and the more vulnerable squamous region above. However, this isn't a perfect, fixed layer, it can move. Imagine a horse with a stomach containing plenty of forage, now imagine that horse suddenly starts trotting, cantering or working - the contents of the stomach move too.
This is why the combination of stomach acid + exercise + insufficient forage is an important consideration in equine gastric health.
If there is not enough forage present to provide that buffering effect and physical structure, acidic contents can move or "splash" upwards onto the squamous mucosa, the squamous region wasn't designed to sit in contact with gastric acid and repeated exposure can contribute to damage and lesions. This is often referred to as acid splash.
So what should we be looking for? What are the benefits of using an equine digestive supplement?
In truth, many horses can benefit from nutritional support for the demands of modern management. Horses evolved to graze for much of the day, with access to a wide variety of grasses, plants and hedgerow herbs. Today, restricted grazing, limited forage diversity and more controlled diets can mean that their natural variety of dietary inputs is reduced.
This makes it important to consider how we can support the digestive system as a whole, particularly the diverse population of beneficial bacteria that live in the hindgut and play such an important role in fibre fermentation.
So, when choosing a digestive supplement, what should you actually be looking for?
Ideally, ingredients that help support:
- the normal stomach environment
- healthy stomach and intestinal tissues
- normal digestion and nutrient absorption
- efficient fibre fermentation
- a healthy and diverse intestinal microbial population
- normal digestive motility
- a healthy appetite and normal feed intake
But this raises the next question:
Which ingredients can help support these areas?
Think of your horse’s gut as a busy little ecosystem. It is home to billions of bacteria, and keeping the right environment, food supply and balance is important for normal digestion and fibre fermentation.
Prebiotics – the lunchbox
Prebiotics are the food that beneficial gut bacteria can use. Think of them as a lunchbox for the good bacteria, helping provide the nutrients they need to thrive and supporting a healthy, diverse gut microbiome.
Probiotics – the army of good bacteria
Probiotics are live beneficial microorganisms. Think of them as reinforcements for the gut’s army of good bacteria, helping to support a healthy and balanced microbial population.
Postbiotics and yeast-derived nutrients – the support team
Postbiotics are beneficial compounds produced by microorganisms, while yeast-derived nutrients such as nucleotides can provide useful building blocks for rapidly renewing tissues. Together, these types of ingredients can help support healthy gut tissues and a resilient digestive system.
Maerl (calcareous marine algae)
A natural source of calcium and magnesium. Its mineral content provides buffering support in the stomach, helping to maintain a healthy acid base environment. This can support the normal conditions needed for comfortable digestion as feed moves through the digestive tract, great for those with loose droppings.
Seaweed meal
Provides naturally occurring minerals, bioactive compounds and antioxidants that can help support the normal condition of the stomach and intestinal tissues. These compounds also contribute to normal digestive function as nutrients pass through the digestive tract.
Liquorice root
Naturally contains plant compounds and antioxidants that can help support the normal condition of the stomach lining. This provides targeted nutritional support for the stomach as it carries out its important role in mixing and beginning the digestion of feed.
Fenugreek, Mint and Thyme
Traditional digestive botanicals providing a range of plant compounds and antioxidants. They help support normal digestive processes and healthy digestive tissues, from the stomach through to the intestines, complementing the other ingredients in the formulation.
Marshmallow root
A natural source of mucilage, a gel like substance that absorbs water and provides a calming physical layer. It can help support the normal condition of the stomach and intestinal tissues as feed and digestive contents move through the digestive tract.
Milk thistle
A botanical source of antioxidant compounds that help support the body's natural antioxidant defences. This provides nutritional support for healthy digestive tissues and normal cellular function throughout the digestive tract, including the intestines where nutrients are absorbed.
Omega-3 Fatty Acids
Important fatty acids that contribute to healthy cell membranes and a normal inflammatory response. They provide nutritional support for the cells and tissues of the digestive tract, including the stomach and intestines, helping maintain normal digestive function.
Vitamin B1 & B6
Important nutrients involved in energy metabolism, nervous system function and the utilisation of nutrients from the diet. They support the normal digestive processes that allow the horse to break down, absorb and make use of nutrients from its feed, while contributing to normal appetite and energy metabolism.
So, does your horse really need a digestive supplement?
There is no single digestive supplement for every horse’s needs, and supplements should never replace the foundations of good digestive management: plenty of forage, regular fibre intake, appropriate feeding and a balanced diet.
However, modern management, changes in routine, travel, exercise and competition can place additional demands on the digestive system. A well formulated supplement can provide targeted nutritional support alongside good feeding practices.
The key is to look beyond the latest gut health trend and consider what the ingredients actually do, how they work together and which areas of digestion they support.
Good digestive support starts with good feeding. The right supplement simply builds on that foundation.
Looking for broader digestive support?
Acid Aid has been carefully formulated to support the horse's digestive system from the stomach through to the hindgut, combining ingredients selected to support a healthy stomach environment, digestive tissues, small intestine function and the hindgut microbiome.
If you're looking for everyday nutritional support for your horse's digestive health, find out more about Acid Aid and see whether it could be a useful addition to your horse's feeding routine.
FAQS
What are the benefits of using equine gut balancers for horses?
Equine gut balancers like Acid Aid can provide nutritional support for the different parts of the digestive system, helping maintain a healthy stomach environment, normal digestion and a balanced intestinal microbiome. Depending on the formulation, they may combine ingredients that support stomach pH, healthy digestive tissues, fibre fermentation and the intestinal microbial population. They can be particularly useful when a horse's digestive system is under additional pressure from changes in routine, travel, exercise or competition.
What should I look for in an equine digestive supplement?
Look for a formulation that takes a broad approach to digestive support rather than relying on a single ingredient. Depending on your horse's needs, useful ingredients may include sources of calcium and magnesium to support a healthy stomach pH, plant ingredients to support healthy digestive tissues, and probiotic and prebiotic ingredients to support the intestinal microbiome. It is also important to consider the amount provided at the recommended feeding rate, rather than simply looking at how many ingredients appear on the label.
What ingredients are commonly used in horse digestive supplements?
Equine digestive supplements can contain a variety of ingredients, depending on the area of digestive support they are designed to provide. Common ingredients include buffers (like Maerl) or mineral sources, such as calcium and magnesium; plant ingredients such as liquorice, marshmallow, fenugreek and seaweed; and probiotic or prebiotic ingredients designed to support the intestinal microbiome. Some formulations also include yeast products and nucleotide sources as part of broader digestive support.
What do probiotics and prebiotics do for horses?
Probiotics provide beneficial microorganisms, while prebiotics provide substrates that can support beneficial microorganisms already present in the digestive tract – just as we have described them as the lunchbox. Together, they can form part of a nutritional approach to supporting a diverse and resilient intestinal microbiome. Acid Aid combines probiotic yeast, prebiotic ingredients and high nucleotide yeast as part of its wider digestive support formulation.
What is the role of buffers in digestive supplements?
Buffers can help support a healthy stomach environment by helping to moderate acidity. In Acid Aid, maerl, a calcareous marine algae, provides a natural source of calcium and magnesium that releases gradually and helps maintain a healthy stomach pH. This provides a different approach from simply trying to neutralise stomach acid rapidly.
Can digestive supplements complement a horse's existing diet?
Yes. A digestive supplement can be fed alongside a balanced diet to provide additional nutritional support for the digestive system. Acid Aid is a complementary feed and is intended to be given as part of a balanced diet. The recommended daily amount for a 500 kg horse is 50 g, split between at least two feeds.
Is Acid Aid suitable for everyday digestive support?
Yes. Acid Aid is formulated for daily digestive support, with ingredients selected to support a healthy stomach pH, healthy stomach tissues and wider stomach, intestinal and hindgut health. Its combination of maerl, seaweed, liquorice, fenugreek, marshmallow, milk thistle and probiotic, prebiotic and high nucleotide yeast provides a broad approach to everyday digestive care.
Is Acid Aid suitable for horses experiencing stress, travel or competition?
Acid Aid can be used as part of a daily digestive support routine for horses whose digestive systems may be affected by changes in routine, travel, exercise or competition. The product is specifically recommended for daily support and for those competition and high performance horses and can be incorporated into the horse's normal feeding programme.
