We’ve all heard the phrase, “You are what you eat.” It’s a simple yet powerful reminder of how our diet shapes our overall health and well-being. As humans, we have the freedom to choose what we consume, and our food choices directly impact how we feel, look, and how our body functions.
But what about our horses? Do they have the same luxury of choice when it comes to their diet?
In the past, horses roamed freely and grazed on a variety of grass, selecting what their bodies needed based on availability and environmental conditions. This variety helped them maintain a balanced diet and, in turn, supported their gut health. However, in today’s controlled environments, our equine friends no longer have the same luxury of choosing from a diverse range of grasses. As horse owners, we make decisions about what they eat, including selecting the types of forage, concentrates, and supplements they consume. And this is where it becomes interesting: What horses eat directly affects their gut health, and a balanced, diverse microbial population in the gut plays a significant role in their overall well-being.
The Gut Microbiome: A Key Player in Digestion
A horse’s gut microbiome comprises billions of microbes, including bacteria, viruses, fungi, and other microorganisms. These microbes are crucial for the proper digestion and absorption of food, as they help break down complex fibres from grasses and convert them
into beneficial nutrients. It’s important to note that the microbial population in a horse’s gut can vary dramatically depending on what they eat. Even horses with the same genetic makeup can have entirely different microbial populations depending on their diet.
For example, a horse that eats a varied diet with diverse grasses will have a different microbial composition than one fed a high-starch, concentrated feed. This means that the microbes’ growth differs depending on what we feed them. The number of specific bacteria, fungi and viruses is altered depending on what they consume. The presence of specific bacteria, fungi, and viruses can alter how the food is digested and absorbed in the gut. As a result, two genetically similar horses may have very different digestive outcomes due to the varying microbial populations in their intestines.
The Role of Gut Microbes in Colic Prevention
A diverse and healthy microbial population may significantly reduce the risk of colic, a common and often serious digestive disorder in horses. When a horse’s gut microbiome is balanced, it can effectively break down complex fibres and convert them into short-chain fatty acids, which are essential for gut health. These fatty acids help maintain a healthy intestinal lining and promote efficient fermentation in the large intestine.
Fermentation, driven by gut microbes, is vital for proper digestion, particularly of fibrous plant material like grass. The more diverse the microbial population, the more efficient fermentation becomes. A balanced microbiome also helps regulate inflammation, keeping the gut lining intact and acting as a protective barrier against harmful pathogens. When the gut lining is compromised, it can lead to conditions like leaky gut syndrome, infections, or gastrointestinal disturbances.
Additionally, a healthy microbiome can prevent gas buildup and impactions, two common causes of colic. When the fermentation process is balanced, gas production is controlled, reducing the likelihood of painful and dangerous bloating in the gut.
Promoting Healthy Microbial Population
So, how can we promote and maintain a healthy and diverse gut microbiome for our horses? It all starts with their diet.
- We need a healthy microbial population: If you’re concerned that your horse’s gut microbiome is not in optimal condition, you might consider probiotic supplementation. Probiotics are beneficial bacteria that can help restore balance to the microbiome. My personal favourite method for improving gut health is transfaunation, a process where you transfer manure from a healthy horse to one that is suspected of having an unhealthy microbiome. This practice introduces beneficial microbes from a healthy horse into the gut of the horse in need. While this method can be highly effective, it’s essential to consult with your veterinarian to guide you on the scientifically based method of transfaunation.
- Grass as the Main Ingredient: The foundation of any healthy equine diet is high-quality forage, such as grass and pasture. Grass is naturally rich in fibre and supports a diverse microbial population in the gut. By prioritizing forage over concentrates, you help ensure that your horse’s digestive system remains in optimal condition.
- Limit Concentrates: While concentrates (such as grains and pellets) can be useful as a supplement, they should never be the cornerstone of a horse’s diet. Overfeeding high-starch diets can disrupt the balance of gut microbes and contribute to digestive issues like colic. Use concentrates according to your horse’s energy needs and not as a primary feed.
- Reduce Stress: Stress can significantly impact gut health. Horses that experience chronic stress may suffer from digestive disturbances, as stress can alter the balance of their gut microbiome. To help maintain microbial balance, minimise sudden changes in your horse’s environment, provide consistent routines and ensure that your horse has ample opportunities for relaxation and exercise.
- Less is More: A high-quality diet with the appropriate addition of energy-appropriate concentrates should provide all the nutrients your horse needs. Too many “supplements,” which are not always scientifically proven to make a difference, should be avoided, in my opinion. The risk of disturbing the microbial population is much higher than the potential unproven benefit that these products may claim.
Just like humans, horses are deeply affected by what they eat. The health of their gut microbiome determines how efficiently they digest food and absorb nutrients. A diverse and balanced microbial population not only supports healthy digestion but also helps prevent common issues like colic and other gastrointestinal disturbances. By prioritising high-quality forage, limiting concentrates, reducing stress, and considering probiotic interventions, you can help promote a healthy microbiome and improve your horse’s overall well-being.
Ultimately, as horse owners, it’s our responsibility to make informed decisions about what our horses eat. By providing a diet that encourages a healthy and diverse microbial population, we can help ensure that our equine companions remain happy, healthy, and free from digestive issues.
By Dr. Rinel Hugo (LifeCare Veterinary Services)
