Perhaps one of the most commonly discussed factors related to equine health is that of the digestive system. A complex organ, the horse’s gastrointestinal tract is made up of a foregut and a hindgut, both of which the horse relies on for normal functioning of the body.
Supporting the hindgut in particular is vital for health, as this is where the majority of digestive processes take place. More and more people are choosing to feed their horses hindgut support supplements, but how do they work, and what benefit do they provide?
The equine hindgut
The equine hindgut (large intestine) is primarily made up of the caecum and colon, and is where most digestion takes place. One of the most important processes that takes place within the hindgut is fermentation, whereby fibre is broken down by microorganisms, and turned into volatile fatty acids (VFAs) – a primary source of energy for the horse.
The group of microorganisms that live in the gastrointestinal tract are known as the microbiota, and include a diverse community of microorganisms such as fungi, parasites, protozoa, and bacteria. You may have heard of the ‘gut microbiome’ before – the microbiome refers to the environment in which these microorganisms reside.
The complex interactions that occur between the microorganisms in the hindgut microbiome mean that it is a very sensitive organ, and can be vulnerable during times of change. Disturbance of the microbiome can lead to common issues such as colic and metabolic syndromes, mostly as a result of an alteration of fermentation patterns. As a direct result, nutrient absorption is decreased, and overall health can be impacted. Research into the equine hindgut is limited compared to that of the human, but what we do know, is that pre and probiotics can provide several benefits to the sensitive ecosystem.
What are probiotics?
Prebiotics and probiotics are not the same, and have different functions within the hindgut.
Probiotics are ingredients that provide the live microorganisms that live in the hindgut. These microbes colonise the digestive tract and help to facilitate functions such as fermentation, digestion, and nutrient absorption. Probiotics also aid immune function, by reducing the numbers of pathogenic bacteria through processes such as antimicrobial production.
As well as providing benefit to the normal function of the hindgut, probiotics are used to provide horses with support when taking medication, recovering from illness, or for improving athletic performance.
The most commonly used probiotics in equine supplements are Saccharomyces cerevisiae, Lactobacillus sp. and Enterococcus sp. There is sufficient research to support the use of all of these, however it has mostly focused on the former. Saccharomyces cerevisiae is a type of live yeast that supports the growth and activity of beneficial bacteria, which improves fibre utilisation and digestibility, thus having a direct impact on general health and energy production.
What are prebiotics?
Prebiotics are types of fibre that provide a food source that is non-digestible to the horse, for the microorganisms living in the hindgut. These compounds help to improve the composition and diversity of the microbiome, in turn improving the function of the microbiota that live there. They are associated with increased fermentation and carbohydrate metabolism, so they play a vital role in overall health and disease prevention.
Prebiotics derived from yeasts, such as mannan-oligosaccharides (MOS) have been shown to reduce the number of pathogens in the hindgut and therefore improve disease resistance and immune function. Other commonly used prebiotics, such as fructo-oligosaccharides (FOS) help to promote the production of beneficial bacteria and reduce disruptions in microbial populations after sudden changes in diet.
Pre and probiotics, whilst different compounds, work synergistically to help support the hindgut microbiome. Think of the probiotics as the workers, and the prebiotics as their meals. One could not exist without the other, and both play a vital role in promoting overall health by supporting normal function of the hindgut.
When to feed them
Ultimately, all horses will benefit from being given pre and probiotics, but, some will need them more than others. There are several times that you may consider feeding them, such as:
- During transitions – such as change of diet, travelling, stress
- After antibiotic treatment
- After worming
- For horses with a history of gastro-intestinal issues
- For poor-doers or horses that lose condition at any time of year
There is a huge range of gut support supplements available on the market, so it is important to ensure that you are choosing the right one. Make sure to take note of what types of pre and probiotics are contained, at what levels they are included, and whether the company follows feed safety regulations such as UFAS and BETA NOPS.
Science Supplements Gut Balancer provides the highest levels of research-proven pre and probiotics, to provide the best support possible and promote the healthy function of the hindgut.
Take away
The equine hindgut microbiome is a complex system that must be carefully considered when making management decisions for horses. While supporting the microbiome can significantly influence overall health, it’s essential to recognise that prebiotics and probiotics are not cure-alls. Instead, they should be used in combination with balanced nutrition and good management practices.
Written by Anna Jones BSc (Hons) Equine Science - Customer Service Advisor
References
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