Everything Explained Digestive Enhancers

Katie Williams M.Sc. (Dist) R Nutr

You have probably seen advertisements on the TV encouraging you to “top up your friendly bacteria” and may be aware that similar products are available for horses. However, if you’re like the majority of owners you may not be sure whether or not you should be feeding them to your horse and if so, which is the right supplement. What is the difference between a probiotic and a prebiotic?

The role of bacteria in the gut

Mammals are able to produce digestive enzymes to break down nutrients such as carbohydrates or protein but they can’t produce enzymes to break down fibre. Herbivores have evolved to rely on a population of micro-organisms including bacteria, that are able to break down fibre for them, releasing energy and nutrients that the animal can utilise.

Various by-products are produced as a result of fibre digestion including B vitamins such as biotin. The bacteria themselves are also an important part of the immune system and so help to maintain the overall health of the horse. The old adage ‘health comes from within’ really does apply as poor quality hooves, a dull coat and weight loss can all be related to an unhealthy digestive system.

Definitions

The term probiotic is often used to describe products that contain either bacteria or yeast (which is a fungus) as they are both ‘alive’ and have positive effects on the health of the gut.

It is important to understand that there is a difference between the two as they work in different ways and so at Dengie we tend to use the term probiotic to relate to bacteria containing products and yeast to refer to, well… yeast! If you are purchasing a product described as a probiotic make sure you check exactly what it contains and if you are in any doubt contact the company for advice.

In contrast, prebiotics are substances that have an effect on the microbial population in the gut but are not actually live.

Yeast

There are different types of yeast that are added to feeds and supplements. They can be divided into two main categories - live yeast and dead yeast. Live yeasts are often referred to as yeast cultures, which simply means that the medium on which the yeast was grown is also included.

Live yeasts should be approved under EU legislation for use in horses and currently the only approved live yeast is Yea-Sacc1026 which is used in Dengie’s Natural Vitality Digestive Health supplement. To gain approval, evidence supporting the effectiveness, safety and quality of the product has to be provided for different age groups.

The most beneficial effect of feeding live yeast to horses is that it increases fibre digestion, which simply means that a horse should be able to get even more energy from the fibre it eats. If the fibre in the horse’s diet supplies more energy, then it should mean that less concentrates can be fed, which is beneficial for health and behaviour.

This is of particular benefit this year as many hays were harvested very late due to the wet summer and as a result, are less digestible. As the feeding rate for Natural Vitality Digestive Health is only 10 grams per day a 1kg pot lasts 100 days, which means it costs less than 25p a day.

Prebiotics

There are two types of prebiotics commonly used in horse feed - short chain fructo-oligosaccharides (FOS) and mannan-oligosaccharides (MOS). ‘Oligosaccharides’ literally means a ‘few sugars’ and ‘fructo’ and ‘mannan’ indicates where the sugars come from.

The bonds that join FOS together can’t be broken down by the enzymes in the horse’s gut (like fibre) and so the energy they contain is inaccessible to the horse. It is only certain types of beneficial bacteria in the digestive tract that can break FOS down and utilise the energy to thrive and reproduce.

A study presented at the Equine Nutrition Conference in Hannover 2005, investigated the effects of FOS prebiotics in different parts of the digestive tract. The researchers found that horses supplemented with FOS had less acidic digestive tracts than those that weren’t supplemented and suggested that this could help to reduce the risk of problems such as gastric ulcers. Obviously this research would need to be repeated before a definite claim could be made.

Mannan-oligosaccharides originate from yeast cell walls and whereas FOS prebiotics are often referred to as a ‘lunch box’ for specific bacteria, MOS act like sticky sponges that mop-up pathogenic (harmful) bacteria such as E. coli and Salmonella and carry them out of the gut. If harmful bacteria can’t get established in the gut the horse remains healthy. As FOS and MOS work in different ways we include both in our Natural Vitality Senior Vits & Mins supplement to help keep older horses and ponies, who are often most vulnerable to digestive upsets, healthy.

Probiotics

The use of probiotics in horses usually generates considerable debate as there has been little research specific to horses. Preliminary studies to identify the best bacteria to include in an equine probiotic were carried out a few years ago but we are a long way from seeing the findings of these studies being developed and converted to finished products on the market. Current legislation issues also restrict the types of bacteria that can be included in products specifically for horses which is why Dengie only includes Enterococcus faecium in its Natural Vitality Digestive Health Plus supplement.

Which supplement should I use?

This really depends on a number of different factors. Apart from good-doers, all horses would theoretically benefit from being able to get more out of the fibre that they consume as it would mean less cereal based feed could be used, which is good for the horse’s health. Therefore a yeast supplement such as Natural Vitality Digestive Health could be fed to most individuals. Although yeast has to be fed on an on-going basis, it is such good value for money that it is well worth doing, especially when your forage is of poor quality.

Anecdotal reports suggest that FOS prebiotics are useful for those most vulnerable to digestive upsets such as the young and the old, particularly those that get loose droppings.

Like prebiotics, probiotics can be fed long term but can also be used around a potential problem period. As stressful situations are known to disrupt the microbial population it is possible, for example, to use a supplement such as Natural Vitality Digestive Health Plus, which contains probiotics and prebiotics as well as yeast, the day before, the day of and the day after travelling.

Help is at hand

If you have any queries about whether a digestive enhancing supplement may be of benefit to your horse then contact the Dengie feedline on 0845 345 5115 or or email feeds@dengie.com