Written by: Chris Stafford

Do we truly understand the implications of what we feed horses? HSI takes a look at the latest research into sport horse nutrition.

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Equine nutrition is arguably one of the most thoroughly researched subjects in the management of performance horses and a topic that challenges scientists around the world.

The evolution of equestrian sport, combined with modern demands of elite athletes and commercial pressures, constantly incite horsemen, nutritionists, scientists and feed and supplement manufacturers to produce superior and complex solutions in order to achieve optimum performance.

It may come as a surprise to the younger generation that current research is taking a turn down a road well-trodden and reveals that modern feeding trends are not necessarily the best solution. In fact, we may well be interfering with nature by insulting the horse’s digestive system for our own convenience. The pressure of today’s showing schedules together with the need to travel long distances and across time zones imposes additional stress on the horse that compounds over time.

To some extent one could argue that successful marketing of concentrates and supplements has led us to believe we need to be feeding our competition horses more sophisticated diets, high in protein and carbohydrates. But is that really true? We hear more and more these days of interference to the horse’s hind gut stability and how we should buy this and that to aid digestion. How many cases of ulcers or colic surgeries have you had to deal with, and are they more frequent and life threatening now than they once were? This may be a topic for further exploration but we can begin here by asking if we truly do understand the implications of what we feed horses – whose lifestyles we have changed over the past century.

Management Routines

Not only have we changed their lifestyles, but stable management routines have been modified to suit our lifestyles too. Let’s start with the principles that have been instilled in horsemen over the years; feed little and often; feed at least an hour and a half prior to exercise; feed only the best quality; bulk food is essential for digestion; feed should be offered damp but not wet; feeding is an art based on a horseman’s observation of each animal because no two horses’ requirements are the same. These maxims are the foundation for optimum equine nutrition so it should not be surprising to learn that scientists are guiding us back to these principles and finding that horses have the ability to perform intensive exercise on a high fiber diet.

So are we going full circle and returning to the basics of a simple feeding regime that is based on high quality forage, i.e. hay, and not evolving around concentrates? Horses need a diet that satisfies the natural instincts to chew – a lot. Clearly a stabled horse is removed from his natural environment, which allows him to move around while constantly eating. A need to socialize while eating provides exercise and distraction. A stabled horse, that has not had these basic needs met, can get easily bored. Boredom can lead to behavioral issues, and potentially stress on the digestive system.

These observations have been made by Dr. Jo-Anne Murray, Senior Lecturer at the University of Edinburgh in Scotland. Murray, who is studying the Nutritional Management of Hind Gut Stability, explains that there has previously been little evidence to support the theory that competition horses can perform on a high fiber diet.

Hind Gut Stability

“We are conditioning our horses to be the meal eaters that we are and to fit in with our routine,” she says. Murray recommends feeding three hours prior to exercise because the blood supply should be directed towards the gut to aid digestion, not to exercise. The premise of feeding the best quality forage remains fundamental to healthy nutrition. However, based on her research, Murray presents the notion that cereal grain is not needed for performance horses.

Conversely a paper by A. Jansson and J.E. Lindberg of the Department of Animal Nutrition and Management, at the Swedish University of Agricultural Sciences entitled, ‘A forage-only diet alters the metabolic response in training’, begins with the statement: ‘The high-energy requirements of many performance horses means that supplementation with more energy-dense feeds is necessary and more than 40% of the diet commonly consists of cereal-based, high-starch concentrates (Glade, 1983; Redbo et al., 1998; Williamson et al., 2007).

This is a serious animal welfare issue, as low forage to concentrate ratios and high starch intake are associated with reduced gut microbial stability (Willing et al., 2009), gastrointestinal disorders (Tinker et al., 1997; Hudson et al., 2001; Luthersson et al., 2009) and abnormal and stereotypical behavior (Gillham et al., 1994; Redbo et al., 1998; Waters et al., 2002). In conclusion, Jansson and Lindberg note that their study indicates that a high-energy, forage-only diet alters the metabolic response to exercise and, with the exception of lowered glycogen stores, appears to have positive rather than negative effects on performance traits. N.B. research was based on six Standardbred horses in training.

French Nutrition Findings

Dr. Veronique Julliand, an Equine Researcher at Agrosup Dijon in France is currently leading the research team for “Nutrition du Cheval Athlète,” a project that aims to improve nutritional recommendations for exercise horses. Julliand presented a paper at the Alltech Symposium in Lexington, Kentucky this spring on the ‘Nutrient Requirements and Considerations for High Performance Horses’. It was based on two research projects concerning French trotters in training. Her conclusion is consistent with Murray’s in that performance horses can benefit from a diet that is based on hay representing as much as 90% of their diet. Julliand claims that hay helps to prevent digestive conditions, such as colic, gastric ulcers and other welfare problems. “Horses are herbivores and first of all need hay. It provides water for the hind gut.”

Slow Down on the Fast Food

Dr. Amy Gill, an Equine Nutritionist in Lexington, Kentucky, also enforces the best practice, which is to slow down the feeding and therefore the digestion. The more horses eat like the grazing animal they are, the better it will be for their digestion and therefore their general welfare. While this may not be breaking news, it’s a routine that we have allowed the modern sport horse to drift away from to the detriment of the horse.

We should constantly assess the needs for each horse according to the stage of training and fitness and not be tempted by ‘convenience all-in-one feeds’ – the equine version of our fast food. “Horses are badly equipped from a digestive tract standpoint to metabolize sugar very well and, along with starch, they should be reduced in the diet, not just in the concentrate rations, but also in the forage,” says Dr Gill. “A horse’s digestive physiology is for grazing on low quality forage continuously and they have not evolved out of that so adding the starch and the sugar as a source of calories was a big no-no.” Instead, calories can be provided by very digestible fiber and higher levels of digestible fat, as these are two things that horses can manage very well.

Physiologically Positive

Dr. Gill is currently focusing her work on what is not found naturally in the feed but shouldn’t be added to the feed until just before the horse eats so that the ingredients remain active. These are nutrients that are concentrated in order to produce a physiologically positive effect. They include Omega-3 Fatty Acid, which is a hugely helpful nutrient in that it helps reduce whole body inflammation very effectively. “Horses in training experience a lot of inflammation caused by cortisol in the body, which benefit from a therapeutic level of Omega-3. The oil from the flaxseed is the property that needs to be extracted as this helps control inflammation in the gut, increasing immune response, helping horses recover from hard exercise, increasing oxygen carrying capacity and therefore blood, and to some degree helps in hormone reproduction and levels.”

Healthy Bugs

Other useful nutritional products are equine sourced probiotics, importantly and specifically cultured from the horse’s digestive tract. These are found to be benefitting horses that are undergoing heavy training by maintaining healthy bugs in their digestive tracts. “While probiotics have been around for a while, they were mostly cultured from bovine digestive tracts, which is very different from a horse and therefore not specific to equines,” says Gill. Because of their short life they should be individually packaged and added to the feed immediately before feeding.

Another useful development in equine nutrition is Bio-available Silicon, which has been clinically proven to increase the rate of bone cell production so more bone is laid down where there are insufficiencies, along with collagen production in soft tissues. Skin, hair, hoof, tendon, ligaments and cartilage can be profoundly improved by adding Bio-available Silicon.

Amino Acid Glutamin is a non-essential amino acid which means it does not need to be a part of the diet but can be made by the horse, but at high levels of intense exercise not enough is physiologically generated. Amino Acid Glutamen helps keep the lining of the large colon healthy by ensuring the spaces between the cells are tight so nothing can leak out of the gut. Therefore, without sufficient levels, there can be leakage into the blood stream causing illness.

Gill continues; “A horse should be fed the right type of ingredients at a therapeutic level so it’s necessary to have a scientific understanding of the product; not to be impressed with it having many ingredients on the label as this usually means it does not have a valuable level of any of them.”

Gill advises targeting specific nutrients that are not found in the base program of concentrates and forage. “Establishing a base program for each horse to begin with is essential; this includes calories, vitamins, and minerals.”

In conclusion, once we take a horse from a grazing situation and feed it episodically, e.g. with hay twice a day and large meals of grain three times a day, it inevitably produces horses with metabolic and immune related disorders. We have to find a way to simulate grazing as much as possible and make the horse’s feeding last in order to stimulate its physical and mental health.