By Shelagh Niblock, PAS

Horse owners know how important good nutrition is to the health and performance of their animals. They spend considerable time and money ensuring that their horses are provided with the nutrition they need to do a job and stay healthy. There is a great deal of debate in the equine industry today about feed and its safety or suitability for our horses. We search the internet seeking the best supplements, and more and more we are backing up our research with lab analyses to ensure we know as accurately as possible just what we feed them. Despite this diligence on the part of horse owners there can still be issues with health and performance. Horses who are working intensely are subject to gastric ulcers and hindgut upset. Performance horses can “hit the wall” and run out of energy when they most need it to be successful. Why does this happen and what can we do to feed our horses better?

Mealtimes Matter

The timing of meals for working horses is a poorly understood and easily overlooked subject. We know that, in general, horses have a small stomach and so the practice of feeding small meals frequently is preferable to large meals, especially when feeding concentrates like grains. We also know that horses can be prone to gastric ulcers, especially if they are on an intensive work or training schedule. It’s also generally well known that horses secrete gastric acids in their stomachs constantly and not just in response to a meal. The potential outcome of this digestive adaptation is discomfort for a horse performing on an empty stomach. So how, exactly, does the timing of meals affect your horse’s health and performance?

Meals of concentrates fed prior to performance events can negatively impact the horse’s ability to perform. Photo: Shutterstock/Sharon Kingston

Feeding for Foregut Health

One of the most effective ways to ensure a healthy foregut for your horse is to feed consistent small meals of forage throughout the day. No matter what your horse’s need for supplemental energy provided by concentrates, all horses need access to consistent intake of palatable forage. Grass hay works well, as do grass-alfalfa mix hays. Alfalfa itself is an excellent buffer in the stomach of the horse, largely due to its bulky fibre content and the high level of calcium it contains. Straight alfalfa must be fed with caution, though, due to its high protein content. Protein fed in excess of needs has to be metabolized and excreted, a metabolic process that costs your horse energy. Soaked alfalfa pellets and cubes can be a good alternative to provide an effective stomach buffer for your horse prior to working.

Although one would think that a diet of free-choice hay offered every day would suit all horses and give them good gastrointestinal tract health, that isn’t the case with all horses. Some horses, in particular those that are insulin resistant (IR) or diagnosed with equine metabolic syndrome (EMS), must have some kind of control on their feed intake. These are the kind of horses that are ALWAYS hungry and will never say no to feed. Too much feed isn’t good for the health of any horse, or for their performance.

Feeding for Hindgut Health

Feeding a consistent diet of small, frequent meals of good quality forage is an excellent start to a regime to maximize gastrointestinal health. Not only does it ensure the stomach generally has a small amount of forage in it to help buffer the gastric juices secreted, it also means that the hindgut or cecum and large colon also have a consistent supply of high quality complex carbohydrates. This helps ensure a balanced hindgut pH, and consequently a healthy population of hindgut microbes. Good “bugs” ensure that adequate safe energy is being provided to the horse from the fermentation of complex carbohydrates to volatile fatty acids (VFA), a safe energy source for all horses. Good bugs also reduce the risk of hindgut upset including chronic diarrhea, gas colic, and potential laminitic changes in the horse’s feet.

Immediately after work, provide good quality hay, water, and electrolytes if needed. Concentrates can be fed after three or more hours. Photo: Clix Photography

Water, Forage and the Performance Horse  

Another lesser known aspect of a hindgut full of good hay is the water-carrying capacity it offers. The partially-digested hay in the hindgut acts like a giant sponge that can hold water, which is potentially available metabolically to your horse at any given time. Research has shown that different kinds and maturities of hays have varying abilities to actually carry and provide water for metabolic use for the horse. Grass hays have a great capacity to hold water in the hindgut of the horse, and as the fibre is utilized in the fermentation process by the microbes, the water is released and available for use metabolically by the horse. Beet pulp, alfalfa hay, and forage cubes, as well as some commercial high-fibre concentrates, also have great water-carrying capacities as well as excellent capacity for releasing water into the lumen of the digestive tract for use by the horse when needed.

Does Timing of Grain Meals Affect the Performance Horse?

In general, small meals of forage like hay, fed often, are not only safe but advisable for performance horses. The timing of meals of concentrates like grain prior to performance events, though, can have a significant impact on the animal’s ability to perform no matter what his conditioning.

Meals that are high in sugars and starch are rapidly converted to glucose in the stomach and small intestine of the horse. The glucose is absorbed through the gut wall into the bloodstream, and the increase in blood glucose elicits a corresponding increase in insulin secreted by the pancreas. The insulin facilitates the movement of the glucose into the tissues where it is stored as glycogen or fatty acids. Blood insulin levels after eating starchy meals are at their highest about two to three hours after feeding. Research has shown that this can have significant effects on the ability of the performance horse to utilize free fatty acids and glucose available in the tissues and bloodstream.

Partially-digested hay in the hindgut acts like a sponge to hold water, which is available to the horse at any given time. Photo: iStock/Gabriele Grassl

Aerobic exercise refers to cell metabolism in the presence of oxygen, and in horses includes activities of a longer duration such as endurance or dressage. Aerobic exercise is largely accomplished through the oxidation of fuel sources. Efficient aerobic exercise relies on good cardiovascular fitness to continue to supply the cell with oxygen and a good supply of circulating fuel such as glucose and fatty acids. High levels of circulating insulin result in glucose being moved into the tissues for storage at the same time the requirement for them for energy for work is at the highest. This can drop the blood glucose down rapidly, causing fatigue and the experience of your horse “hitting the wall.” High blood insulin levels can also “put the brakes on” body fat mobilization, thereby reducing the amount of fatty acids circulating in the blood for fuel.

Anaerobic exercise refers to cell metabolism that takes place in the absence of oxygen. This would include speed work like jumping, racing, eventing, and barrel racing. Good cardiovascular fitness is important in anaerobic metabolism because it facilitates the removal from the muscle cell of waste products, like lactic acid, which can accumulate during anaerobic metabolism. Most of the work our horses perform relies on a combination of anaerobic and aerobic energy metabolism.

A very common practice is to give our horses a meal prior to transport to the show or performance event, and if you do the math you will see that it isn’t unusual to have our horses working hard within two to three hours of a meal of starch. That high energy meal fed on the morning of the event could be the reason your horse fatigues more quickly than you were experiencing at home or in training. Timing of high energy meals is very important to maximize the energy benefit derived from them.

What About Feeding After Exercise?

Performance horses need to be allowed to “refuel” their muscles after a hard work event, but in general it is advisable to feed hay only for at least two hours after hard work. Small meals of concentrate can be offered after that time. Electrolytes may also be provided, and water should always be available.

Whether at home or at the show, nothing beats small meals of good quality forage fed often, and regular access to fresh water. Photo: iStock/Magbug

Recommendations

In general, it is always advisable to feed our horses small but regular meals of a good quality forage. Well-timed forage meals do not have the same effect on the glucose/insulin metabolic process that many concentrates do, and will also help prevent boredom and stress-related issues like gastric ulcers. Small meals of good quality forage will also help your horse carry adequate water in his hindgut. Adequate water for the performance horse is critical for hindgut health and healthy metabolism.

Avoid feeding high starch, sugar, and/or fat meals on the morning of the performance event or within three hours of performance. For best results, high energy meals like grain or fat sources should be fed the night before the competition. Care immediately after performance should include good quality hay, water, and possibly electrolytes, with concentrates being reserved for feeding three hours or later after the work.

If your performance horse “hits the wall” and runs out of energy when he needs it most, the timing of his feeds could be a factor. Photo: Dreamstime/Amy Mitchell

Conclusions

Whether you live for an active performance schedule, or prefer to head out to the local schooling show, or enjoy a long leisurely ride down the trail, it’s a good plan to feed concentrates as far in advance of work as you can. For most competitors that means grain feeding at night. But whatever your riding pleasure, remember that for optimum horse health and performance, nothing beats regular small meals and a good quality forage. It’s hard to go wrong with good hay for horses. 

Main article photo: Shutterstock/Kento35