NUTRITION OF THE PERFORMANCE HORSE

Hayley Parker MA VetMB CertAVP MRCVS, Clinical Director and Equine Vet, Kingston Equine Vets

With the competition season gradually creeping up on us as the days get longer, many horse owners and equine professionals are busily getting their four-legged athletes fit particularly if they’ve had the winter off rather than enjoying the fine hedge-hopping opportunities which Dorset’s hunting scene offers. Strict and well-structured exercise regimes will have been created but how many are thinking hard about the nutritional aspect? Accurately assessing the level of work performed by a horse is essential in determining the amount and type of feed offered.

Energy is produced by aerobic or anaerobic metabolism. The breakdown of carbohydrates, fats, and protein into energy with the involvement of oxygen is an aerobic reaction. Because oxygen is required, this energy-producing process is slow. The conversion of glucose or glycogen to lactic acid does not require oxygen and is therefore an anaerobic reaction, a process that produces energy quickly.

High-intensity, short-duration exercise

Quick acceleration and top speed over a short distance require anaerobic energy. Examples of high-intensity, short-duration work are thoroughbred, arab and pony racing (particularly over sprint distances) and some western riding competitions such as barrel racing. Traditional carbohydrate-heavy feeds, which include most low-fat concentrates, and forage may satisfy the nutritional requirements of these athletes. The digestion of carbohydrates provides muscles with glycogen, a fuel critical for high-intensity performance. As workload increases and energy reserves empty, large quantities of complex carbohydrates may be offered to the horse in order to maintain body condition. However, high carbohydrate diets increase the risk of colic, gastric ulcer syndrome, laminitis and metabolic disorders so replacing a fraction of the carbohydrate content with energy-rich fat is one way to reduce these risks.

Horses fed high-fat rations typically require lower quantities of feed to satisfy requirements because fat delivers 2.25 times the energy of an equal amount of carbohydrate. Protein can also be used as an alternative energy source but be aware that research has proven that feeds too rich in protein may negatively affect performance.

Moderate-intensity, medium-duration exercise

This type of athlete undergoes exercise that taxes but doesn’t exhaust and requires aerobic and anaerobic energy production. Primarily, moderate-intensity, medium-duration work involves intensive sport horse training and competition.

Feeds formulated for horses performing at moderateintensity, medium-duration work should be similar to those fed horses involved in high-intensity, short-duration performance. One primary difference, however, involves feeding management. Horses in this classification may require less feed to support the work effort.

Low-intensity, long-duration exercise

This work includes endurance activities that typically last two or more hours. Aerobic energy production is required to sustain this type of exercise.

As workouts become longer, high-quality forage becomes more imperative in the diet. Not only is fibre a source of energy, but it holds water and electrolytes in the hindgut. Horses can draw on these reserves during exercise, effectively suppressing dehydration. In particular, beet pulp and soybean hulls are considered ‘super fibres’ because of their high bacterial fermentation rate and water-holding capacity.

Not all equine competition fits neatly into one of these classifications. Some activities mesh properties of more than one. With its long twisting courses and explosive jumping efforts, show jumping, for instance, represents both high- and moderate-intensity activity, as does the cross-country phase of eventing where the elitelevel eventers are required to complete high-intensity activity for longer. Polo, a fast-paced sport of sudden accelerations and abrupt stops mixed with easy canters and full-tilt gallops, combines all three exercise classes.

The take-home message here is to always feed your horse for their work, taking into account duration, frequency and type of exercise. Make sure that you consider that however fit and well-trained your horse is, they need the appropriate amount and type of food to complete the task asked of them. And do not hesitate to consult a qualified equine nutritionist or equine vet to assist in the creation of your equine athlete’s optimum diet.

kingstonvets.co.uk