Performance Horse Fuel

Performance Horse Fuel

Another very interesting topic at the KER conference in Florida was presented by Dr Joe Pagan, it looked at the different energy sources that horses can use to fuel performance.

Locomotion of any animal requires the muscles to contract, for contraction to take place the muscle needs fuel in the form of ATP (adenosine triphosphate).

The horse has a number of ‘fuel’ sources available to the muscle to create ATP:

Fat – Horses can burn fat aerobically to create ATP. It is plentiful in the horse as stored throughout the body, however it is a slow fuel and not the first choice if the horse needs to generate ATP more quickly. In the diet fat is most commonly provided by vegetable oil, this is calorie dense and horses digest it well.

Sugar and Starch – Non structural carbohydrates. Cereal grains provide a good source of starch. Via enzymatic digestion horses break down starch and sugars to glucose, glucose is then taken into the bloodstream, it can oxidized at that time to produce ATP or converted to glycogen and stored in the muscle or liver.

Plant Fibre – The fermentation of fibre in the hindgut of the horse generates volatile fatty acids (VFAs). The horse can then absorb the VFAs and produce fatty caids and glucose.

Protein – this is not typically used as an energy source. It is inefficient and in most instances an expensive source of calories. Extreme excesses of protein in the diet is not desirable.

All these energy sources can be used by the horses muscles to fuel contraction. However a number of factors may influence the best fuel source to be used depending on discipline, breed, temperament, desired body condition and energy level expended by the horse (determined by a combination of exercise, intensity and duration).

Dr Pagan discussed the difference between breeds focusing on Thoroughbreds and Arabians, these two breeds have different muscle composition and therefore their muscles have different preferences in the fuel they chose to use to generate muscle contraction. A study he carried out many years earlier compared the two breeds. Under the same feed and work conditions the arabians burned more fat, preferentially choosing fat as their fuel. In contrast in the faster work the thoroughbreds produced more lactic acid an indicator of anaerobic metabolism, they had called on muscle cells that relied on glucose for their fuel.

Dr Pagan said if we have a continuum with the two breeds, Arabian endurance horses at one end with the requirements for fat and fibre and less dependency on NSC and thoroughbred racehorses at the other end, most other horses will find a place within this continuum.

The key take out from this presentation for me was that the feed sources chosen to fuel locomotion in the equine equine athlete will depend on the type of work, intensity of that work and the breed. Low-intensity exercise should skew toward low-starch, high-fat feeds, high-intensity, short-duration work should toward a more NSC and lower fat feed.

This may not only influence feed formulation but also the total make up of the horses daily ration. As always temperament can’t be overlooked and any ailments or preexisting conditions that may influence feed choices.