For a horse to perform at its peak, and maintain general health, diet is crucial, says equine veterinarian Dr Ian Church.

You can have the best horse trainer in the world with elite facilities and a world class training regime.

But if you don’t fuel your performance horse with the right diet, it will all be in vain.

Horses have specific dietary requirements that must be tailored to their individual needs.

They require energy, protein, vitamins and minerals and when in heavy work may need up to double the amount of feed.

Ultimately, the goal is to ensure their glycogen levels remain high enough to keep them energised and prevent fatigue.

But where should that energy come from?

Energy sources

Horses derive most of their energy from the glucose in carbohydrates and protein from amino acids.

They do this in one of two ways while some horses, depending on their workload, will use a mixture of both.

Aerobic metabolism – oxygen breaks down carbohydrates, fats and protein into glucose. Endurance horses rely on this type of energy.

Anaerobic metabolism – burns carbohydrates in the absence of oxygen. Energy produced is short-lived and produces lactic acid as a by-product which can build up in muscles, causing fatigue. Quarter horses use this method to gain the power for short bursts.

Their primary source of food should always be forage and preferably fresh.

Forage – the diet staple

Horses ferment the carbohydrates in forage in their hindguts, converting it to energy.

This has the added benefit of keeping their digestive tracts healthy by preventing colic and gastric ulcers.

Better quality forage will typically produce greater energy potential translating to better outcomes.

Oils ain’t oils and hays ain’t hays.

Legume hays are rich in energy and protein and tend to produce better results than grass hays such as orchard grass and timothy.

Alfalfa hay is also a great source of energy, protein, calcium and many other nutrients.

Fresh grass is a horse’s best food source because it exposes them to the sun and fresh air while also keeping them mentally stimulated.

Concentrates – the energy supplement options

While forage will provide most of a horse’s energy requirements, some of the more athletic horses will need additional sources.

There are three main nutrients or supplement options used for digestible energy – carbohydrates, fat and protein.


Cereal grains (oats, corn, barley) are composed mainly of starch and sugar which are two common nonstructural carbohydrates (NSCs).

A horse’s body converts it to energy and either uses it immediately or stores it for later.

Cereal grains like oats can be good for a horse’s digestive health.

But they should be used in moderation as consuming too much at once, particularly in tandem with not enough forage, may lead to hindgut acidosis.

This can cause colic or laminitis (a nasty foot condition) both of which may put a performance horse’s career in jeopardy.

The sugar hit can also produce insulin spikes which may trigger metabolic disorders.


Fat is a more effective and safer way to provide horses with additional energy in heavy work.

That’s because it contains 2.25 times more energy than carbohydrates for its weight.

Fat won’t excite or stimulate horses in the same way carbohydrates do, nor is there any danger of colic or laminitis.

Fat is also cost-effective with vegetable oils, linseed and flaxseed oils, soy hulls and sunflower seeds all relatively inexpensive.

Horses can comfortably consume up to 20% of their diet as fat.

But it is wise to introduce it slowly to keep it palatable and guard against loose stools.

Increasing Vitamin E intake is also advised to prevent the release of cell damaging free radicals.


Protein supplements are not recommended.

Horses normally acquire enough protein from their hay and grass diet, especially if alfalfa is woven into the feed.

Their bodies eliminate excess protein as ammonia in urine which can irritate their respiratory systems as well as their hooves.

High protein diets require a higher volume of water which can leave horses at risk of dehydration and overheating in hot weather.

Ration balancers

If your horse is getting all the energy it needs from forage but is still lacking in some nutrients, ration balancers could be a solution.

They are low-calorie pellets that offer a valuable top up of vitamins and minerals.

Get advice

To ensure the optimum performance and health of your horse, consult an experienced equine veterinarian about specific diet needs.

Dr Ian Church and the Newmarket Equine team provides a dedicated service to the thoroughbred racing industry and is also renowned in Australian polo. We also work with any horse owner or trainer who wants the best for their horse.

Contact us today to book an appointment.


The information contained in this article is general in nature and does not take into account your horse’s individual needs. You should consider whether the information is appropriate to your horse’s needs, and seek professional advice from a qualified vet.



Recommended Posts