The Foundations of Equine Nutrition
Feeding a horse correctly is both simpler and more complex than many new owners expect. Simpler, because the basic principle is straightforward: horses are herbivores designed to eat large quantities of fibrous plant material throughout the day. More complex, because the devil lies in the detail — hay quality, individual variation, workload, age, health status, and the specific mineral profile of your region all interact to determine what your horse truly needs. Getting nutrition right is one of the most powerful things you can do for your horse's long-term health, soundness, and performance.
Forage First: The Non-Negotiable Principle
The forage-first principle is the cornerstone of equine feeding. Horses evolved to spend 14 to 16 hours per day grazing, consuming fibrous plant material that is fermented in the hindgut by a vast community of microorganisms. This system is delicate — disrupting it by providing insufficient forage or feeding large quantities of starch-rich hard feed is a leading cause of colic, gastric ulcers, laminitis, and stereotypic behaviours such as crib-biting and weaving.
As a minimum, horses should receive at least 1.5 per cent of their bodyweight in forage dry matter daily. For a 500 kg horse, this equates to approximately 7.5 kg of dry matter per day. Many horses in light work can meet all their energy requirements from forage alone — additional hard feed is only justified when the horse genuinely cannot maintain condition on forage, or when the energy demands of intense work cannot be met by hay or pasture alone.
Where possible, allow ad libitum access to hay or haylage, particularly during the winter months. Restricting forage for extended periods increases stress, the risk of gastric ulcers (horses produce stomach acid continuously, whether or not they are eating), and the development of behavioural problems. If weight management is a concern, use a small-holed hay net to slow consumption rather than eliminating forage.
Hay Quality and Testing in the EU
Not all hay is equal. Quality varies enormously depending on the grass species present, the stage of growth at cutting, weather conditions during harvest, and storage. In general, hay cut at early to mid-flowering stage has a better balance of digestible energy and protein than late-cut hay, which is more mature and stemmy. Haylage — partially wilted and fermented grass — has a higher moisture content and is often more palatable and digestible, but must be produced and stored correctly to avoid harmful fermentation and mould.
Hay analysis is strongly recommended, particularly if you are buying in bulk or if your horse is in a specific physiological state — in training, pregnant, lactating, or elderly. Laboratories in the UK, Germany, France, and other EU countries offer equine hay analysis panels that report on digestible energy, protein, sugar and starch content (important for laminitis-prone horses), and mineral levels. The results allow you to identify deficiencies and excesses and tailor supplementation accordingly, rather than guessing.
Hard Feeds: When Are Concentrates Needed?
Hard feeds — compound mixes, nuts, cubes, or straights such as oats, barley, and sugar beet — are energy-dense feeds intended to supplement forage when additional calories or nutrients are needed. They are not required for every horse. The temptation to feed generous amounts of hard feed because it feels like a positive action is one of the most common nutritional mistakes horse owners make.
Candidates for hard feed supplementation include horses in medium to hard work whose energy needs cannot be met by forage alone, broodmares in late pregnancy and early lactation, foals and young growing horses, and underweight or elderly horses with reduced ability to digest forage efficiently. When hard feed is required, choose a product designed for your horse's specific life stage and workload, and always prioritise high-fibre, low-starch options to support hindgut health.
EU feed regulations, specifically EC Regulation 767/2009 on the placing on the market and use of feed, set out the labelling requirements for animal feeds sold in Europe. This regulation requires manufacturers to declare analytical constituents including protein, fat, crude fibre, and ash content, as well as additives present above certain thresholds. Familiarise yourself with feed labels — a product with a high sugar and starch content is not appropriate for an easy keeper or a horse prone to laminitis, regardless of how it is marketed.
Common Nutritional Deficiencies in European Horses
Selenium
Selenium deficiency is one of the most widespread nutritional problems in horses across Northern and Western Europe. Soils in the UK, Ireland, Germany, Scandinavia, and parts of France are naturally selenium-poor, meaning that grass and hay grown on these soils contains insufficient selenium for horses. Selenium is essential for muscle function, immune response, and reproductive health. Deficiency can cause white muscle disease in foals, tying-up (exertional rhabdomyolysis) in adult horses, and reduced fertility.
However, selenium has a narrow therapeutic window — the gap between a deficient dose and a toxic dose is small. Never supplement selenium without first establishing the horse's current selenium status through a blood test. Supplementation should be guided by your vet and based on laboratory results. Many compound feeds sold in selenium-deficient regions already contain added selenium — adding a separate selenium supplement on top can easily cause toxicity.
Vitamin E
Vitamin E works synergistically with selenium as an antioxidant. Fresh grass is an excellent natural source, but horses relying heavily on hay — particularly hay that has been stored for more than three to six months — may receive inadequate Vitamin E. Deficiency is associated with equine motor neurone disease, equine degenerative myeloencephalopathy, and poor immune function. Horses in hard work, older horses, and those with limited access to fresh pasture are most at risk. Natural Vitamin E (d-alpha-tocopherol) is significantly better absorbed than synthetic forms (dl-alpha-tocopherol) and should be the preferred supplement form.
Iodine
Iodine deficiency and excess are both recognised problems in some European regions. Iodine is essential for thyroid function, and deficiency can cause goitre, poor growth, and reproductive failure. Excess iodine — often introduced through over-supplementation or the feeding of seaweed-based products — can cause identical signs. Have your horse's iodine status checked before supplementing, and be cautious with products that contain kelp or seaweed, which can deliver very high and unpredictable iodine loads.
Salt and Mineral Licks
Sodium chloride (salt) is an essential nutrient that horses lose through sweat. A plain white salt block available at all times allows horses to self-regulate their intake. Alternatively, loose salt can be added to the feed at a rate of approximately 10 g per day for horses in light work, increasing with sweat loss during exercise or hot weather.
Mineral licks — often referred to as salt licks — come in many formulations beyond plain salt. Himalayan salt blocks, trace mineral blocks, and compound licks are widely marketed. The value of these products depends entirely on the specific minerals included and whether your horse actually needs them. A plain salt block is universally beneficial. More complex mineral licks should only be used if a genuine deficiency has been identified, as they risk delivering excessive levels of certain trace minerals.
Water Requirements
Water is the most important nutrient of all. An adult horse at rest typically drinks 25 to 45 litres per day. This rises substantially — to 60 litres or more — in hot weather, after exercise, or when feeding dry hay rather than fresh grass or haylage. Horses that do not drink adequately are at significant risk of impaction colic. Ensure clean, fresh water is always available. Check water sources daily; horses will often refuse to drink from contaminated, algae-covered, or frozen troughs.
Weight Management and Body Condition Scoring
Obesity is one of the most significant welfare and health problems in horses and ponies across Europe, strongly associated with laminitis, insulin dysregulation, and equine metabolic syndrome. Conversely, horses that are too thin are at risk from a range of health and welfare problems. Body condition scoring (BCS) is the standard method for objectively assessing a horse's nutritional status.
The Henneke Body Condition Scoring system, developed in 1983 and widely used across Europe and North America, assesses fat deposition at six key sites: along the neck, at the withers, behind the shoulder, over the ribs, at the loins, and around the tailhead. Scores range from 1 (extremely thin) to 9 (extremely fat). An ideal score for most horses is between 4.5 and 6, with performance horses often maintained at the lower end of this range.
Assess your horse's BCS monthly. Do not rely on visual assessment alone — run your hands firmly over the ribs and key scoring areas, as a thick winter coat or muscle development can be deceptive. Adjust feeding accordingly, reducing calorie intake for horses trending above 6 and increasing it for those dropping below 4.5.
Supplements: When Are They Necessary?
The equine supplement market is enormous and largely unregulated in terms of efficacy claims. While some supplements are genuinely useful in specific circumstances, the majority of horses on a well-balanced diet with good-quality forage do not need supplementation beyond a broad-spectrum vitamin and mineral balancer.
Before purchasing any supplement, ask the following questions: Has a deficiency been confirmed by blood test or forage analysis? Is there peer-reviewed evidence that this product addresses the problem? Does the dose provided in the recommended serving deliver an effective amount of the active ingredient?
Joint supplements, gastric support products, calming supplements, and coat conditioners are among the most heavily marketed categories. Some contain ingredients with reasonable evidence bases at appropriate doses; many do not. Work with an equine nutritionist or your vet to identify genuine nutritional gaps in your horse's diet before spending money on supplements that may deliver little benefit.