Feeding Hay to Horses: Types, Quality and How Much to Feed

Reviewed by Dr. Ali Ehtisham, DVM

Hay is the foundation of virtually every domesticated horse's diet. For horses without access to sufficient pasture — which includes most horses in full-time stable management, horses kept in dry lots, and horses whose grazing is restricted for health reasons — hay is the primary and often the only forage source. Getting it right is not complicated, but the differences between hay types, quality grades, and feeding quantities matter enormously for health, weight management, and digestive wellbeing.

Horses evolved as trickle-feeding grazing animals, designed to process small amounts of fibrous plant material almost continuously. A horse's digestive system is built for near-constant gut motility, driven by the steady flow of forage. When forage access is restricted — whether by rationing, unsuitable management, or insufficient hay — gastric ulcer risk rises, stereotypic behaviours such as crib-biting and box-walking emerge, and hindgut health deteriorates. Horses should have access to forage for a minimum of 16–18 hours daily; the goal is always to mimic the grazing pattern as closely as practical.

Types of Hay

Meadow Hay

Meadow hay is cut from permanent pasture — land that has not been ploughed and reseeded, but rather maintains a natural community of grass species, broad-leaved plants, and herbs that has established over many years. The species mix typically includes fescues, bents, ryegrass at lower proportions than in sown leys, plantain, yarrow, and various other meadow plants depending on soil type and location.

This botanical diversity gives meadow hay its nutritional character. It is generally lower in non-structural carbohydrates (NSC — sugars and starches) than ryegrass-dominant hay, and it is often more suitable for native breeds, ponies, cobs, and easy keepers who are prone to weight gain or laminitis. The palatability is typically very high — horses find the mix of flavours and textures appealing — and many owners find their horses prefer a good meadow hay to a pure ryegrass hay.

The significant caveat is variability. Meadow hay quality depends enormously on the specific field, its fertility, the timing of cutting, the weather during drying, and handling in storage. A well-managed, timely-cut meadow hay from good land can be an excellent choice; a late-cut, over-weathered meadow hay from neglected pasture may have very poor nutritional value and high mould risk.

Seed Hay — Ryegrass Hay

Seed hay is cut from sown leys — fields seeded with specific high-yielding grass varieties, predominantly perennial ryegrass (Lolium perenne). Ryegrass is selected for its high yield and nutritional density: it is higher in digestible energy and typically higher in NSC than the mixed species in meadow hay.

This makes ryegrass hay more appropriate for horses with higher energy demands — Thoroughbreds, poor-doers, horses in hard work, and broodmares — but potentially too rich for native breeds, overweight horses, or laminitis-prone individuals. The higher NSC content that gives ryegrass hay its energy density is precisely the feature that makes it inappropriate as the primary forage for metabolically sensitive horses. If you keep a mixed yard with horses of varying calorie demands, consider sourcing different hay types for different horses rather than using the same hay for all.

Timothy Hay

Timothy (Phleum pratense) is a species widely grown in North America and increasingly available in Europe. It is typically lower in NSC than ryegrass hay and has a reputation for high palatability and good digestibility. It is popular in North America as a standard horse hay and is often the default choice for horses with gastric issues or digestive sensitivities. The relatively consistent quality of purpose-grown Timothy makes it a reliable choice. It is generally less calorific than ryegrass hay and more suitable for easy keepers and horses with metabolic concerns.

Alfalfa (Lucerne) Hay

Alfalfa is a legume rather than a grass, and its nutritional profile is fundamentally different from any grass hay. It is exceptionally high in protein (15–22% crude protein), calcium, and digestible energy. It is not a grass hay substitute for the majority of horses — its calcium-to-phosphorus ratio, high protein, and very high calorie density make it unsuitable as a primary forage for easy keepers, ponies, or leisure horses in light work.

However, alfalfa is genuinely valuable in specific circumstances. Broodmares in late pregnancy and lactation have dramatically elevated protein and calcium demands. Growing youngstock need high-quality protein for muscle and bone development. Horses in very hard work or horses that are genuinely underweight benefit from alfalfa's calorie density. In these situations, incorporating alfalfa as a portion of the forage ration — perhaps one-third of daily forage intake — is a practical and effective strategy.

Haylage

Haylage is an increasingly popular alternative or supplement to hay. It is conserved at a higher moisture content — typically 35–50% moisture, compared to hay's 15–20% — in wrapped bales, where the anaerobic conditions promote fermentation that preserves the forage. The result is a product that is lower in respirable dust and fungal spores than dry hay, making it particularly suitable for horses with equine asthma (recurrent airway obstruction, formerly called RAO or COPD) or other respiratory sensitivities.

Haylage has a higher calorie density per kilogram of fresh weight than hay, because the fermentation process increases the energy availability of the forage. This means horses are typically fed somewhat less haylage by weight than hay for an equivalent energy intake, though dry matter comparisons are essential for accurate rationing. Once a haylage bale is opened, it is exposed to oxygen and begins to deteriorate: unused portions should be discarded after a few days rather than allowing the horse to eat progressively deteriorating forage. Haylage does not need to be soaked.

Assessing Hay Quality

Visual and Sensory Assessment

Good hay is green, leafy, and sweet-smelling. The green colour indicates that the hay was cut at an appropriate stage of grass growth and dried without excessive weathering — the chlorophyll that gives fresh grass its colour is preserved. Yellowing or bleaching indicates that the hay was left in the field too long, rained on during drying, or stored improperly, all of which reduce nutritional value.

The smell is equally informative. Good hay smells sweet and fresh. Mouldy hay has a musty or earthy smell. Hay that smells sour or fermented may have been baled at too high a moisture content. Never feed mouldy hay — mould spores cause respiratory disease when inhaled during eating and handling, and some mould species produce mycotoxins capable of causing colic, liver damage, and neurological signs.

The structure of the hay tells you about cutting timing. Leafy hay with fine stems was cut early, when grass nutritional quality was high. Coarse, stemmy hay with abundant seed heads was cut late — lower protein, higher fibre, lower overall nutritional value.

Laboratory Analysis

For horses with metabolic conditions — laminitis, equine metabolic syndrome, Cushing's disease — subjective assessment is not sufficient. The non-structural carbohydrate content of hay needs to be below approximately 10% (dry matter basis) for these horses, and this cannot be reliably estimated visually. Laboratory analysis of a hay sample is available from specialist equine feed analysis services at modest cost, and is strongly recommended when purchasing hay in quantity for any horse requiring NSC restriction. The analysis also provides crude protein, energy (digestible energy or megajoules of metabolisable energy), and fibre parameters — all useful for precision rationing.

How Much Hay to Feed

The minimum daily forage requirement is 1.5% of bodyweight as dry matter. For a 500 kg horse this is 7.5 kg of dry matter from forage daily — this is the floor, not the recommended amount. A more appropriate general target is 2% of bodyweight: approximately 10 kg of hay per day for a 500 kg horse.

This should be adjusted based on body condition score. A horse maintaining weight and good condition on a hay-based diet does not need more — but neither should forage be restricted below the 1.5% floor without specific veterinary guidance, as doing so compromises digestive health and increases ulcer and stereotypy risk. Horses in hard work will require either more hay, higher-energy hay, or supplementary hard feed to meet elevated energy demands. Poor-doers may need haylage, alfalfa inclusion, or additional hard feed.

Multiple feeding points prevent competition in group-housed horses and reduce feeding-related stress. Small-holed hay nets extend eating time and better mimic natural grazing behaviour — a horse eating from a small-holed net takes longer to consume the same amount of hay, keeping the gut occupied for more hours of the day.

Soaking Hay

Soaking hay in water before feeding reduces its NSC content and is used for horses requiring sugar restriction. A 30-minute cold soak reduces NSC by approximately 25–30%. A longer soak (60 minutes), warm water, or both increase the reduction further, though the gains diminish with time and temperature. Soaking increases the bacterial count in the hay and adds substantial weight (waterlogged hay is heavy), and the soaking water — now rich in leached sugars and nutrients — should be disposed of thoughtfully to avoid encouraging vegetation overgrowth or polluting drainage.

Soaking is not appropriate for all horses. Horses in hard work, horses that are already difficult to maintain in good condition, or horses with no metabolic concerns lose nutritional value from their forage without any benefit. For dust-sensitive horses who do not require NSC restriction, haylage or steamed hay is a better choice than soaking.

Frequently Asked Questions

What is the difference between hay and haylage?

Hay is dried to approximately 15–20% moisture and stored dry. Haylage is conserved at 35–50% moisture in wrapped airtight bales, preserved by fermentation. Haylage is lower in dust, higher in calorie density per kg, and perishable once opened. It does not require soaking.

Should I soak hay for my horse?

Soaking is appropriate for horses requiring NSC restriction (laminitis, metabolic syndrome, Cushing's disease) or horses with severe dust allergies. It reduces NSC by 25–50% but also increases bacterial count and reduces nutrients. Not appropriate for horses in hard work or those without metabolic concerns.

How much hay does a horse need per day?

A minimum of 1.5% of bodyweight as dry matter — approximately 7.5 kg of hay for a 500 kg horse. The more typical target is 2% bodyweight, or around 10 kg of hay daily. Adjust based on body condition, work level, and whether additional feed sources are provided.

Is alfalfa hay safe for horses?

Yes, when used appropriately — as a supplementary forage, not the sole forage. Alfalfa is very high in protein, calcium, and energy: ideal for broodmares, youngstock, and horses in hard work, but too rich for native breeds, easy keepers, or laminitis-prone horses when fed as the primary forage.

How do I know if hay is good quality?

Good hay is green, leafy, sweet-smelling, and free from mould or excessive seed heads. For horses requiring NSC restriction, laboratory analysis is the only reliable way to know the sugar content. Never feed hay that smells mouldy or musty.

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Disclaimer: This article is for educational purposes only and does not constitute veterinary advice. Always consult a licensed equine veterinarian for diagnosis and treatment.