How to Choose Safe, High-Quality Hay for Your Horse

By Dr Duncan Houston

Hay can look green, smell pleasant and still be completely wrong for the horse eating it.

A leafy, calorie-dense alfalfa may be excellent for a lactating mare but excessive for an overweight pony. A mature grass hay may look less impressive but be ideal for an easy keeper. Meanwhile, any hay that is mouldy, excessively dusty or contaminated can be unsafe regardless of its nutritional value.

The best hay is not necessarily the richest hay. It is hay that is clean, palatable, nutritionally appropriate and safe for that individual horse.

Quick Answer

Choose hay based on your horse’s body condition, workload, age and health rather than colour or species alone.

Inspect several opened bales for maturity, leaf content, softness, smell, dust, moisture, mould, weeds and foreign material. Forage analysis is the only reliable way to determine energy, protein, sugar, starch and mineral content.

Do not feed visibly mouldy, musty, contaminated or unusually hot hay. Introduce every new batch gradually, even when it is supposedly the same type of hay. (University of Minnesota Extension)

What Makes Hay High Quality?

Hay quality has three separate components.

Measure of quality	What it means
Nutritional quality	Energy, protein, fibre, sugar, starch and mineral content
Hygienic quality	Amount of mould, dust, bacteria, weeds, insects and contamination
Suitability	Whether the hay matches the needs of the horse eating it

A hay can score well in one category and poorly in another.

For example:

• Leafy alfalfa may have excellent nutritional value but provide too many calories for an obese horse.

• Mature grass hay may suit an easy keeper but be inadequate for a lactating mare.

• A visually attractive bale may still contain respirable dust or mould spores.

• Low-sugar hay may be metabolically appropriate but too coarse for a senior with poor teeth.

AAEP guidance similarly separates the nutritional value of hay from its hygienic quality, because both must be considered before hay can genuinely be called good. (AAEP)

The Most Important Factor: Plant Maturity at Harvest

Plant maturity is one of the strongest predictors of hay’s nutritional value.

Young plants generally contain:

• More leaves

• More protein

• More digestible energy

• Less structural fibre

• Softer stems

• Greater palatability

As plants mature:

• Stems become thicker and woodier

• Seed heads or flowers develop

• Leaf-to-stem ratio falls

• Fibre increases

• Protein and digestibility decrease

This does not mean the youngest possible hay is always best. Highly digestible, early-cut hay may provide more calories than an easy keeper needs. Mid-maturity forage is often appropriate for ordinary adult horses, while younger forage may better suit growing horses, lactating mares and some performance horses. More mature hay may be useful for calorie-controlled horses, provided it is still clean, palatable and not so fibrous that intake falls. (University of Minnesota Extension)

Signs of More Mature Hay

Look for:

• Large or fully developed seed heads in grass hay

• Flowers in alfalfa or clover

• Thick, rigid stems

• Fewer leaves

• A coarse or straw-like feel

• Increased waste around feeders

One of the most useful corrections to the original article is this:

First cutting, second cutting or third cutting does not reliably tell you the nutritional value.

Maturity at the time of harvest matters more than the cutting number. A carefully harvested first cutting may be more digestible than an overmature second cutting, and vice versa. (University of Minnesota Extension)

Why Leaf-to-Stem Ratio Matters

Leaves contain more protein and digestible energy than stems.

A high leaf-to-stem ratio usually indicates:

• Earlier harvest

• Greater digestibility

• More protein

• Higher calorie content

• Better palatability

However, excessive leaf loss during handling can reduce quality. Very dry alfalfa may shatter during baling and feeding, leaving valuable leaves on the floor rather than inside the horse.

For an easy keeper, the most leafy hay is not necessarily the best choice. For a thin senior or lactating mare, leafier hay may be exactly what is needed.

How Should Good Hay Feel?

Take a handful and gently compress and bend it.

Good horse hay is generally:

• Soft enough to handle comfortably

• Flexible rather than brittle

• Free from sharp, rigid stems

• Pleasant for the lips and tongue

• Easy for the horse to chew

Very coarse hay is not automatically dangerous, but horses may eat less of it, waste more and struggle to maintain weight.

The texture matters particularly for:

• Senior horses

• Horses with worn or missing teeth

• Horses that quid or drop feed

• Horses with previous choke

• Foals and young horses

• Horses with painful oral disease

If the hay feels like a bundle of wire in your hand, it will not become magically softer when it reaches the horse’s mouth.

How Should Hay Smell?

Open the bale and smell the centre, not only the outside.

Suitable hay should smell:

• Fresh

• Grassy

• Neutral to mildly sweet

• Free from mustiness

• Free from fermentation or ammonia odours

Reject hay that smells:

• Musty

• Damp

• Sour

• Fermented

• Burnt

• Unusually smoky or caramelised

• Like chemicals or fuel

A caramel or tobacco-like smell can indicate heat damage during storage. A musty smell raises concern for mould even when the bale’s surface looks normal.

How Much Does Colour Matter?

Colour is useful, but it is one of the most overrated ways to judge hay.

Bright green hay may indicate:

• Limited sun bleaching

• Better preservation of carotene

• Appropriate curing

• Earlier harvest

However, colour does not tell you:

• Sugar content

• Calorie content

• Protein level

• Mineral balance

• Mould count

• Whether the hay contains weeds

• Whether it suits a metabolic horse

Sun-bleached or lightly rained-on hay may remain safe and nutritionally useful. Rain can reduce some nutrients and cause leaf loss, but clean rained-on hay is not automatically unsuitable for horses. Testing is the best way to decide whether the remaining nutrients meet the horse’s needs. (University of Minnesota Extension)

Remember:

Weeds can also be beautifully green.

Check the Inside of the Bale

Never judge a large hay purchase by looking at one attractive exterior bale.

Open several bales and check the centre for:

• White, grey, green or black mould

• Damp clumps

• Heat

• Discolouration

• Dust pockets

• Rotten areas

• Dead insects or animals

• Soil, stones, wire or rubbish

• Thick weeds

• Sharp seed heads

• Uneven curing

Mould and heating often begin inside the bale, where airflow is poorest.

University of Minnesota guidance specifically recommends inspecting the inside of at least one bale before purchasing hay. With a larger order, inspect several bales from different areas of the load. (University of Minnesota Extension)

How Much Dust Is Too Much?

Shake a flake gently outdoors in good light.

A small amount of fine plant material is common. A visible cloud hanging in the air is not desirable.

Dust may contain:

• Broken plant particles

• Soil

• Mould spores

• Fungal fragments

• Bacteria

• Endotoxins

• Mites and other allergens

Some of the most damaging respirable particles are too small to see. They can travel deep into the lungs and contribute to airway inflammation, coughing and reduced performance. Even hay that looks nutritionally excellent can have poor hygienic quality. (AAEP)

Horses at Particular Risk

Dust control is especially important for horses with:

• Equine asthma

• Recurrent coughing

• Nasal discharge

• Exercise intolerance

• Previous inflammatory airway disease

• Poorly ventilated housing

High-temperature steaming can reduce respirable particles and allergens. Thorough soaking, haylage or an appropriate pelleted or cubed forage may also reduce dust exposure. These methods should support the use of reasonably clean forage, not be used to rehabilitate rotten or heavily moulded hay. (AAEP)

Round bales can create an especially dusty breathing zone when horses push their heads into deep cavities in the bale. This is a poor arrangement for an asthmatic horse, even when it is remarkably convenient for the humans. (AAEP)

Never Feed Visibly Mouldy Hay

Mouldy hay should not be fed to horses.

Possible consequences include:

• Coughing

• Nasal discharge

• Airway inflammation

• Exacerbation of equine asthma

• Reduced appetite

• Colic

• Diarrhoea

• Exposure to mycotoxins

• Reduced athletic performance

Hay is more likely to mould when baled or stored at excessive moisture. Optimum moisture for ordinary horse hay is generally around 10% to 15%. Hay above approximately 16% moisture has a greater risk of moulding without appropriate preservation, while very wet hay may heat severely and create a fire hazard. (University of Minnesota Extension)

Soaking mouldy hay does not remove every fungal toxin.

Steaming can reduce respirable particles in appropriately selected hay, but heavily moulded or spoiled hay should still be discarded.

Hidden Hazards in Horse Hay

Some hay problems are more serious than poor protein or excess dust.

Sharp Awns and Foxtail-Type Grasses

Sharp seed awns from foxtail, barley, porcupine grass and related plants can become embedded in the gums, tongue and cheeks.

Affected horses may develop:

• Frothy drooling

• Mouth pain

• Reluctance to eat

• Difficulty swallowing

• Head tossing

• Resistance to oral examination

• Weight loss

Awn-related mouth injury can be extensive and may require sedation and careful removal by a veterinarian. (Merck Veterinary Manual)

Blister Beetles in Alfalfa

Blister beetles may be incorporated into alfalfa hay during harvest. The insects contain cantharidin, a potent irritant that remains toxic after the beetles die and does not disappear during ordinary hay storage.

Signs of cantharidin poisoning may include:

• Severe colic

• Mouth ulcers

• Depression

• Fever

• Diarrhoea

• Frequent or painful urination

• Repeated attempts to drink

• Sweating

• Rapid heart rate

• Weakness or shock

If elongated black, grey or striped beetles are found in alfalfa, stop feeding the entire suspect lot and contact your veterinarian. Infestation may be concentrated in only a few bales, so one clean-looking flake does not prove the whole load is safe. (University of Minnesota Extension)

Endophyte-Infected Tall Fescue

Tall fescue infected with a toxin-producing endophyte is particularly dangerous to pregnant mares.

Possible consequences include:

• Prolonged gestation

• Thickened placenta

• Difficult foaling

• Weak or stillborn foals

• Failure of udder development

• Poor milk production

Endophyte infection cannot be judged by looking at the plant. Pregnant mares should not receive infected fescue hay or pasture, particularly during late pregnancy. (Merck Veterinary Manual)

Toxic Weeds and Foreign Material

Inspect hay for:

• Poisonous plants

• Thick thistles

• Sharp awns

• Bracken fern

• Ragwort or regional toxic weeds

• Wire

• Plastic

• String

• Stones

• Animal carcass material

• Rodent or wildlife contamination

Weedy hay is not automatically poisonous, but plant identification matters. Some weeds reduce palatability, some cause physical injury and others remain toxic after drying.

Why Hay Analysis Is Worth Doing

Visual inspection tells you whether hay appears clean and palatable.

It cannot accurately tell you:

• Digestible energy

• Protein

• Sugar

• Starch

• Calcium

• Phosphorus

• Potassium

• Trace mineral content

• Whether the hay meets the needs of a specific horse

Hay of the same species can vary substantially between fields, cuttings, harvest dates and growing conditions.

A forage analysis is particularly valuable when feeding:

• Growing horses

• Pregnant or lactating mares

• Performance horses

• Hard keepers

• Overweight horses

• Horses with insulin dysregulation

• Horses with previous laminitis

• Horses with PSSM

• Horses with HYPP

• Horses with kidney or liver disease

• Hay as the major or only source of nutrition

How to Take a Representative Hay Sample

A laboratory result is only as useful as the sample submitted.

Do not pull one handful from the softest part of your favourite bale.

Use a properly sharpened hay core sampler and collect at least 12 cores from the same hay lot. A lot means hay harvested from the same field, cutting and time period under similar conditions.

For square bales, sample through the centre of the butt end. For round bales, insert the probe through the rounded side towards the centre. Mix all cores together and submit the combined sample in a clean, labelled bag. (Minnesota Crop News)

Test separate lots separately.

Combining samples from unrelated fields or cuttings produces an average that may accurately describe none of them.

How to Read a Hay Analysis

Always check whether the report is presented on an as-fed or dry-matter basis.

The dry-matter column removes the effect of water and is usually easier for comparing different feeds.

Result	What it tells you
Moisture	Storage stability and actual dry feed supplied
Digestible energy	How many calories the hay provides
Crude protein	Approximate total protein content
ADF	Higher values generally mean lower digestibility
NDF	Higher values generally reduce voluntary intake
WSC and ESC	Water-soluble and simple sugars
Starch	Rapidly digested carbohydrate
NSC	Combined measure of starch and selected sugars
Calcium and phosphorus	Major mineral balance
Potassium	Particularly relevant in HYPP
Trace minerals	Helps select an appropriate balancer

Moisture

A broad target for dry horse hay is around 10% to 15% moisture.

• Under 10% may be brittle and prone to leaf shatter.

• Above 16% increases mould risk without preservation.

• Above 25% creates major heating and potential fire concerns. (University of Minnesota Extension)

Crude Protein

Typical ranges vary widely:

• Grass hay may range from approximately 8% to 14%.

• Mixed legume-grass hay may be around 14% to 17%.

• Legume hay may reach 15% to above 20%.

Most adult maintenance horses do not require extremely high-protein hay, but growing horses and lactating mares have greater requirements. Protein percentage must be interpreted alongside total intake, protein quality and the rest of the ration. (University of Minnesota Extension)

Acid Detergent Fibre

ADF reflects less digestible fibre fractions.

Lower ADF generally means greater digestibility. Values below approximately 45% are commonly considered acceptable for horses, although the ideal value depends on whether the horse needs weight gain or calorie restriction. (University of Minnesota Extension)

Neutral Detergent Fibre

NDF relates to total cell-wall material and expected voluntary intake.

As NDF increases, horses may eat less and take longer to consume the hay. Values below approximately 65% are generally considered more acceptable, although moderately higher-fibre hay can be useful for selected easy keepers if they remain willing and able to consume enough. (University of Minnesota Extension)

Nonstructural Carbohydrates

NSC broadly represents starch and selected sugars.

Horses with equine metabolic syndrome generally require hay at or below approximately 10% NSC on analysis, together with controlled total intake. Visual appearance cannot identify low-sugar hay reliably. (Merck Veterinary Manual)

Soaking can reduce water-soluble carbohydrates, but the reduction varies with hay type, water temperature and soaking time. Soaking should not be used as a substitute for testing when the horse has a serious laminitis risk. (University of Minnesota Extension)

Relative Feed Value

Relative feed value is calculated mainly from ADF and NDF and was developed for cattle.

It may help compare similar hay lots, but it is not sufficiently complete to balance a horse’s diet. It does not describe protein quality, sugar, minerals, cleanliness or suitability for the individual horse. (equine.mgcafe.uky.edu)

Which Hay Is Best for Different Horses?

There is no single best hay for every horse.

Horse	Useful hay characteristics
Adult maintenance horse	Clean mid-maturity grass or mixed hay with moderate energy
Easy keeper or overweight horse	More mature, lower-energy hay that remains palatable and nutritionally adequate
Horse with EMS or laminitis risk	Laboratory-tested hay at or below approximately 10% NSC
Hard keeper	Earlier-cut, more digestible grass hay or a grass-alfalfa mixture
Performance horse	Digestible, higher-energy hay matched to workload
Growing horse	Quality protein, lysine and balanced minerals, often from a legume-grass mixture
Pregnant or lactating mare	Higher-quality forage with adequate protein, calcium and energy, plus correct mineral balance
Senior with poor teeth	Soft, leafy hay or soaked forage pellets, cubes or complete feed
Horse with equine asthma	Very low-dust forage, steamed hay or an appropriate forage alternative
HYPP horse	Hay tested for potassium, usually avoiding high-potassium forage
Pregnant mare in fescue regions	Confirmed endophyte-free hay

The best choice is the forage that allows the horse to maintain appropriate body condition and health without requiring excessive concentrate supplementation.

Grass Hay, Alfalfa or Mixed Hay?

Grass Hay

Common grass hays include:

• Timothy

• Orchardgrass

• Brome

• Bermuda

• Teff

• Oat hay

• Meadow mixtures

Grass hays are generally lower in energy, protein and calcium than legume hay, although there is considerable overlap.

They often suit:

• Adult maintenance horses

• Easy keepers

• Horses needing more chewing time per calorie

• Horses requiring a forage-first diet without excessive energy

Late-harvested grass hay may be too coarse and low in protein for young, lactating or underweight horses.

Alfalfa or Lucerne

Alfalfa is generally:

• Higher in digestible energy

• Higher in protein

• Higher in calcium

• More digestible

• Often lower in NSC than cool-season grass hay

It can suit:

• Growing horses

• Lactating mares

• Hard keepers

• Some performance horses

• Horses needing additional quality protein

• Ulcer-conscious feeding plans

It can provide excessive calories for easy keepers and requires additional caution in HYPP, kidney disease, urinary-stone history and areas where blister beetles occur. (University of Minnesota Extension)

Mixed Grass and Alfalfa Hay

A grass-alfalfa mixture is often an excellent compromise.

It may provide:

• More protein than grass alone

• More fibre than pure alfalfa

• Moderate calories

• Better calcium balance with grain

• Greater palatability

• Flexibility across several classes of horses

The actual proportion of grass and alfalfa still needs to be known or estimated, particularly when feeding metabolic or growing horses.

Is the Greenest, Softest Hay Always the Best?

No.

The highest-energy, most digestible hay is useful when the horse needs those nutrients.

It may be inappropriate when the horse:

• Is already overweight

• Has insulin dysregulation

• Is sedentary

• Has a history of laminitis

• Gains weight very easily

• Receives additional high-calorie feed

A mature adult horse may remain healthier on clean, moderate-energy grass hay than on premium dairy-quality alfalfa.

The phrase “horse-quality hay” should therefore mean safe and suitable, not simply leafy and expensive.

How Much Hay Should a Horse Eat?

An average healthy horse commonly consumes around 2% to 2.5% of body weight in total dry matter each day, with at least half coming from forage. Many ordinary adult horses can receive nearly their entire ration as forage. (Merck Veterinary Manual)

A useful forage starting range is approximately 1.5% to 2% of body weight daily.

For a 500-kilogram horse:

• 1.5% equals 7.5 kilograms of forage dry matter.

• 2% equals 10 kilograms of forage dry matter.

Because ordinary hay contains some water, the actual weight placed in the feeder will be slightly greater.

The final amount depends on:

• Body condition

• Workload

• Pasture intake

• Hay energy

• Pregnancy or lactation

• Age

• Dental health

• Metabolic disease

• Weather

Weigh Hay, Do Not Count Flakes

One flake may weigh less than one kilogram. Another can weigh three kilograms or more.

Weigh several flakes from each new batch and calculate the average. Repeat the process when the bale size, supplier or cutting changes.

“Two flakes” is a stable instruction.

It is not a reliable ration.

How Should You Introduce New Hay?

A new hay batch should be introduced gradually, even when the supplier describes it as the same species and cutting.

Replace approximately 20% to 25% of the old hay every other day. This generally produces a complete transition over at least one week, with 10 to 14 days being sensible for sensitive horses. (University of Minnesota Extension)

A practical schedule is:

Transition period	Old hay	New hay
Days 1 to 3	75%	25%
Days 4 to 6	50%	50%
Days 7 to 9	25%	75%
Days 10 to 14	0%	100%

Use a slower transition for horses with:

• Previous colic

• Laminitis

• Insulin dysregulation

• Recurrent diarrhoea

• Poor dentition

• Recent transport

• Significant weight loss

• A major change from grass to alfalfa or vice versa

Pause the transition if appetite falls, manure changes or abdominal discomfort develops.

How Worried Should You Be About the Hay?

Lower Concern

The hay is:

• Clean

• Dry

• Pleasant-smelling

• Free from visible mould

• Slightly bleached but otherwise normal

• A suitable nutritional match for the horse

The horse is eating normally and maintaining appropriate condition.

What to do: continue feeding and monitor the horse. Use analysis if nutritional precision is needed.

Moderate Concern

The hay is:

• Coarser than the previous batch

• Very mature or stemmy

• Being wasted

• Slightly dusty

• Associated with softer manure

• Causing the horse to eat more slowly

What to do: stop increasing the new hay, inspect several bales and consider forage analysis. Arrange a dental examination if chewing has changed.

High Concern

The hay has:

• A musty smell

• Visible dust clouds

• Damp clumps

• Unusual heat

• White, green, grey or black growth

• Sharp awns

• Toxic or unidentified weeds

• Blister beetles

• Wildlife contamination

• Foreign material

Or the horse develops coughing, reduced appetite, mouth pain or recurrent colic.

What to do: stop feeding the suspect lot and contact your veterinarian or nutritionist. Keep representative samples and supplier information.

Critical

The horse develops:

• Severe colic

• Breathing difficulty

• Profuse diarrhoea

• Feed refusal with rapid deterioration

• Frequent painful urination after eating alfalfa

• Muscle tremors

• Weakness or collapse

• Heavy drooling and inability to eat

• Neurological abnormalities

• Acute laminitis signs

What to do: seek emergency veterinary care immediately.

When Is Suspect Hay an Emergency?

Call your veterinarian urgently if your horse develops:

• Laboured breathing

• Repeated coughing with respiratory distress

• Severe or persistent abdominal pain

• Repeated rolling

• Profuse watery diarrhoea

• Feed or saliva from the nostrils

• Inability to swallow

• Mouth bleeding or severe drooling

• Frequent painful urination

• Muscle trembling or synchronous diaphragmatic flutter

• Hot, painful feet

• Bounding digital pulses

• Blindness, circling or incoordination

• Weakness or collapse

Remove the suspect hay from every horse with access to the same lot.

Do not throw away all evidence. Keep:

• A representative feed sample

• The bale string or wrapping

• Supplier details

• Harvest information

• Batch or lot numbers

• Photographs of contamination

• A list of affected horses and signs

This information may be important for toxicology testing or tracing the source.

What Else Can Look Like a Hay Problem?

A horse becoming unwell after a hay change does not prove that hay is the only cause.

Coughing May Also Be Caused By

• Equine asthma

• Influenza

• EHV

• Pneumonia

• Poor stable ventilation

• Arena dust

• Other environmental allergens

Weight Loss May Also Be Caused By

• Dental disease

• Parasites

• PPID

• Gastric disease

• Chronic pain

• Liver or kidney disease

• Malabsorption

• Social competition

• Insufficient total intake

Colic May Also Be Caused By

• Intestinal displacement

• Strangulation

• Sand

• Enteroliths

• Parasites

• Inflammation

• Lipomas

• Urinary or reproductive disease

Mouth Pain May Also Be Caused By

• Sharp dental points

• Fractured teeth

• Oral foreign bodies

• Chemical irritation

• Vesicular stomatitis

• Other infections

Timing matters, but it does not replace a diagnosis.

What Should You Do Before Buying Hay?

1. Define the Horse’s Needs

Record:

• Body weight

• Body-condition score

• Workload

• Age

• Pregnancy or lactation

• Metabolic status

• Dental health

• Previous respiratory disease

• Current concentrate and supplements

2. Ask About the Hay

Ask the supplier:

• What species are present?

• Is it grass, legume or mixed?

• Where was it grown?

• When was it harvested?

• What stage of maturity was it?

• Was it rained on?

• Was a preservative used?

• How was it stored?

• Is a forage analysis available?

• Is it all from one lot?

• Has the supplier had mould or toxic-plant concerns?

• For alfalfa, is blister beetle risk relevant?

• For fescue, is it endophyte-free?

3. Open Several Bales

Do not inspect only the neatest bale selected by the seller.

Check the centre of bales from different parts of the load.

4. Smell and Shake the Hay

Reject obvious mould, mustiness, dampness or heavy dust.

5. Identify the Plants

Know what you are purchasing.

Ask for help from an agronomist, extension officer or equine nutritionist if species or weeds are unclear.

6. Obtain a Representative Sample

Use a hay probe and submit the lot for equine forage analysis.

7. Buy Enough for a Gradual Transition

Do not wait until the old hay is completely gone before introducing the new one.

8. Trial a Small Quantity

Where possible, purchase a few bales before committing to an entire season’s supply.

Confirm that the horse:

• Eats it willingly

• Maintains normal manure

• Does not cough excessively

• Does not develop mouth pain

• Maintains appropriate condition

Common Hay-Selection Mistakes

Buying Only by Colour

Green hay can be too rich, mouldy or full of weeds.

Assuming Later Cutting Means Better Hay

Cutting number does not replace information about maturity and analysis.

Feeding the Same Hay to Every Horse

A lactating mare, an obese pony and a senior with poor teeth have different needs.

Failing to Open the Bale

Mould and heat often hide in the centre.

Feeding Mouldy Hay After Soaking It

Water does not reliably remove mycotoxins or make spoiled forage safe.

Using Flake Number Instead of Weight

Flake weight changes between bales and suppliers.

Not Testing Hay for a Metabolic Horse

Colour, species and smell cannot identify hay below 10% NSC.

Ignoring Storage

Excellent hay can become poor hay under a leaking roof or on wet ground.

Changing Hay Overnight

The hindgut microbiome needs time to adapt, even when the new hay appears superior.

How Should Hay Be Stored?

Store hay:

• Under a watertight roof

• In a dry, ventilated building

• Off the ground on pallets

• Away from leaking walls

• Protected from rodents and wildlife

• Organised by cutting and lot

• With older hay used first

• Where heating or smoke can be detected promptly

Do not stack hay directly on soil or concrete that allows moisture to move into the bottom bales.

Hay stored on wet surfaces can experience major spoilage. Round bales stored outdoors should be elevated, well covered and placed on a well-drained site. (University of Minnesota Extension)

Wet, steamed or soaked hay should be fed promptly. In warm or humid conditions, discard leftovers rather than allowing them to sit and ferment. (Merck Veterinary Manual)

Can Hay Quality Problems Be Prevented?

Not every poor harvest can be prevented, but owners can reduce risk by:

• Buying from established equine forage suppliers

• Requesting harvest and storage information

• Inspecting multiple bales

• Testing each hay lot

• Keeping hay dry

• Rotating stock

• Using feeders that reduce soil contamination

• Avoiding deep, dusty round-bale feeding zones

• Monitoring body condition monthly

• Weighing hay rather than counting flakes

• Introducing new lots gradually

• Acting early when appetite, manure or coughing changes

The best feeding programme is not based on finding one perfect bale forever.

It is based on repeatedly checking that the forage still suits the horse.

Will My Horse Do Well on This Hay?

The hay is probably appropriate when the horse:

• Eats it willingly

• Maintains ideal body condition

• Produces normal manure

• Has no new cough

• Chews comfortably

• Wastes little

• Maintains normal energy and performance

• Has appropriate blood and metabolic results where monitored

The hay may need changing or balancing when the horse:

• Gains or loses unwanted weight

• Leaves large quantities uneaten

• Develops a cough

• Quids or drops forage

• Produces persistently loose or dry manure

• Becomes footsore

• Requires a large amount of concentrate to maintain condition

• Develops a mineral or vitamin deficiency

• Shows recurrent colic after a batch change

The horse is the final quality-control test.

The laboratory tells you what is in the hay. The horse tells you whether the entire plan is working.

FAQs About Choosing Hay for Horses

Is bright green hay always the best?

No. Green colour can indicate good curing and preserved carotene, but it does not reveal sugar, calories, mould, weeds or mineral content. Slightly bleached clean hay may still be perfectly suitable.

Is first-cut or second-cut hay better?

Neither is automatically better. Plant maturity at harvest is more important than cutting number. Analyse the specific batch rather than choosing by label.

Can horses eat rained-on hay?

Yes, provided it was dried correctly, remains free from mould and is nutritionally suitable. Rain may reduce dry matter, soluble carbohydrates and leaf content, so testing is useful. (University of Minnesota Extension)

Can I feed slightly mouldy hay if I soak or steam it?

Visibly mouldy or spoiled hay should not be fed. High-temperature steaming can reduce respirable particles in otherwise suitable hay but is not permission to feed rotten forage.

What hay is best for a horse with insulin dysregulation?

Use forage analysis to select hay at or below approximately 10% NSC. Feed a measured amount through a slow feeder or divided meals according to the veterinary weight and metabolic plan. (Merck Veterinary Manual)

Final Thoughts

Choosing hay is not a beauty contest.

The best hay is not automatically:

• The greenest

• The leafiest

• The most expensive

• The highest in protein

• The second cutting

• Pure alfalfa

• Timothy

• Whatever the previous horse ate

Good hay must pass three tests:

1. Is it hygienically safe?
   It should be free from visible mould, excessive dust, toxic weeds, dangerous insects and foreign material.

2. Is it nutritionally appropriate?
   Its energy, protein, fibre, sugar and minerals should match the horse.

3. Will the horse eat and tolerate it?
   It must be palatable, chewable and compatible with normal weight, manure, respiratory health and performance.

Inspect the hay. Open the bale. Weigh it. Test the lot. Introduce it gradually. Monitor the horse.

That is far more reliable than deciding the bale looks green enough and hoping the digestive tract agrees.

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If you are unsure whether a hay batch suits your horse’s weight, workload, metabolic health or dental function, ASK A VET™ can help you organise the forage analysis and feeding history before you finalise the ration with your veterinarian or equine nutritionist.