Feeding Horses in Winter: Cold Weather Diet Tips

Feeding Horses in Winter: Adjusting for Cold and Reduced Forage Quality

Winter brings a unique set of challenges for horse owners, and nutrition is right at the top of the list. Shorter days, plummeting temperatures, frozen water troughs, and pastures that have long since stopped growing — it all adds up to a season where your horse's dietary needs change significantly.

Getting winter feeding right isn't just about tossing an extra flake of hay into the stable. It requires an understanding of how cold weather affects your horse's energy requirements, how forage quality shifts through the winter months, and what practical steps you can take to keep your horse in good condition until spring arrives.

Let's break it all down.

Why Winter Changes Your Horse's Nutritional Needs

Horses are remarkably well-adapted to cold weather. Their thick winter coats, ability to redirect blood flow, and natural behavioural responses all help them cope. But maintaining body temperature in cold conditions costs energy — and that energy has to come from somewhere.

The Thermoneutral Zone

Every horse has a thermoneutral zone — a temperature range where they don't need to expend extra energy to stay warm. For most adult horses with a full winter coat, this zone sits roughly between 0°C and 25°C (32°F to 77°F). When temperatures drop below this range, your horse's body starts burning more calories just to maintain core body temperature.

The lower critical temperature (LCT) depends on several factors:

• Coat condition — A dry, fluffy winter coat provides excellent insulation. A wet or clipped coat shifts the LCT upward dramatically.
• Body condition — Horses carrying adequate fat reserves have better insulation and energy stores to draw on.
• Wind and rain — Wind chill and moisture are far more impactful than air temperature alone. A wet, windy 5°C day can be harder on your horse than a dry, still day at -10°C.
• Age and health — Older horses and those with health conditions may struggle to thermoregulate effectively.

As a general rule, for every 1°C drop below the LCT, a horse's energy requirements increase by approximately 1%. That might not sound like much, but during a prolonged cold snap, it adds up quickly.

The Real Problem: Reduced Forage Quality

While cold weather increases energy demand, winter simultaneously delivers a second blow — the quality of available forage declines.

What Happens to Pasture in Winter?

Once grass stops actively growing, its nutritional value drops considerably. Winter pasture is often:

• Lower in digestible energy — Mature, dormant grass has more fibre and less readily available energy than lush spring or summer pasture.
• Lower in protein — Crude protein levels in dormant pasture can fall to 6-8%, compared to 12-16% or more in actively growing grass.
• Lower in vitamins — Key vitamins like vitamin A (from beta-carotene) and vitamin E decline substantially in dead or dormant forage.
• Variable in mineral content — Mineral levels depend on the soil, but bio-availability can shift in mature forage.

In practical terms, most horses can no longer meet their nutritional needs from pasture alone once winter sets in. Even horses on large acreages of grassland will typically need supplemental hay or other forage sources.

Hay Quality Varies Too

Don't assume that just because you're feeding hay, you've solved the problem. Hay quality varies enormously depending on when it was cut, how it was stored, and what species of grass or legume it contains.

Late-cut hay tends to be more fibrous and less digestible. Hay that has been rained on before baling may have lost soluble nutrients. Poorly stored hay can develop mould, which is a health hazard in its own right.

If you haven't already, consider getting your hay analysed. Knowing the actual energy, protein, and mineral content of your hay removes the guesswork and allows you to supplement accurately.

How to Adjust Your Horse's Winter Diet

Now that we understand the twin challenges — higher energy demand and lower forage quality — let's look at practical strategies.

1. Increase Forage First

Forage should always be the foundation of your horse's diet, and in winter, it becomes even more important. Here's why: the microbial fermentation of fibre in the hindgut produces significant amounts of heat as a byproduct. This is sometimes called the "internal furnace" effect.

Feeding more hay is genuinely one of the best ways to help your horse stay warm. Aim for a minimum of 2% of body weight in forage per day during cold weather — that's 10 kg of hay per day for a 500 kg horse. During extreme cold, you may need to increase this further.

Practical tips:

• Feed hay in multiple smaller meals throughout the day and evening rather than one or two large feeds.
• Provide hay late in the evening so your horse has forage to work through during the coldest overnight hours.
• Use slow-feeder hay nets to extend eating time and reduce waste.
• If pasture is very limited, consider offering ad-lib hay to allow your horse to self-regulate intake.

2. Assess and Supplement for Forage Deficiencies

If your hay is of average or below-average quality, your horse may need additional support. Common deficiencies in winter diets include:

• Vitamin A — Fresh, green forage is the primary dietary source. Hay loses vitamin A over time, especially after several months of storage. Supplementation is often warranted.
• Vitamin E — Another nutrient that's abundant in fresh pasture but declines rapidly in conserved forage. Horses without access to green pasture for extended periods are at risk of deficiency.
• Protein — If your hay tests low in crude protein (below 8-10%), you may need to add a protein source, particularly for young, growing horses, broodmares, or horses in work.
• Key minerals — Zinc, copper, and selenium are frequently deficient in UK and European hay and pasture. A well-formulated mineral supplement or balancer can fill these gaps.

The best way to know exactly what your horse needs is to analyse your horse's diet based on what you're actually feeding. This takes the guesswork out of supplementation and helps you avoid both under- and over-supplying nutrients.

3. Consider Adding Concentrates or High-Energy Feeds

For some horses, extra hay alone won't be enough to maintain body condition through winter — particularly hard-working horses, poor doers, very young horses, or older horses with dental issues that limit their ability to chew long-stem forage.

In these cases, you can add energy through:

• Fibre-based feeds — Beet pulp (sugar beet), hay cubes, chaff, and soy hulls are excellent sources of digestible fibre that complement the forage portion of the diet.
• Cereal grains — Oats, barley, and other grains provide concentrated energy but should be introduced gradually and fed in moderation to avoid digestive upset.
• Oils and fats — Adding vegetable oil (such as linseed or soya oil) to feeds is an efficient way to boost calorie intake without increasing meal volume. Oil provides roughly 2.5 times more energy per gram than carbohydrates.
• Commercial feeds — A quality conditioning feed or balancer pellet, chosen to match your horse's workload and forage base, can be a convenient way to top up energy and nutrients.

4. Monitor Body Condition Regularly

Thick winter coats are deceptive. A horse can lose significant body condition under a fluffy coat without you noticing — until spring arrives and you're confronted with a ribby horse.

Make a habit of hands-on body condition scoring every two to three weeks throughout winter. Run your hands over the ribs, along the topline, behind the shoulder, and over the croup. You should be able to feel the ribs with light pressure but not see them. If you're starting to struggle to feel the ribs, your horse may be gaining too much weight. If the ribs are easily visible or prominent to the touch, action is needed immediately.

Don't wait until your horse has lost significant condition to act. It's much harder (and more expensive) to put weight back on in the depths of winter than it is to maintain it.

5. Water: The Overlooked Winter Essential

Dehydration is a surprisingly common issue in winter. Horses tend to drink less when water is ice-cold, and reduced water intake directly affects gut motility. Impaction colic — one of the most common winter colics — is closely linked to inadequate water consumption combined with high dry-matter forage diets.

To encourage adequate water intake:

• Break ice and check water sources at least twice daily. Automatic waterers can freeze, and horses won't break thick ice themselves.
• Offer lukewarm water when possible. Studies have shown horses drink significantly more water when it's offered at 7-18°C compared to near-freezing temperatures.
• Add a loose salt supplement to feed. This stimulates thirst and helps ensure your horse is drinking enough. A tablespoon of plain table salt (sodium chloride) daily works well for most horses.
• Consider soaking hay or feeding wet feeds. Soaked beet pulp, dampened chaff, or hay soaked for 10-15 minutes all add moisture to the diet.

Special Considerations for Different Horses

Senior Horses

Older horses often face dental problems that make chewing long-stem hay difficult or impossible. Soaked hay cubes, beet pulp mashes, and senior-specific feeds can be lifesavers for aged horses in winter. They may also need additional protein to maintain muscle mass and benefit from joint supplements to manage the increased stiffness cold weather brings.

Horses in Work

Horses that continue to work through winter have compounded energy needs — they need fuel both for performance and for thermoregulation. Clipped horses lose their natural insulation and will need proportionally more calories than unclipped horses, as well as appropriate rugging.

Easy Keepers and Native Breeds

Not every horse needs a big increase in feed during winter. Hardy native breeds and good doers may maintain condition perfectly well on adequate hay alone. Over-feeding these horses can lead to obesity and increase the risk of laminitis in spring. Monitor condition carefully and resist the urge to over-rug and over-feed.

Horses Living Out 24/7

Horses that live out without stabling need reliable access to shelter from wind and rain, ad-lib forage, and unfrozen water. Their energy requirements will generally be higher than stabled horses, particularly in wet and windy conditions. Shelter — even a simple field shelter or thick hedgerow — significantly reduces the energy cost of thermoregulation.

A Simple Winter Feeding Checklist

• ✅ Provide at least 2% body weight in forage daily (more in extreme cold)
• ✅ Feed hay in the evening to fuel overnight warmth
• ✅ Get your hay tested to know its nutritional value
• ✅ Supplement vitamins A and E if there's no access to fresh pasture
• ✅ Use a mineral supplement or balancer to fill common gaps
• ✅ Add concentrates or oil for horses that need extra energy
• ✅ Body condition score your horse every 2-3 weeks with your hands
• ✅ Ensure access to unfrozen water at all times
• ✅ Add salt to encourage drinking
• ✅ Adjust feeding for individual needs — age, workload, breed, housing

Final Thoughts

Winter feeding doesn't have to be complicated, but it does require attention and a willingness to adjust as conditions change. The core principle is simple: increase quality forage, fill the nutritional gaps that conserved forage can't cover, ensure adequate water intake, and monitor your horse's body condition throughout the season.

By taking a proactive approach now, you'll bring your horse through winter in good health and condition, ready to thrive when the days start lengthening again. And if you're unsure whether your current feeding plan stacks up, take the time to properly analyse what you're feeding — it's the single most valuable step you can take toward getting winter nutrition right.