Best Horse Feed for Weight Gain: What Actually Works and What to Avoid

The instinct when a horse drops weight is to add grain. It feels like the direct solution, and it is usually the wrong first move.

Pouring starch into a thin horse can trigger colic, ulcers, and unwanted behavioural energy — while doing less for body condition than a change in forage would have done.

There is also a timing problem specific to Alberta. A horse that gained well through summer can lose it all in six weeks of hard cold, because a -30°C stretch raises energy needs by roughly 40 percent.

This guide covers what the best horse feed for weight gain actually looks like, in what order to make changes, how to know whether it is working, and the health issues to rule out before you change anything.

What Is the Best Horse Feed for Weight Gain?

The best approach for weight gain is more and better forage first, then calories from fat and digestible fibre — not from added starch. Grain-heavy feeding adds risk faster than it adds condition.

That order matters. University of Minnesota Extension recommends starting with as much forage as possible, then moving to higher-quality hay such as alfalfa or an immature grass hay before reaching for concentrates.

When a concentrate is needed, UMN suggests switching to a performance feed in the 10 to 12 percent fat range rather than simply feeding more of a lower-fat product.

The reason fat works is density. Fat carries far more energy per pound than grain, which means you can add meaningful calories without loading the hindgut with starch.

But none of this matters if you skip the first question.

Why Should You Find Out Why a Horse Is Thin First?

Because a healthy horse is rarely too thin, and feeding around an unaddressed problem wastes months. Veterinary guidance is consistent on this: identify the cause before changing the ration.

Common reasons a horse loses condition:

•      Dental problems. Worn, sharp, or missing molars mean hay goes in and comes out barely chewed. Very common in seniors.

•      Parasites. Run a fecal egg count rather than guessing.

•      Gastric ulcers. Often show up as poor appetite, picky eating, or resistance under saddle.

•      PPID (Cushing's) or other endocrine disease. Especially relevant in older horses with a long coat that sheds late.

•      Pain. Arthritis, hoof pain, or back pain reduce intake and movement.

•      Herd position. A bottom-of-the-pecking-order horse gets pushed off the round bale all winter and nobody notices.

•      Simple under-feeding. Feeding by flakes and scoops instead of pounds hides large errors.

 

That last one catches more people than it should. Bale weights vary widely and a scoop is not a unit of measurement — weigh both hay and concentrate before concluding the ration is adequate.

If the cause is management rather than the ration, the fix may not be feed at all. Blanketing, feeding separately from herd mates, dental work, and parasite control can all restore condition without a single change to the feed bag.

Work with your veterinarian on the diagnostic side. A ration change layered on top of an untreated dental or ulcer problem rarely produces the result you want.

How Do You Know How Much Weight a Horse Needs to Gain?

Use a body condition score alongside a weight tape, and record both. Visual impression alone is unreliable, especially under a thick Alberta winter coat.

Most horses should sit at a body condition score of 5 to 6 on the nine-point scale, with broodmares typically 5 to 7. At a score of 5, you should not see ribs from the side but should be able to feel them easily by hand.

The calorie requirement behind a single score point is larger than most owners expect.

What you are asking for	What it actually takes
One body condition score point	Roughly 40–50 lb of body weight for an 1,100 lb horse
One pound of gain	Approximately 8,000–9,000 kcal above maintenance
A full score point (≈45 lb)	Roughly 380,000 kcal above maintenance in total
Realistic timeframe	Not less than 60 days — often longer

 

Figures per Purina Animal Nutrition and Platinum Performance. Individual metabolism varies considerably.

Spread across sixty days, that works out to a daily surplus in the range of 6,000 kcal — a real change to the ration, not a handful of extra grain.

The practical monitoring kit is simple: a weight tape, a body condition scorecard, profile photos from both sides, and a kitchen scale for weighing feed. Take new photos every time you tape the horse, because progress is hard to see day to day.

Why Should Forage Come Before Any Feed?

Because forage is where the volume is, and volume is where most weight gain actually comes from. It is also the safest calorie source a horse has.

Target at least 1.5 percent of body weight in forage daily, and preferably 2 percent. For underweight horses, total dry matter intake in the range of 2 to 2.5 percent of body weight is a common working target.

For a 1,100 lb horse that means roughly 16 lb as an absolute floor, about 22 lb as a sensible target, and up to 28 lb at the upper end.

Before adding anything else, work through the forage options.

Forage change	What it does	Best for
More of the same hay	Increases total calories with no diet change	Horses not currently getting free-choice forage
Better-quality hay	Earlier-cut hay is more digestible and higher in energy	Horses already eating plenty of stemmy, mature hay
Add alfalfa	Higher in energy and protein, often lower in sugar than grass hay	Horses needing protein for muscle as well as condition
Hay cubes or pellets	Same nutrition, far easier to chew	Seniors and horses with dental limitations
Beet pulp	Highly digestible fibre, soaks readily	Adding calories without starch

 

Alfalfa deserves specific mention because it does double duty. It supplies more energy and protein than most grass hay while typically testing lower in sugar, which makes it useful for horses that need condition but cannot tolerate a starch load.

Our guide to alfalfa hay for horses covers how much is appropriate and where the limits are, and how alfalfa compares with timothy explains the trade-offs if you are blending.

One caution: increasing hay only helps if the horse can actually chew and digest it. That is where seniors often stall.

What Kind of Feed Adds Weight Safely?

Once forage is maximized and the horse still needs more, fat and digestible fibre are the safe levers. Starch is the one to limit.

Calorie source	Advantages	Watch for
Added fat (oil, rice bran, fat supplements)	Very energy dense, low starch, no excitability	Introduce slowly; requires vitamin E support
Beet pulp	Digestible fibre, well accepted, soaks easily	Bulky; soak before feeding
Performance feed (10–12% fat)	Balanced vitamins and minerals included	Follow label rates; introduce gradually
Alfalfa cubes or pellets	Forage calories plus protein	Soak for horses with poor teeth
Plain grain / straight oats	Cheap and familiar	Highest colic, ulcer, and behaviour risk

 

Commercial fat supplements are typically fed at around 1 to 2 lb per day depending on the product. Because high-fat diets increase oxidative demand, Kentucky Equine Research recommends supplementing a bioavailable natural-source vitamin E alongside them.

Introduce any oil or fat slowly. The hindgut needs time to adapt, and a sudden jump causes loose manure and refusals.

How much concentrate is too much in one meal?

Never feed more than about 0.5 percent of body weight in concentrate in a single meal — roughly 5 lb for a 1,000-pound horse.

If a horse needs more than that to gain, split it into several smaller meals across the day rather than increasing meal size. Large starch meals overwhelm small intestinal digestion and push undigested starch into the hindgut, which is how colic and acidosis start.

This is one reason fat is preferred for hard keepers. It lets you add calories without increasing meal volume.

You can browse horse feed options to see what formats are available, including Masterfeeds equine products and Hi-Pro feeds. Check the guaranteed analysis on any product against your horse's actual requirement rather than choosing by label claims.

What Is the Best Senior Horse Feed for Weight Gain?

For seniors, the limiting factor is usually chewing ability rather than calorie content — so the best feed is whichever one the horse can physically process.

A senior with functional molars often does perfectly well on good hay plus added fat. A senior with badly worn or missing teeth cannot extract nutrition from long-stem hay no matter how much you put in front of it.

For those horses, the answer is forage replacement rather than forage supplementation:

•      Soaked hay cubes or pellets deliver forage nutrition in a chewable form

•      Complete senior feeds are formulated with enough fibre to replace hay partially or entirely

•      Beet pulp adds soaked, digestible fibre calories

•      Chopped forage works for horses that can still chew but tire quickly

 

Soaking matters for more than chewing. Dry pellets and cubes carry a choke risk in horses that bolt their feed or have poor dental function.

Watch for quidding — balls of partially chewed hay dropped on the ground. It is the clearest sign that dental function, not diet, is the problem, and it means a dental exam before a feed change.

Our senior horse feed comparison goes through the specific product categories, and timothy-alfalfa cubes are one soaked-forage option worth knowing about.

Do Weight Gain Supplements Actually Work?

Fat-based supplements do add calories, and that part works. What they cannot do is fix a problem that is not caused by a calorie shortage.

A supplement is useful when a horse is already eating adequate forage, has no untreated health issue, and simply needs more energy density than the current ration provides.

It is not useful when the horse has dental disease, ulcers, parasites, PPID, or is being bullied off the feed. In those cases the supplement is an expense that delays the real fix.

Be cautious about products making broad promises. There is no supplement that adds condition independently of calories, and the marketing that suggests otherwise is worth ignoring.

If you are choosing between a fat supplement and simply upgrading the hay, the hay is usually the better value. It addresses volume, chew time, and hindgut health at the same time.

Why Do Alberta Horses Lose Weight Every Winter?

Because cold weather raises energy requirements dramatically, and the increase is much larger than most owners account for.

A horse's lower critical temperature is the point below which it must burn extra energy to stay warm. For an acclimated adult horse with a full winter coat, that threshold sits around -8°C, though it rises sharply if the horse is wet, clipped, thin, or unprotected from wind.

Below that point, digestible energy requirements increase by roughly one percent for every degree Fahrenheit of additional cold.

Temperature	Approx. increase in energy need	Extra hay equivalent
-10°C	~4%	~1 lb/day
-20°C	~22%	~4 lb/day
-25°C	~31%	~6 lb/day
-30°C	~40%	~8 lb/day
-35°C	~49%	~10 lb/day

 

Calculated from extension guidance using a lower critical temperature of -8°C for an acclimated horse in good condition with a dry winter coat. Wind chill, wet coats, thin body condition, and clipping all raise the threshold and increase the requirement further.

Two things follow from that table, and both are practical.

Forage is the right lever, not grain. Hindgut fermentation of fibre generates substantial body heat, which grain digestion does not. More hay is literally warmer than more grain.

Build condition in the fall, not in January. Extension guidance notes that horses may struggle to gain condition during extreme cold, because the surplus calories go to heat production instead of body reserves.

That is the single most useful piece of timing advice for an Alberta owner. If a horse is thin in October, act then — trying to put weight on during a February cold snap is working against the weather.

Plan your winter hay volume with those numbers in mind. Our guide to calculating daily hay requirements shows how to convert this into actual bales.

How Fast Should a Horse Gain Weight?

Slowly. Expect a minimum of 60 days for a single body condition score point, and treat anything faster as a reason to check rather than celebrate.

Rushing creates its own problems. Rapid calorie increases cause digestive upset, and in severely underweight horses they carry genuine risk.

Horses at a body condition score of about 2 or lower need veterinary supervision for refeeding. A sudden calorie load in a severely malnourished horse can cause serious metabolic complications, so that situation is a veterinary case, not a feed-store decision.

Make every ration change gradually over a week to ten days. That applies to hay changes as much as concentrate changes.

Reassess every two to four weeks with the tape, the scorecard, and photos. If nothing is moving after a month of genuinely increased intake, the problem is probably not the ration — go back to the diagnostic list.

Building a Forage Base That Supports Condition

Most weight-gain plans succeed or fail on the hay, because that is where the volume and the chew time come from. A better bale often does more than a more expensive bag.

Horse Creek Hay & Feed grows and supplies forage from Rocky View County with delivery across much of Alberta. You can browse what we have available this season to see formats and types, including options suitable for horses needing to gain.

Getting a hay analysis is worth it for a hard keeper. Knowing the actual energy and protein content of your forage tells you how big the gap really is before you start buying supplements to fill it.

If you want to talk through what forage would suit a thin horse — or a senior that can no longer manage long-stem hay contact our team and tell us what you are working with.

Conclusion

The best horse feed for weight gain is rarely a bag of grain. It is more forage, better forage, and then calories from fat and digestible fibre added carefully on top.

Before changing anything, find out why the horse is thin. Dental disease, ulcers, parasites, endocrine problems, and herd dynamics account for a large share of cases, and no ration fixes those.

Weigh what you feed, target at least 2 percent of body weight in forage, cap concentrate meals at around 0.5 percent of body weight, and give it at least sixty days.

Above all, respect the calendar. In Alberta, condition built in September is what carries a horse through February — and a severely thin horse needs a veterinarian before it needs a feed plan.

Frequently Asked Questions

Can I just feed more grain to put weight on my horse?

It is the riskiest way to do it. Large starch meals are associated with colic, gastric ulcers, and excitable behaviour, and undigested starch reaching the hindgut disrupts fermentation.

If a horse needs more calories than forage provides, fat and digestible fibre deliver them with far less risk, and any concentrate should be split into meals no larger than about 0.5 percent of body weight.

How much oil can I safely add to a horse's feed?

Start very small a quarter cup or less daily and increase gradually over two to three weeks, since the digestive system needs time to adapt. Most horses tolerate moderate amounts well, but sudden increases cause loose manure and feed refusal. 

Because added fat raises oxidative demand, discuss vitamin E supplementation with your veterinarian or an equine nutritionist.

My horse eats constantly but stays thin. What now?

That pattern points toward a health issue rather than a calorie shortage. Dental disease, parasites, gastric ulcers, PPID, and malabsorption all allow normal or increased appetite alongside weight loss. Book a veterinary exam including a dental check and a fecal egg count before adjusting the ration further.

Does blanketing help a horse keep weight on in winter?

It can, by reducing how much energy goes into heat production but it is not universally beneficial. A dry, thick winter coat is effective insulation on its own, and a blanket that flattens the coat or gets wet can make things worse.

Blanketing tends to help most for clipped horses, thin horses, seniors, and animals without wind shelter.

Should I feed a senior feed to any older horse that needs weight?

Not automatically. Age alone does not determine what a horse needs dental function does. A twenty-five-year-old with good molars may do better on quality hay plus added fat than on a complete senior feed.

Check for quidding and have the teeth examined, then choose the format based on what the horse can actually chew.