EquineHow to Help a Hard Keeper Gain Weight: A Practical Guide
Some horses seem to eat everything and still look ribby. "Hard keepers" are common, especially among Thoroughbreds, Arabians, young horses, seniors and busy performance horses. The key is finding out why before adding feed, then adding calories safely.
- Rule out health causes first: teeth, parasites, ulcers, pain and illness.
- More or better hay is usually the safest first step.
- Fat and digestible fiber add calories without large amounts of starch.
- Make changes gradually and keep grain meals moderate in size.
- Track weight and body condition every couple of weeks to see what's working.
Step 1: find out why
Weight loss or poor weight gain usually has a cause. Ask your vet to check:
- Teeth: sharp points, missing teeth or pain make chewing inefficient.
- Parasites: a fecal egg count shows whether worms may be a factor.
- Gastric ulcers: common in performance horses and horses under stress.
- Pain: lameness or discomfort can reduce appetite.
- Illness: liver, kidney or other conditions, and PPID in older horses.
- Herd dynamics: a low-ranking horse may be pushed off food.
Once health issues are addressed, many horses gain weight on the same diet.
Step 2: understand calorie needs
Horses need more calories when they:
- Work harder or more often
- Are growing, pregnant (late term) or nursing
- Live in cold, wet or windy weather, especially if clipped or thin
- Are nervous or always on the move
Use body condition scoring and a weight tape every couple of weeks so you can see whether changes are working.
Step 3: start with forage
Forage is the safest calorie source for most horses and supports gut health. Common approaches include:
- More hay, or free-choice hay if appropriate
- Higher-quality hay, often leafier and cut earlier, which supplies more energy and protein
- Adding alfalfa or an alfalfa mix, which is higher in calories and protein
- Hay cubes or pellets for horses that waste hay or have dental issues
A hay test shows how much energy your hay actually provides.
Step 4: add calories with fat and fiber
When forage alone isn't enough, many owners add energy from sources that are low in starch:
| Source | Why it's used | Notes |
|---|---|---|
| Vegetable oil | Very calorie-dense: a cup supplies roughly 2 Mcal, about as much as 1.5 lb of oats | Introduce slowly; ask your vet how much |
| Rice bran (stabilized) | About 20% fat | Choose calcium-balanced products |
| High-fat feeds | Fat and fiber in one bag | Check fat %, starch and the feeding rate |
| Plain beet pulp | Digestible fiber energy | Usually soaked; check for molasses |
| Soybean hulls | Digestible fiber | Often in feeds already |
Fat-based calories are often a good fit for horses that get "hot" on grain or have ulcers or certain muscle conditions. Your vet can help choose.
What about grain?
Grain and sweet feeds add calories quickly, and some horses do well on them. But large starchy meals are linked to digestive upsets and ulcers. If grain is part of the plan, ask your vet how much per meal and how many meals per day. Splitting the daily amount into smaller, more frequent meals is common.
Change slowly and track progress
- Change one thing at a time so you know what works.
- Introduce new feeds and fat gradually. Many vets suggest transitioning over about 10–14 days; see the feed switch schedule tool.
- Weigh feed and hay, since scoops and flakes vary.
- Re-check body condition and weight every 2–4 weeks. Healthy weight gain takes time.
Questions to ask your vet
- Could teeth, parasites, ulcers or pain explain the weight loss?
- How much hay should my horse be getting?
- Would alfalfa, beet pulp or a higher-fat feed suit my horse?
- Is added oil or rice bran a good idea, and how much?
- How big should grain meals be, and how many a day?
- What's a realistic target weight and timeline?
In the Equine Feed Guide, tick "Hard to keep weight on" to see higher-fat, lower-starch feeds ranked first and fat supplements to discuss with your vet.
Frequently asked questions
What is the fastest way to put weight on a horse?
There isn't a safe shortcut. Rule out health problems first, then increase forage and add calories from fat and digestible fiber gradually, as your vet advises.
Is oil good for helping a horse gain weight?
Vegetable oil is very calorie-dense and is often used to add calories without starch. Introduce it slowly and ask your vet how much suits your horse.
Does beet pulp help horses gain weight?
Beet pulp provides digestible fiber energy and is commonly used for hard keepers. Plain, unmolassed beet pulp is low in sugar and is usually soaked before feeding.
Why is my horse losing weight even though it eats a lot?
Common causes include dental problems, parasites, ulcers, pain, illness and herd competition. Ask your vet to check before increasing feed.
How long does it take a horse to gain weight?
It usually takes weeks to months. Track body condition and weight every few weeks to see progress.
Sources and further reading
- National Research Council. Nutrient Requirements of Horses, 6th revised edition (2007).
- American Association of Equine Practitioners (AAEP): owner resources on weight loss and nutrition.
- University extension horse programs on feeding underweight horses.
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