Why Is My Horse Eating Poop? Coprophagy Explained

Name: Why Is My Horse Eating Poop? Coprophagy Explained
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-02

Why is my horse eating poop? In most cases, this is normal behavior for young foals, but when an adult horse eats manure it usually points to a diet problem, boredom, or an underlying gut issue. The good news is that coprophagy is rarely dangerous on its own, and most cases can be corrected once you find the trigger.

This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

Foals eating their mother's manure is normal and expected. It helps seed the gut with fiber-digesting bacteria [1].
Adult horses may eat manure because of low forage, a bland or unbalanced diet, boredom, or stall confinement.
Coprophagy is common in juveniles across many species and appears to support gut development [2].
A sudden start in an adult horse deserves a veterinary exam to rule out ulcers, dental pain, or poor digestion.
Punishing the behavior does not work. Fix the diet, forage access, and environment instead.

Is It Normal for Horses to Eat Poop?

For foals, yes. Coprophagy is a normal and healthy part of early development. One study found that foals began eating manure as early as 3 days after birth, and every foal in the study was doing it by 7 days of age [1]. The researchers also found strong links between manure eating and the numbers of fiber-digesting bacteria in the foal's gut, which suggests the behavior helps populate the digestive tract with the microbes a horse needs to break down forage [1].

This pattern shows up in other species too. In ostrich chicks, eating adult feces helped mature the juvenile gut microbiota, and the behavior is especially common in young animals [2]. So if you have a foal nibbling at mom's manure pile, you are watching a normal developmental process, not a problem.

For adult horses, the picture changes. A healthy adult horse with good forage, turnout, and company has little reason to eat manure. When an adult starts doing it, that is your cue to look for a cause.

Why Does My Horse Eat Poop? The Common Reasons

Diet Problems

The most common driver in adult horses is a diet that does not meet the horse's needs. Horses are designed to eat forage almost constantly. When hay is limited, low in quality, or the horse is on a high-grain diet with little long-stem fiber, manure can start to look interesting.

Diet also changes the physical nature of manure itself. A study of healthy adult horses found that diet affects fecal dry matter and fecal particle size, with different diets producing different manure consistency and fiber digestibility [3]. When manure is softer or contains undigested material, a horse may be more inclined to pick at it.

Low forage intake is the number one thing to check. If your horse is stalled for long stretches with an empty hay net, that is a strong suspect.

Boredom and Confinement

Horses are grazing animals. A horse with nothing to do will find something to do, and manure is often within reach. Stall confinement, small dry lots, and long stretches without hay or social contact all raise the odds of this behavior.

Boredom-driven coprophagy tends to be more common in stalled horses and in horses kept alone. It often stops once the horse has more turnout, more forage, and more to occupy its time.

Gut and Digestive Issues

When digestion is off, manure may pass with undigested nutrients that make it appealing. Horses with gastric ulcers, dental problems that reduce chewing, or poor fiber fermentation may show coprophagy along with other signs.

If your horse has runny poop, that is a separate but related concern. Loose manure can signal a diet change, parasite load, sand, or an infection, and it can also make coprophagy more likely because the manure is softer and easier to consume. Runny manure in an adult horse is worth a veterinary call, especially if it lasts more than a day or two.

Nutritional Gaps

Some owners report that manure eating drops off once the diet is balanced for forage, minerals, and salt. This is not a guaranteed fix, but it is a reasonable place to start. A hay analysis and a ration review can reveal gaps you cannot see by eye.

Medical Causes to Rule Out

Before you assume this is behavioral, have your veterinarian check for medical triggers. These include:

Gastric ulcers, which are common in performance horses and can drive pica-like behaviors
Dental disease that reduces chewing efficiency and fiber breakdown
Parasite burden, especially in horses with limited deworming history
Hindgut imbalance or poor fiber fermentation
Sand accumulation, which can irritate the gut and change manure
Pain or stress from any source

A veterinary exam with a fecal test, dental check, and a review of your feeding program will sort most of these out. If your horse has other signs like weight loss, colic episodes, poor coat, or changes in appetite, mention those during the visit.

When Does Eating Poop Become a Problem?

Coprophagy is mostly a management issue, not an emergency. It becomes a problem when:

It starts suddenly in an adult horse that never did it before
It comes with diarrhea, weight loss, or colic
The horse is eating large amounts, not just nibbling
It leads to parasite exposure or spreads disease between horses
It signals a diet that is not meeting basic needs

Parasite risk is real. Manure is how many internal parasites complete their life cycle, so a horse that eats manure has more exposure. Keep a regular deworming plan in place and talk to your veterinarian about fecal egg counts.

Disease transmission is another consideration. In wildlife, researchers have raised concerns that coprophagy could increase the spread of parasites and pathogens between animals [4]. The same logic applies in a barn. If one horse has an infectious gut problem, manure eating can move it around.

What to Do Step by Step

1. Increase Forage

Offer free-choice or near free-choice hay, and use slow-feed nets if your horse eats too fast. Forage is the foundation of a horse's diet and the first thing to fix.

2. Review the Diet With Your Veterinarian

Ask for a ration review. A hay analysis plus a balanced vitamin and mineral supplement often closes the gaps that drive manure eating. Your veterinarian can calculate any needed amounts based on your horse's weight and health.

3. Add Turnout and Company

Horses are herd animals. More turnout, a compatible pasture mate, and room to move reduce boredom dramatically. If full turnout is not possible, increase the number of small meals and add enrichment.

4. Provide Enrichment

Slow-feed hay nets, multiple hay stations, and safe toys can give a stalled horse something to do. Rotate items so they stay interesting.

5. Manage the Manure

Pick stalls and paddocks frequently. The less manure your horse can reach, the less it can eat. This also cuts parasite exposure.

6. Rule Out Medical Causes

Schedule a veterinary exam if the behavior is new in an adult horse or comes with any other sign. Treating an ulcer or fixing a tooth may resolve the behavior on its own.

If you also have dogs at home, some of the same principles apply. Our guide on why dogs eat poop covers the canine side of this behavior, and how to stop a dog from eating poop walks through practical solutions.

What Not to Do

Do not punish your horse for eating manure. Punishment does not teach a horse what to eat instead, and it can create fear and handling problems. It also does nothing about the underlying cause.

Do not assume your horse is missing a specific nutrient and start adding random supplements. Guessing wastes money and can unbalance the diet further. Get a hay analysis and a professional ration review instead.

Do not ignore a sudden change in an adult horse. A horse that never ate manure and suddenly starts may be telling you something is wrong.

Do not confuse this with grass eating. Horses eat grass for many reasons, and the two behaviors have different causes. If you want to compare across species, our article on why dogs eat grass explains the range of normal and abnormal reasons animals eat things they should not.

When to Involve a Veterinarian or Behavior Professional

Call your veterinarian if:

An adult horse starts eating manure for the first time
The behavior comes with diarrhea, weight loss, colic, or poor appetite
You cannot get the behavior to stop with diet and management changes
You suspect ulcers, dental pain, or parasites
Your horse is eating manure in large amounts

A certified equine behavior professional can help if medical causes are ruled out and the behavior persists. They can assess stall design, turnout schedules, and social grouping to find practical fixes.

Limitations and When to Contact a Veterinarian

This article gives general guidance, not a diagnosis. Every horse is an individual, and individual cases need a veterinarian who can examine your horse, review the diet, and run any needed tests.

Contact a veterinarian the same day if your horse has diarrhea that lasts more than 24 hours, shows signs of colic (pawing, rolling, looking at the flank, not eating), or seems depressed or painful.

Treat it as an emergency now if your horse is rolling violently, cannot stand, has a distended abdomen, or has severe unrelenting pain. These are signs of a serious gastrointestinal emergency.

Schedule a routine visit if the behavior is new in an adult horse, if you want a diet review, or if you need a deworming and fecal egg count plan.

Frequently Asked Questions

Is it normal for horses to eat poop?

It is normal for foals and abnormal for most healthy adult horses. Foals eat manure to help colonize their gut with fiber-digesting bacteria, and nearly all foals do it within the first week of life [1]. Adult horses that eat manure usually have a diet, boredom, or medical trigger.

Why does my horse eat his own poop?

A horse may eat his own manure when forage is limited, when he is bored in a stall, or when digestion is incomplete and manure still contains appealing material. Diet affects manure consistency and fiber digestibility, so a change in feed can change the behavior [3]. Start with more forage and a veterinary diet review.

Why is my horse eating other horses' poop?

Horses may eat manure from pasture mates for the same reasons they eat their own, especially when forage is scarce or the herd is crowded. Shared manure also raises parasite and disease exposure between horses [4]. Pick paddocks often and keep a regular deworming plan.

Why does my horse have runny poop?

Runny manure can come from a sudden diet change, too much grain, parasites, sand, stress, or infection. Diet is a known factor in manure consistency and fiber digestibility in healthy horses [3]. If loose manure lasts more than a day or two, or comes with colic or fever, call your veterinarian.

Can eating poop make my horse sick?

Manure eating can increase exposure to parasites and pathogens, which is a concern researchers have raised in wildlife [4]. In healthy dogs, coprophagy did not change core gut bacteria or increase carriage of common enteropathogens [5], but that finding is specific to dogs and should not be assumed for horses. Keep up with deworming and fecal testing, and call your veterinarian if your horse shows signs of illness.

References

The Establishment of Fibrolytic Bacteria in the Foal Gastrointestinal Tract Is Related to the Occurrence of Coprophagy by Foals. Animals : an open access journal from MDPI, 2023.
Coprophagy rapidly matures juvenile gut microbiota in a precocial bird. Evolution letters, 2023.
The effects of diet on the physical characteristics of feces and fiber digestibility in healthy horses. Journal of animal science, 2026.
Coprophagy in moose: A first observation. Ecology and evolution, 2023.
Coprophagy in Healthy Dogs Does Not Alter Fecal Core Microbiota or Increase Carriage of Enteropathogens. Animals : an open access journal from MDPI, 2026.