5 September 2022

Coughing in horses: causes, management and prevention advice

Stabled horses need forage and an enriched environment

Winter is a common time for horses to cough because they’re inside so much, and this is especially true if they’re in barn-style stabling, which pre-disposes them to spreading infection. This is exacerbated by the fact that colder temperatures and condensation make horses more prone to picking up a respiratory infection, so air quality is a major consideration when taking care of a horse in winter.

The causes of winter coughs in horses tend to be either environmental or an infection, but in a small number of cases there can be a viral cause. Environmental causes include dust, mould or spores from hay or bedding, which get into the lungs and cause inflammation in the lower airways, leading to coughing or causing irritation that allows infections to set in.

A horse coughing could be a sign of something more serious, such as respiratory disease — chronic obstructive pulmonary disease (COPD) also known as recurrent airway obstruction (RAO) — or equine asthma. Infections (often streptococcal) can be spread through coughing or sneezing when animals are sharing air space, especially if there’s not enough air turnover. Low temperatures cause horses’ expirations to form very small droplets, which can find their way deep into the lungs.

Larger droplets found in warmer weather can be filtered by the turbinates within a horse’s nose and head. Phlegm or snot produced by an affected horse can spread infections, and viruses such as influenza can also be spread this way.

Horse coughing during exercise

If a horse coughs at first and then appears fine the cause is likely to be environmental, but if the coughing persists it usually signals the presence of an infection.


If you find phlegm outside your horse’s door or on the floor of the stable it’s likely they have a productive cough as the result of an infection within the lungs.

Signs of general ill-health

A horse who appears depressed, is off their food or has a high temperature may well have a respiratory infection

Nasal discharge

Nasal discharge can be the sign of a problem. Here’s what’s normal and what’s not:

  • Clear or white discharge: Don’t worry just keep an eye on the horse’s breathing.
  • Yellow discharge out of both nostrils: This could be anything from an allergy to strangles, it depends on the rest of your horse’s symptoms. If your horse is under the weather, call your vet.
  • Yellow discharge out of one nostril: Usually a sinus infection or tooth abscess, call your vet.
  • Green discharge: A rather advanced infection probably from somewhere in the respiratory tract.

How to prevent your horse coughing

Reduce the chance of your horse contracting any respiratory diseases these quick tips:

1 Consider what horse bedding you use

Is your bedding dust free and how often do you take out the wet? You don’t want to be cleaning it all out too frequently if it’s shavings because the wet prevents dust from forming. If your horse is susceptible to dusty bedding, have a look at alternatives to straw which claim to be virtually dust free.

You should also avoid mucking out with your horse in the stable. Tie them up outside or put them into a different stable for 10 minutes. Don’t sweep the yard around them either and let fresh bedding settle before you move your horse back into their stable, as there will be dust particles in the air.

2 Soak or steam hay

Soak hay for five minutes to avoid the risk of your horse inhaling dust. You should also feed it to your horse immediately after soaking. A lot of people make the mistake of soaking hay in the morning then feeding it to them at night. Doing this is nearly worse than not soaking it at all because while the hay sits there, slightly damp all day, it’s the perfect environment for microbes to grow.

3 Consider a hay steamer

Hay steaming is scientifically proven to kill all dust spores in hay, helping to prevent respiratory problems. Soaking has previously been the conventional method to dampen down the spores, but it doesn’t remove them completely. Also, when feeding a horse out of a haynet, the hay dries out encouraging the spores to become airborne again.

4 Make sure there’s good ventilation

Your horse’s stable should have plenty of ventilation and, if possible, not be stabled near the hay or straw room. You can gauge how well ventilated your stable is by looking for cobwebs. Spiders don’t like ventilation so if they’re sharing your stable, chances are your horse could do with a bit more air.

Horses who are stabled in a barn will benefit from the main barn door being left open for a steady flow of fresh air, and if their stable has a window to the outside and you’re ever tempted to close it — don’t! The lack of ventilation that closing it will cause is more of a concern than the wet, windy weather.

5 Avoid sweeping around your horse

We all love a well-kept yard, but every time you do it you’re causing your horse to breathe in dust. Wait until your horse is away from their stable before you reach for the broom. A bit of dirt on the ground is better than irritated lungs.

6 Turn your horse out

The simplest and best thing you can do to prevent and manage coughing is turn your horse out as much as possible. Then they are well away from any dust and their head is down in a natural grazing position, helping their airways to clear.

This is why it’s always better to feed your horse off the floor in their stable too, rather than in a hay net. When they have their head down in a natural grazing position it allows their airways to drain more efficiently.

Your Horse

by Your Horse

Your Horse talks to hundreds of thousands of people around the globe who have one thing in common: they all love horses. Your Horse magazine, which prints 13 issues a year, has been a leading monthly equestrian title since 1983. Through its website, print and social media channels, Your Horse informs and entertains horse owners, riders and enthusiasts who want to do their very best for their horses.

The perfect gift...From just £37.99
Get a free Le Mieux Hat Silk when you subscribe!

Subscribe to Your Horse and save 19%, plus receive a free Le Mieux Hat Silk worth £22.95!