My Horse Is Coughing. Should I Worry?

Horses, like people, do cough occasionally. But if your horse is coughing persistently and has symptoms like nasal discharge and labored breathing during exercise, that warrants attention—even if your horse doesn’t have a fever or hasn’t been exposed to sick horses recently.

Equine respiratory issues can crop up at any time of year—especially those caused by a respiratory virus or shipping fever (bacterial pneumonia). But breathing problems related to equine asthma can become more frequent or severe toward the end of winter, when horses and ponies have been exposed to more dust and allergens in hay, barns, stalls, and indoor arenas. If your horse is coughing but doesn’t have an elevated temperature, hasn’t traveled, and hasn’t been around a horse with a respiratory infection, your veterinarian might suspect equine asthma.

What Is Equine Asthma?

Equine asthma is a chronic inflammatory lower-airway disease that affects a horse’s ability to breathe normally. Similar to asthma in humans, it’s not infectious and is brought on by allergens and irritants in the environment that lead to inflammation and airway obstruction. Understandably, if your horse is coughing frequently, it will affect his ability to perform. In some cases, it can also contribute to exercise-induced pulmonary hemorrhage (EIPH), or bleeding into the airways while exercising, although EIPH is a respiratory issue that also can occur due to strenuous exercise.

There are two main forms of equine asthma:

 Mild to moderate equine asthma, formerly called inflammatory airway disease (IAD): More common in younger horses. It causes intermittent coughing and reduced performance but no obvious breathing distress when the horse is at rest.

Severe equine asthma, previously known as heaves or recurrent airway obstruction (RAO): Typically affects horses older than 7. It can lead to chronic coughing, exercise intolerance, nasal discharge, and difficulty breathing, even at rest.

A subtype of severe equine asthma, summer pasture recurrent airway obstruction (SPRAO), also can affect horses. It’s a seasonal respiratory issue, usually occurring in hot, humid conditions in summer.

Causes of Equine Asthma

Several environmental and management factors can contribute to respiratory problems in horses, including:

• Dust and mold spores from hay, bedding, and barn air
• Ammonia fumes from urine-soaked bedding
• Poor ventilation in barns and indoor arenas
• Cold, dry air in winter months
• Pollen and airborne allergens

Clinical Signs of Equine Asthma

If your horse is experiencing respiratory issues, you may notice:

• Chronic or intermittent coughing
• Nasal discharge (clear or white)
• Increased respiratory effort during exercise
• Flared nostrils at rest
• Reduced performance level, quick fatigue, or reluctance to work
• A “heave line”—a ridge along the muscles of the abdomen from overuse through breathing difficulty in severe cases

Diagnosing Equine Asthma

Your veterinarian probably will begin by conducting a thorough physical examination. She’ll also get a detailed history of the horse’s symptoms, environment, and management. Since environmental factors can contribute to respiratory issues, your veterinarian might also closely evaluate your horse’s living conditions, including barn ventilation, bedding, and hay quality. She also might perform these tests or procedures:

Rebreathing test: The vet places a plastic bag over the horse’s nose to encourage deeper breaths. This can amplify abnormal breathing sounds, making it easier to hear their particular characteristics, which can help point to a cause.

Bronchoalveolar lavage (BAL): BAL involves passing a small tube into the horse’s lower airways to collect fluid samples. The presence of inflammatory cells—particularly neutrophils, mast cells, and eosinophils—can indicate airway inflammation associated with equine asthma.

Treatment Options

Getting your horse’s breathing back to normal after a diagnosis of equine asthma often involves several combined approaches, including treatments tailored to your horse’s specific needs.

The first step is to improve his or her environment—think better ventilation, overall dust reduction, and more outdoor turnout—but not where the horse can eat round bales, which can worsen respiratory symptoms (see “Prevention” section below). For equine asthma, she also might prescribe bronchodilators to help your horse breathe more easily, along with anti-inflammatory medications if needed. In more severe cases of equine asthma, she might recommend corticosteroids to reduce inflammation relating to the lungs.

Medications like corticosteroids and bronchodilators can be effective for managing acute flare-ups of equine asthma, but their prolonged use can lead to complications including laminitis, immune suppression, and drug intolerance. So even with drug therapy, good management is crucial for reducing a horse’s exposure to dust and allergens. Supporting a horse’s airways from the inside out can help, too.

This can be done by adding AirWise™ to your horse’s feeding regimen. Research trials at the University of Georgia demonstrated the benefits of AirWise in helping horses return to normal respiratory function and maintain it. AirWise provides targeted respiratory support with a synergistic blend of potent antioxidants and micronutrients. These include resveratrol and other polyphenols, and citrus bioflavonoids. According to the research, the combination helps to

• maintain normal respiratory rates
• support a healthy inflammatory response in airways
• support immune health
• enhance lung function

Prevention

When it comes to equine respiratory issues like equine asthma, an ounce of prevention really is worth a pound of cure. Employ management practices that can reduce your horse’s environmental exposure to dust, allergens, and pathogens:

• Keep barns well-ventilated by opening windows and doors or using fans
• Feed hay from the ground, which allows a horse’s nasal passages to clear allergens more effectively
• Soak hay, use a hay steamer, or feed pelleted hay to reduce dust
• Use low-dust bedding options like cardboard or coir (derived from coconut husk)
• Turn out horses as much as possible to limit time in enclosed spaces
• If possible, turn out horses during stall-cleaning or when sweeping barn aisles

Keep an eye out for any early signs of respiratory distress. If your horse is coughing or showing signs of respiratory distress, don’t wait to see if it resolves on its own. Contact your veterinarian for proper diagnosis and treatment. Early intervention can lead to a better outcome and help prevent a chronic respiratory issue.