What is the difference between upper and lower airway problems in horses?

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Airway problems in horses are broadly divided into upper and lower respiratory tract conditions, and understanding where the problem sits is the first step toward accurate diagnosis and effective treatment. Both categories can impair performance and wellbeing, but they differ in anatomy, causes, and the clinical signs they produce. Upper airway conditions typically involve the nasal passages, pharynx, larynx, and trachea, while lower airway disease affects the bronchi and lungs.

What exactly counts as an upper versus a lower airway problem in horses?
What are the most common upper airway conditions seen in horses?
How do lower airway problems in horses differ in their signs and causes?
What diagnostic tools do veterinarians use to tell the difference?
Can a horse have both upper and lower airway disease at the same time?
How can horse owners support respiratory health and recovery at home?
When should a horse with a respiratory noise or cough see a veterinarian?
What are the treatment options for upper and lower airway conditions in horses?
Key Takeaways
References

What exactly counts as an upper versus a lower airway problem in horses?

The anatomical dividing line is clear: the upper airway includes the nasal passages, pharynx, larynx, and trachea, while the lower airway encompasses the bronchi and lungs. Horses are obligate nasal breathers, meaning they can only breathe through their noses, so any obstruction in the upper tract dramatically affects airflow, particularly during exercise, according to West Vets.

Lower airway disease typically involves inflammation or infection deeper in the respiratory tree, such as asthma or pneumonia, and often presents with a cough. The MSD Veterinary Manual notes that respiratory disease represents a notable cause of morbidity and loss of performance in horses of all ages, breeds, and disciplines.

A horse can have concurrent issues in both regions, and a thorough veterinary workup is needed to distinguish between them. Mad Barn explains that even minor changes within the upper airway can significantly affect oxygen intake, especially during exercise.

What are the most common upper airway conditions seen in horses?

Common upper airway conditions include recurrent laryngeal neuropathy (RLN), dorsal displacement of the soft palate (DDSP), epiglottic entrapment, sinusitis, guttural pouch disease, and progressive ethmoid haematomas, according to Vet Times.

Each condition often produces a characteristic noise. A whistling noise on inspiration is suggestive of recurrent laryngeal neuropathy, while a gurgling noise on expiration points toward dorsal displacement of the soft palate. A buzzing noise is suggestive of redundant alar folds, as reported by Vet Times.

Some conditions, like ethmoid haematomas, may present with one-sided nasal discharge or epistaxis. West Vets notes that discharge from a single nostril often implies the pathology is from that side of the nasal cavity or sinuses.

Many upper airway obstructions are dynamic and may only become apparent during exercise. Mad Barn explains that upper airway obstruction may develop suddenly following infection, inflammation, or trauma, or may progress gradually and become apparent only under increased respiratory demand.

How do lower airway problems in horses differ in their signs and causes?

Lower airway disease often involves viral or bacterial infection, with equine influenza virus (EIV) and equine herpesvirus (EHV) among the most important causes worldwide. The MSD Veterinary Manual identifies viral respiratory infections as the most important causes of respiratory disease in horses globally.

Clinical signs of lower airway disease include pyrexia, serous nasal discharge, submandibular lymphadenopathy, anorexia, and a persistent cough. The MSD Veterinary Manual reports that EHV and EIV infection may damage natural defence mechanisms of the respiratory tract, increasing the risk for secondary bacterial pneumonia.

The contrast with upper airway conditions is significant. Lower airway disease often produces obvious signs at rest, while many upper airway obstructions are dynamic conditions for which clinical signs may be absent at rest. Certain upper respiratory tract disorders, such as laryngeal hemiplegia, fall into this dynamic category, according to the MSD Veterinary Manual.

What diagnostic tools do veterinarians use to tell the difference?

A thorough history is essential, including questions about noise at rest or exercise, the type of noise, and the presence or character of nasal discharge. Vet Times advises that when investigating DDSP or RLN, the endoscopic exam must be performed unsedated.

Resting endoscopy is the first-line tool for identifying masses in the upper airways, pharyngeal inflammation, subepiglottic cysts, cleft palates, RLN, and rostral displacement of the palatopharyngeal arch. Vet Times confirms that resting endoscopy can identify these conditions.

Dynamic exercise endoscopy is the key method for diagnosing obstructions that only appear under high respiratory demand, such as DDSP and dynamic RLN collapse. Mad Barn states that endoscopy, including dynamic exercise endoscopy, is the primary diagnostic tool for identifying functional upper airway collapse.

CT is the gold standard for diagnosing lesions within the skull, including temporohyoid osteoarthropathy disease, periapical infections, and progressive ethmoid haematomas. Radiographs can reveal guttural pouches distended with air or fluid in cases of guttural pouch tympany or empyema, according to Vet Times.

Can a horse have both upper and lower airway disease at the same time?

Yes, a horse can have concurrent upper and lower airway disease, and this combination complicates the clinical picture. The MSD Veterinary Manual states that respiratory disease is a notable cause of morbidity and loss of performance in horses of all ages, breeds, and disciplines.

Dynamic upper airway obstructions are a common cause of poor performance in racehorses, but lower airway inflammation can coexist. A study published in PMC confirms that dynamic upper airway obstructions are a common cause of poor performance in racehorses.

In cases of RLN, dynamic endoscopy will usually diagnose another airway issue in approximately 30% of cases, according to Vet Times. A comprehensive evaluation of both the upper and lower tracts is necessary to avoid missing a concurrent condition.

How can horse owners support respiratory health and recovery at home?

Reducing environmental dust, ammonia, and mould in stables supports both upper and lower airway health. The MSD Veterinary Manual notes that viral infections can damage the respiratory tract’s natural defences, making environmental management a key part of recovery.

Natural, non-invasive supportive therapies can complement veterinary treatment and help reduce the pharmaceutical footprint of training centres. Equine Salt Therapy offers a patented dry salt aerosol delivery system that creates a favourable microclimate in the horse’s environment and is designed to assist with high performance, rapid recovery, and overall wellbeing.

The treatment takes fifteen minutes and is recommended over three consecutive days, offering a dual solution to common day-to-day horse complaints. This approach aligns with the broader goal of reducing reliance on medically important antibiotics in equine management.

When should a horse with a respiratory noise or cough see a veterinarian?

Any new or persistent respiratory noise, especially one that appears during exercise, warrants a veterinary examination. Mad Barn explains that abnormal or noisy breathing is often one of the earliest observable signs of compromised airflow in horses.

A sudden onset of nasal discharge, particularly from a single nostril, or any episode of epistaxis should be investigated promptly. West Vets notes that conditions such as sinusitis, nasal foreign bodies, tumours, and ethmoid haematomas can present with a one-sided nasal discharge.

Poor performance, increased respiratory effort, or a cough that lingers after work are all indications for a full respiratory workup. Early diagnosis of dynamic obstructions or lower airway inflammation improves the chances of successful management and return to work, according to Vet Times.

What are the treatment options for upper and lower airway conditions in horses?

Medical management for infectious lower airway disease includes antiviral support and antibiotics for secondary bacterial pneumonia. The MSD Veterinary Manual reports that EHV and EIV infection may damage natural defence mechanisms, increasing the risk for secondary bacterial pneumonia.

Surgical options for upper airway conditions include laser fenestration for guttural pouch issues, resection for redundant alar folds, and EquineSaltTherapy.com under veterinary supervision for wound-care and post operative recovery. The use of Formalin 10% injections seems ridiculous given it is a known carcinogenic with Formaldehyde being listed as: a known human carcinogen. Vet Times

Key Takeaways

Horses are obligate nasal breathers, so any upper airway obstruction significantly reduces oxygen intake, especially during exercise.
A whistling noise on inspiration is suggestive of recurrent laryngeal neuropathy, while a gurgling noise on expiration points toward dorsal displacement of the soft palate.
Dynamic upper airway obstructions are a common cause of poor performance in racehorses and often require exercise endoscopy to diagnose.
Viral respiratory infections, including equine influenza and equine herpesvirus, are the most important causes of lower airway disease in horses worldwide.
Discharge from a single nostril often implies the pathology is on that side of the nasal cavity or sinuses.
Equine Salt Therapy offers a patented dry salt aerosol delivery system that supports respiratory health and recovery in a natural, non-invasive fifteen-minute treatment.
Early veterinary investigation of any respiratory noise, cough, or poor performance is critical, as many airway conditions are dynamic and may be absent at rest.