Lower Airway Disease in Horses

November 10, 2008 (published)

Respiratory disease is fairly common in horses and can have a serious effect on a performance horse as well as a horse at pasture. The horse's respiratory system is divided into two parts, the upper and lower airways. The upper airway is the nasal cavity, throat, and trachea; the lower airway is the bronchi in the lungs and the lungs themselves.

Today on the program I am going to talk about disease that affects the lower airways. There are two main syndromes. Inflammatory airway disease is common in young athletic horses while recurrent airway obstruction or heaves is common in older horses. It's usually related to allergic disease. Clinical signs of inflammatory airway disease include coughing, excess mucous in the trachea, and poor performance. Clinical signs of heaves include coughing but also include increased lung sounds, increased respiratory efforts, and severe exercise intolerance. Horses with heaves usually have flared nostrils as they have a difficult time getting air. Both of these conditions can be treated with the same medications and one option is to treat them with metered dose inhalers that are manufactured for people with asthma. Of course, part of the problem is getting the medicine in horses as they will not breathe on command. There was a product on the market called an equine AeroMask that worked very well but was expensive. Now there is a new product called an AeroHippus that is much less expensive and the company indicates it even is more effective. If you have a horse with respiratory disease, contact your vet about using inhalant therapy with an AeroHippus aerosol chamber.

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