Heaves in Horses

Horses' respiratory systems are very similar to human respiratory systems with a few 

differences: just for example, horses don't breathe out of their mouths. However their 

respiratory systems do serve basically the same purpose as ours. The respiratory tract 

takes in oxygen to the lungs to be exchanged with red blood cells for the oxygen to be 

used throughout the body. The respiratory tract is also responsible for clearing the 

system of irritants such as dust, bacteria, and fumes. It does this by trapping these 

irritants in a mucus that covers the airway. An over exposure to irritants can lead a 

horse to have some respiratory issues. Respiratory issues tend to present themselves 

with symptoms such as excessive nasal discharge, coughing, sneezing, or mucus secretions. 

   

As we all know, there can be a lot of dust in a barn from a variety of sources such as 

hay, feed, bedding, the horses backs and hooves as well as what people drag in. Dust 

can have molds, bacteria and other particles that can affect horses (and people’s) airways. 

   

Recurrent Airway Obstruction (RAO), also known as Chronic Obstructive Pulmonary 

Disease (COPD) or also simply called “heaves'' is a noninfectious respiratory disease 

that causes constriction of the lower airways and the accumulation of mucus. When a 

horse has heaves their lung tissues become inflamed and thick. This in turn decreases 

the elasticity of the lungs making breathing more labored.

Heaves presents itself much like other respiratory illnesses which can make it hard to 

be immediately diagnosed. Some of the signs of heaves are coughing, nasal discharge, 

labored breathing, reduced performance, flaring nostrils, and a “heave line”. 

A “heave line” is a line that begins to develop after a period of time where the horse’s 

exhale takes just as much energy as an inhale.

Unfortunately, heaves is not a curable illness and it is progressive and regenerative; 

meaning it will not go away and will tend to get worse in waves. However there are 

some practices and medicines out there to help manage heaves in horses. One of the 

key things to do when you have a horse with heaves is to cut down on dust as much 

as possible. You can change over to less dusty feeds or wet down horses feed to 

prevent inhalation of dust, switch to a less dusty bedding such as pine pellets, and try 

to take horses with heaves out of the barn when sweeping or cleaning stalls.  As far as

medications, there are Bronchodilators out there that can be administered orally or 

inhaled as an aerosol through a mask. In addition, there are corticosteroids for reducing 

inflammation. However, long term use of that medication can cause laminitis or 

infection. There are also traditional Chinese remedies available through your vet. 

While it is unfortunate that heaves is not curable, it does not mean the end of the horse's 

life. If  you have a horse present with heaves like symptoms, call your vet and develop 

a plan that works for you and your operation and do your best to make the horse 

comfortable. If you do not have horses that present with heaves, it may still be wise to 

adopt some of the dust minimizing practices to help ensure that your horses stay free of 

heaves and any other respiratory illnesses.

Heaves – The Horse Version of COPD | Panhandle Agriculture

Equine Respiratory Diseases

Written by Emily Jacobs, Bladen Extension Intern