Horses have long had respiratory diseases. Back in the 1800s horses were said to be winded or to have broken wind when they had respiratory difficulties. They were called “pipers” by horse dealers because of their loud breathing which was a result of struggling to move air through their lungs.  These horses were likely suffering from a common condition that is linked with decreased performance in horses today known as Chronic Obstructive Pulmonary Disease of COPD. This condition is commonly called heaves and has a strong allergic component.

The manner in which the horse breathes is responsible for the name. Horses with heaves can usually inhale normally but have trouble exhaling. These horses may actually contract their abdominal or flank muscles in extreme cases when they try to force the air out of their lungs. Along the rib margin through the flank the muscles will thicken if the condition is chronic causing what is called “heaves line” to be seen.

Bacterial parasitic and viral infections can all be responsible for this inflammatory airway disease in horses. Allergies might be a factor including the common allergies to grains grasses tree pollens flowers or airborne pollutants and chemicals. Changes in the passageways can result if repeated inflammation occurs and this is often not reversible.

Signs and Symptoms
There is a thickening of the muscular and fibrous tissues that line the large airways of the lungs in horses with heaves. Excessive mucus is often produced by affected horses. The size of the airway is a result of this combination which can make it hard for the horse to breathe.

The problem is already severe once the horse has difficulty breathing so this is why prevention and early diagnosis is very important. However it can be difficult to obtain early diagnosis. Samples of fluid and mucus from the large airways of the lungs can be tested and analyzed in suspected horses.

Preventing Heaves or COPD
Avoiding allergies and environmental toxins that might cause heaves is the best method of prevention. Progress has been made by researchers in the manner of learning what to avoid and how to manage horses with the problem better. Throughout a normal day the dust around a horse’s nose is often three times higher than the dust around factories according to a recent test.

The biggest culprits are hay and poor-quality processed grains. It is especially risky if you have hay that has been poorly cured or old hay. It is best that you open a bale of hay and shake out a flake or two first. If you find mold or dust or have several of the flakes sticking together then it may cause your horse respiratory problems.

On occasion horses can tolerate such irritants but susceptible horses will develop heaves if they face continual exposure. It is still a long way off before we will have the ability to detect which horses will develop heaves even though testing is starting to become more helpful. Prevention and treatment should remain the focus of emphasis.

One obvious help is by using good-quality hay and grain. Always consider where the dust is coming from. If possible you should avoid storing hay over the stalls. You can help reduce some dust by wetting the hay prior to feeding. Horses with heaves should be fed from the ground instead of a wall feeder. Wall feeders keep the dust and hay near a horse’s nose while hay on the ground allows the horses to avoid the dust and get the added benefit of gravity which keeps the majority of the dust particles out of their lungs.

Feeding with hay cubes pellets and complete feeds can help reduce the dust for the horses that already have airway diseases. It is also important to pay attention to air circulation in barns you should make sure they are kept open and that the dust is reduced to a minimum. Another option to consider is replacing dusty shavings with shredded paper bedding. The best management you can use is to keep horses outside in the fresh air as much as possible.

Treating Heaves or COPD
There are two phases to approach in the treatment of heaves. Drugs called bronchodilators are usually used for immediate relief in horses with heaves. These products allow the smooth muscles in the lung airways to relax. Almost immediately this makes breathing easier for horses although it doesn’t have any curative effect on the process of the disease. Additionally there is a new face mask that is used to allow horses to breathe in a mist of drugs from an inhaler. Despite the fact that the mask looks uncomfortable and not easily tolerable by horses it actually provides them immediate relief and horses will quickly learn to accept the mask and the blast of medication from the inhaler. One successful antihistamine treatment option is the use of Tri-Hist.

However these drugs are not used for long-term use. Rather corticosteroids such as Dexamethasone are used for maintenance treatment. It will take a few days to a week or so for the steroidal anti-inflammatory drugs of NSAIDs to take effect and the results can vary between the horses.

While specific offensive toxins cannot always be eliminated from the horses world knowing what to avoid can help immensely.