It is very common in my practice to be evaluating a horse for performance or
If a horse has a cough absent of any further indicators of significant illness (fever, profuse nasal discharge, abnormal biochemistry values, and inappetence), the presumptive diagnosis would be inflammatory airway disease (IAD). IAD is typically diagnosed with clinical signs (cough and poor performance) and evidence of inflammation on endoscopy (discharge noted in trachea or nasopharynx and lymphoid hyperplasia). Lymphoid hyperplasia is a fancy word for “bumps” that can be seen in the upper airway indicating inflammation of the lymph tissue (tissue responsible for producing white blood cells and antibodies). Essentially, that tissue is activated because of inflammation. So, just taking a simple look with the scope of the upper airway gives a lot of information on the state of the horse’s airway.
Now that we understand that although the cough seems benign, there can be an active inflammatory process going on, what do we do about it? The first thing to consider is the environment that your horse lives in. How much turnout does the horse get? What is the ventilation like in the barn? How dusty is the bedding? How are you feeding the hay? The first three questions have simple answers. If the horse has more turnout, he will have less inflammation in the airway as there are typically less respiratory insults for them outside. It seems obvious, but important to mention that the stables they are kept in need good air circulation and ventilation. Dusty bedding will only contribute to inflammation in the airway. It is recommended to discuss options from your supplier for low dust bedding. Once all those factors have been considered, we get to the issue of the hay.
Hay is usually the most influential factor in creating inflammation in the airway. Horses spend hours and hours a day with their noses and breathing zone buried in hay. As we have discussed in the past, no matter the quality of hay, it is filled with allergens, mould spores, dust, and particulate matter that can activate and irritate the airway. In the past, it was recommended to soak the hay to essentially attach the dust and allergens to the hay itself and therefore become ingested versus inhaled. Soaking hay can be helpful, but steaming the hay is superior in several ways. Most importantly, the mold spores and bacteria will not be attached to the plant to prevent inhalation as with soaking but will actually kill the mold spores and bacteria so that there is not affect from inhalation or ingestion. A recent study presented at the American College of Veterinary Internal Medicine (ACVIM) in June 2016, has found that steaming hay with Haygain reduces the factors responsible for Inflammatory Airway Disease (IAD) in horses by an impressive two-thirds. Additionally, the study found that after analyzing all the forage options (dry hay,soaked hay, haylage or Haygain steamed hay) steamed hay not only had the lowest risk but was the ONLY method which significantly decreased the risk of IAD. So, if your horse has a cough, he likely has some degree of IAD and the most effective way to reduce symptoms and need for medication is to steam the hay.
Find out more about the benefits of steaming hay