During the winter months, many horses are stabled for at least part of the day and are therefore exposed to a high level of dust and airborne particles in the environment.
Equine asthma (previously called ‘recurrent airway obstruction’ (RAO); ‘chronic obstructive pulmonary disease’ (COPD); ‘heaves’ or ‘broken wind’) occurs mainly as a result of exposure to dust, usually associated with stabling. Equine asthma results from a hypersensitivity response, especially to particles from mouldy or dusty hay and bedding. In most cases, the disease can be reversed by treating with bronchodilators, steroids and implementing changes to husbandry. For stabled horses, close attention to feed, forage and bedding is important as they are the main sources of dust.
The horse may only cough when ridden, or may cough in the stable, with or without nasal discharge. In mild cases, there may be no cough at all, but the horse may show exercise intolerance. To investigate the severity and cause of the cough we can perform a routine physical examination, then, depending on the severity of signs, may decide to perform an endoscopy with tracheal wash or bronchoalveolar lavage. This enables analysis of airway secretions, which helps to confirm the diagnosis, determine the most appropriate treatment and monitor the response to treatment.
Other common causes of coughs include infection with respiratory viruses (such as influenza) or bacterial infections (such as strangles).
Here are some things that you can do to reduce the risk of your horse developing a cough or to help with treatment if your horse develops a cough:
- Ensure that the stable has good ventilation so that dust is removed from the air rapidly – an outside stable is generally better than a barn if your horses is sensitive to dust
- Feed forage from the ground or a container on the floor rather than a haynet or high level hayrack
- Soak or steam hay (and only use good quality hay) or use horsehage / haylage as an alternative
- Bed on dust-extracted shavings or minimal dust bedding (although if your horse is stabled in a barn with other horses on straw, then the advantage of changing a single horse’s bed is negligible – if possible, ALL horses in the same airspace should be on the same dust minimal bedding
- Take the horse out of the stable when it is being mucked out and keep it out for at least 30 minutes
- Make sure that vaccination against equine influenza is kept up to date