Endoscopic examinations were made every other month through late summer and fall to determine the amount of mucus in the trachea of 107 racehorses. Mucus secretion increases in response to irritation and inflammation and therefore is an indicator that horses have inhaled dust, mold, and other airborne irritants. The horses were kept in three stables and trained by different trainers. The barns were of various designs that influenced ventilation and exchange of air.
The researchers measured the dust concentration in every horse’s stall three times each day. Particles of dust, mold, and pollen were generally most prevalent in stalls where windows were small and ventilation was poor. Areas with low air movement, such as in the center of a barn, had high levels of dust. Dust was also prevalent in places where air was constantly in motion but was not replaced by fresh air. This included roads, tack rooms, in stalls near doors, and other areas of frequent travel by horses, people, or vehicles.
Similar levels of inflammation were found in the lungs of horses in stalls with constant low levels of dust and areas with periodic higher dust levels. Horses housed in barns with excellent ventilation (exchanging indoor and outdoor air, not simply stirring up the air inside the barn) have the best chance to avoid airway inflammation from inhaled dust.
Yet, there are many ways you can cut down on barn dust to improve air quality, provide a clean stable and improve and maintain the respiratory fitness of horses and humans.
Hay is probably the biggest offender when it comes to stable dust because, really, there’s no such thing as dust-free hay. However, the way it’s fed and stored can have a big impact on dust levels in the horse’s environment.
• Every time a horse digs in to a flake or bale, he’s releasing dust, mould and tiny plant fibres into his “breathing zone” – the area around his nose. Soak hay for a few minutes to help prevent dust and mould from escaping when the horse starts to eat.
• Horses like to shake out mouthfuls of hay. Open hay flakes outside and “pre-shake” them so the horse doesn’t face the initial onslaught of dust. (And the dust that does escape will remain outside.)
• Feed hay on the ground – not from haynets or racks – to allow mucous drainage out the nose and to reduce the amount of dust and mould inhaled.
• Store hay in an area away from horses, preferably in another building, and not above stalls or in lofts.
• Avoid feeding round bales in paddocks or pasture. The harvesting process encourages dust formation in these bigger bales. Plus, horses love to nestle their noses into the bale’s centre, breathing in dust full-bore.
Ultimately, the best way to reduce your horse’s exposure to dust is to keep him outside 24-7 with shelter. However, in the UAE summer constant turnout isn’t practical. The following tips will help him live a dust-reduced life inside.
• Do provide as much turnout as possible.
• Remove the horse from his stall when you’re mucking out. Allow the dust to settle before returning the horse to the stable
• Use low-dust bedding. While most bedding creates dust to a certain extent, straw is the worst culprit. Shavings are a better option, or, if they’re available, shredded cardboard and paper.
• Minimize bedding use by switching to rubber mats or stall mattress systems.
• Airflow – letting the good air in and stale air out – is critical. Depending on the size and set-up of the barn, ventilation can prove as simple as opening doors and windows or can involve elaborate, engineered systems.
• Allow your horse to hang his head outside his stall so he can breathe fresh air.
Michigan State University researchers investigating exposure to dust particles in racehorses found levels were highest in the early mornings, when activity in the barns was greatest. The barns that were open, airy and had the least human activity had the lowest particle concentrations.
You can easily accomplish your barn tasks in a way that manages and minimizes dust around the barn.
• Sprinkle barn aisles with water before sweeping.
• Don’t use leaf blowers to clean aisles.
• Use concrete or other materials for aisle floors rather than dirt.
• Cobwebs hold dust. De-cobweb regularly using brooms, or better yet, wet mops, or pressure washers which will help prevent dust from escaping into the air. Industrial vacuums work well too.
• Only carry out the above tasks when horses are outside.
• Turn off tractors and other equipment when they’re in the barn, as they can kick up big plumes of dust (plus exhaust fumes exacerbate respiratory illness).
• Feeds, particularly those of low quality, can contain a great deal of dust. Cubed, pelleted and extruded feeds, as well as those mixed with molasses, are far less dusty.
• Store and prepare feeds in an area separate from horses.
• Grooming creates a lot of flying dust, so do it outside.
• If you must use fans, mount them off the floor to prevent dust from the ground from blowing around. Only use fans designed for agricultural and industrial purposes, as their motors are sealed to stop dust from entering and potentially causing burnouts and fires.
• Speaking of fire, dust is considered a highly flammable material. Regularly clean accumulation off lights, appliances, electrical panel boxes and outlets.
• Outlets and switch boxes should have dust- and water-tight covers and light fixtures should be dust- and moisture-resistant.
With diligence, elbow grease, thoughtful decisions and sound management, you can limit the grime, health issues and hazards associated with dust, making your barn a nicer, safer place to be.