The severe fires throughout Western Canada and the US have exposed humans and animals to unhealthy air containing wildfire smoke and particulates (updated 05 SEPT 2018)
Air Quality Health Index (AQHI)
Government of Canada... Air quality is critical to our health. The Air Quality Health Index (AQHI) is a tool to help you plan and enjoy a healthy lifestyle. Much like the UV Index helps protect us from the harmful effects of too much sun, the AQHI alerts us to health risks posed by air pollution.
The AQHI is for everyone, including those vulnerable to the effects of air pollution, like seniors, people with chronic illnesses, or parents of young children. It has been designed to help you decide the best time to enjoy your outdoor activities. The AQHI is measured on a scale ranging from 1-10+
Guidelines for Horses Exposed to Wildfire Smoke
UC Davis Veterinary Medicine... How Smoke Affects Horses
The effects of smoke on horses are similar to effects on humans: irritation of the eyes and respiratory tract, aggravation of conditions like heaves (recurrent airway obstruction), and reduced lung function. High concentrations of particulates can cause persistent cough, increased nasal discharge, wheezing and increased physical effort in breathing. Particulates can also alter the immune system and reduce the ability of the lungs to remove foreign materials, such as pollen and bacteria, to which horses are normally exposed.
Protecting Horses from Air Pollution
Limit exercise when smoke is visible. Don’t have your horse do activities that increase the airflow in and out of the lungs. This can trigger bronchoconstriction (narrowing of the small airways in the lungs).
Provide plenty of fresh water close to where your horse eats. Horses drink most of their water within 2 hours of eating hay, so having water close to the feeder increases water consumption. Water keeps the airways moist and facilitates clearance of inhaled particulate matter. This means the windpipe (trachea), large airways (bronchi), and small airways (bronchioles) can move the particulate material breathed in with the smoke. Dry airways make particulate matter stay in the lung and air passages.
Limit dust exposure by feeding dust-free hay or soak hay before feeding. This reduces the particles in the dust such as mold, fungi, pollens and bacteria that may have difficulty being cleared from the lungs.
If your horse is coughing or having difficulty breathing, have your horse examined by a veterinarian. A veterinarian can help determine the difference between a reactive airway from smoke and dust versus a bacterial infection and bronchitis or pneumonia. If your horse has a history of having heaves or recurrent airway problems, there is a greater risk of secondary problems such as bacterial pneumonia.
If your horse has primary or secondary problems with smoke-induced respiratory injury, you should contact your veterinarian who can prescribe specific treatments such as intravenous fluids, bronchodilator drugs, nebulization, or other measures to facilitate hydration of the airway passages. Your veterinarian may also recommend blood tests or other tests to determine whether a secondary bacterial infection has arisen and is contributing to the current respiratory problem.
Give your horse ample time to recover from smoke-induced airway insult. Airway damage resulting from wildfire smoke takes 4-6 weeks to heal. Ideally, plan on giving your horse that amount of time off from the time when the air quality returns to normal. Attempting exercise may aggravate the condition, delay the healing process, and compromise your horse’s performance for many weeks or months. While we recognize that owners and trainers of sport horses may want to return to work sooner than 4-6 weeks, Dr. Kent Pinkerton* recommends that horses return to exercise no sooner than 2 weeks post smoke-inhalation, following the clearance of the atmosphere of all smoke. Horses, like all other mammals, tend to have an irritation to particles, but will recover from the effects within a few days. With the devastation at San Luis Rey Downs (where 46 horses died, mostly from fire or smoke inhalation), it would be wise give the horses a break from exercise and then to gradually re-introduce them back to their routine exercise. On December 10, 2017, Dr. Rick Arthur, equine medical director at the UC Davis Kenneth L. Maddy Equine Analytical Chemistry Laboratory and at the California Horse Racing Board, issued an advisory on behalf of the CHRB regarding horses at the Del Mar racetrack.
Smoke From Wildfires and Horses’ Respiratory Health https://thehorse.com/149183/smoke-from-wildfires-and-horses-respiratory-health/
Wildfire Smoke and Horses - https://www2.vetmed.ucdavis.edu/ceh/local_resources/pdfs/currenthealth_wildfiresmoke.pdf
Fire and Smoke Inhalation Injury in Horses - https://oahn.ca/wp-content/uploads/2016/01/Fire-and-Smoke-Inhalation-injury-in-horses.pdf
Wildfire Smoke and Animals - https://www.avma.org/public/EmergencyCare/Pages/Wildfire-Smoke-and-Animals.aspx