Heat stress is a primary concern during the summer, yet a less obvious challenge some horses might face is maintaining respiratory health. Similar to humans, horses experience respiratory discomfort in the heat and humidity. A thorough understanding of equine respiratory health and its effective management during warmer months is essential.
This knowledge can help keep horses’ respiratory systems in ideal condition even if they are prone to equine asthma.
Imagine an athlete after a marathon, their chest rising and falling with heavy, effort-laden breaths. Now, picture this scenario in the equine world during the heat of summer. Horses are not mere spectators of their surroundings; they actively inhale the warm air, often filled with particulates, which poses a potential risk to their sensitive respiratory systems.
Studies state that horses suffering from respiratory ailments might exhibit subtle signs, like reduced performance, chronic coughing, or even nasal discharge. Identifying these indicators early is of great importance. Conditions such as inflammatory airway disease (IAD) or recurrent airway obstruction (RAO), casually known as “heaves,” can flare up under summer conditions, jeopardizing the well-being of the horse.
According to Dr. Christine Cocquyt Montgomery, DVM, DACVIM with Tennessee Equine Hospital Main, “Heaves is a commonly recognized respiratory issue in horses. Now termed “Equine Asthma,” this inflammatory condition involves airway reactivity to allergens like dust, mold, and pollen. The underlying physiological changes are similar to human asthma with constriction of the small airways in the lungs and increased production of mucus in the airways. The classic form of Equine Asthma occurs in horses in stalled environments where exposure to dust and fungal spores from hay tend to be higher. Moving those horses outside is often helpful. Here in the South however, we commonly see a different version of this syndrome called Summer Pasture-Associated Equine Asthma (SPAEA) in which horses react to the heavy pollen, heat, and humidity.”
The summer cocktail for respiratory discontent is a fusion of airborne irritants (dust, sand, pollen), hazardous gasses (pathogens, mites), and physical stressors (high temperatures, humidity, strenuous exercise). This medley not only reduces the airflow and oxygen exchange but also incurs long-standing challenges that transcend the summer months.
By knowing potential risks and causes, it’s important to focus on preventative and soothing strategies. In a multi-pronged approach horses can sustain and thrive. It is best to practice a diverse mixture of environmental management, nutritional adjustments, and better Equine Management Practices (EMP) overall.
Dr. Montgomery states, “The first signs of SPAEA may be an occasional cough or increased respiratory effort especially when out grazing or being ridden during the summer months. In early cases, the signs often resolve with the onset of fall and cooler weather. Less severe cases are often managed by moving the horse into a barn with fans or climate control. The respiratory tract in these horses may be ‘hyper reactive,’ so decreasing dust in the environment and feeding clean soaked hay and feed may also be necessary. More severe cases may exhibit flared nostrils, extended neck, and an abdominal push with breathing. The abdominal push eventually causes enlargement of the muscles along the edge of the ribcage commonly known as the ‘heave line.’ Equine Asthma is a progressive condition that may eventually lead to the horse having year-round signs of labored breathing and cough that is difficult to control. Horses with Summer Pasture-Associated may not tolerate riding during the Summer months.”
It is important to note that horses with uncomplicated Equine Asthma should not have a fever, swollen lymph glands, or a lot of nasal discharge. If these symptoms are present then it is best to quarantine the horse and call your veterinarian.
Kyla Szemplinski, MS, Extension Agent with UT and TSU Shelby County Extension office also recommends, “Horses sensitive to bedding should be moved to a pasture, but if the horse is suffering from allergens from the pasture, they should be moved in a stall with low-dust bedding such as shredded paper or cardboard.”
In the barn, it’s crucial to ensure proper ventilation. As recommended, moisten feeds to reduce dust, and maintain a constant watch on air quality indexes to achieve significant improvements. Simple measures, such as having cooling fans in the stables, watering the arena to minimize dust and rescheduling rides to cooler periods can make a substantial difference.
“In addition to environmental changes and soaking feed, some cases require medications that help open the airways and decrease inflammation. These can be administered systemically or through a nebulizer. Your veterinarian can help determine the best treatment plan for each individual horse,” Dr. Montgomery states.
Considering the role of diet, ensuring an uptake of good-quality forages, like dust-free hays, and adding vitamin E for its antioxidant properties can help bolster the horse’s immune response and respiratory function. Dr. Montgomery recommends, “Maintaining a healthy body condition in your horse may help them handle the heat and humidity better. Some studies have shown that omega-3 fatty acid supplementation improves the inflammatory response in respiratory conditions as well.”
While it’s tempting to push through the summer’s heat with a regular exercise regimen, dialing down the intensity, increasing cool-down periods, and incorporating breaks are indispensable. Research has underscored the importance of the role of oxidative stress in respiratory disease in horses. By taking advice from veterinarians and applying them, caretakers and horse owners can help their horses sustain throughout the hot, summer months without complications.
