Is turnout bad for horses with heaves?
Q:My daughter’s horse was recently diagnosed with pasture heaves. It took a long time to figure out because we were keeping him outside all the time— thinking the fresh air would do him good— but he only got worse. In the autumn and winter his breathing is fine, indoors and outdoors. The veterinarian explained that this horse is sensitive to mold and pollen, so I should plan on keeping him in all summer next year. That seems like it could cause other problems. Are there medications make summer turnout an option? Would a dry lot be better than pasture?
A:Summer pasture-associated equine asthma typically affects horses during hot, humid weather. It’s commonly seen in subtropical states, like Mississippi and Florida, but can occur in other areas with similar weather conditions. Although the exact triggers for this condition are not fully understood, pollen and fungi are likely culprits.
Regardless of the cause, environmental management is crucial in treating equine asthma. The primary focus is on removing as many triggers as possible. Although horses with barn dust-associated asthma tend to fare better outside, those with pasture-associated equine asthma typically benefit from being kept indoors during the summer—in fact, some may even require a climate-controlled environment. Of course, when horses are kept indoors, minimizing dust from bedding, feed and other sources is essential. Putting a horse with pasture-associated heaves on a dry lot may not be sufficient due to the likelihood of exposure to pollen and other airborne particles from nearby fields, wooded areas and pastures.
During periods of remission, usually during the winter months, horses with pasture-associated equine asthma can be turned out. Individual horses may be affected differently by certain types of grasses at specific times of the year. Ideally, owners will monitor their horses to connect the onset of clinical signs to a specific part of the season, and perhaps the growth/bloom of specific trees/grasses. Once triggers are identified, steps can he taken to reduce exposure to them, such as temporarily removing the horse from the pasture. Relocating horses with asthma to northern states can also be beneficial but this is not an option for most owners.
In addition to managing a horse’s environment, medications like glucocorticoids are often necessary to reduce inflammation affecting the respiratory tract. Glucocorticoids can be administered orally, by injection, or inhalation with a new FDAapproved ciclesonide inhalation spray for severe equine asthma. Bronchodilators may also be used to help relax the smooth muscles surrounding the airways. However, environmental management remains vital. Without reducing a horse’s exposure to triggers, medications may have limited effects, and signs may return when treatment is discontinued.
All in all, by addressing triggers and employing appropriate medical interventions, owners can improve the health and well-being of horses with equine asthma. Jamie Pribyl, DVM
Professional Services Veterinarian Boehringer Ingelheim