By: Dr. Clair Thunes, Ph.D.

Each year in December, equine veterinarians from across the world gather for the American Association of Equine Practitioners annual convention. This year, the meeting was in Denver and, for the third year in a row, EnviroEquine & PET was in attendance sharing what we do with the veterinary community while expanding our knowledge. As is the case every year, there was no lack of information available for those ready and willing to learn. Following a few days packed full of learning, we came away with several key takeaways of important information that we wanted to share.

Did you know that fungi can exist in your horse’s airway and may contribute to airway inflammation in horses with recurrent airway obstruction?

In horses referred to a veterinary hospital for respiratory disease, 55 percent had a positive fungal culture. Horses with fungi in their airway were twice as likely to have inflammatory airway disease (IAD) than those without fungi.

Where do these fungi come from? Most commonly they originate in the horse’s forage and bedding.

Traditionally, soaking hay has been used to improve airway health in horses with IAD. Surprisingly though, soaking hay does not decrease the risk factors of developing IAD from fungal spores in forage. The only way to lower spores from long stem forage is to steam it. Of the types of bedding horses were housed with, straw was found to have the highest number of horses diagnosed with IAD with fungal spores in their tracheal wash samples. Some alternative types of bedding fared even worse than straw.

The take-home from this research is that horses breathing airborne fungal particles are significantly more likely to develop IAD and owners need to pay careful attention to the types of bedding and the quality of the forage they are feeding.

At EnviroEquine & PET, we have a solution to fungal spores in bedding thanks to Aubiose hemp bedding, which is dust-extracted and very low in fungal spores. Additionally, its ability to absorb four times its weight in urine results in further improvements in air quality over other common forms of stable bedding.

Equine influenza (EIV) also impacts respiratory health.

A study of 7,809 equids with acute onset of fever and respiratory signs were tested for EIV and 9.2 percent were found to test positive. Of these positive horses, most were Quarter Horses used in competition aged between 1 and 9 years of age. Also interesting was that the researchers found that more EIV cases originated in the winter and spring months, confirming that a “flu season” exists in horses as it does in people. While significantly more horses that were vaccinated for EIV were found to be negative for the disease versus unvaccinated horses, 61 percent of cases occurred in vaccinated horses.

These findings suggest that horses of certain breeds may be at greater risk of developing EIV. While the EIV vaccine may not be fully effective at preventing EIV in all horses, these results show that vaccination against EIV, especially in young horses travelling for competition in the winter and spring, is still a crucial component of effective equine management.

As we head into the winter competition season, make sure that your performance horses and other in your barn are up-to-date on their vaccinations and protect their airway health by making smart bedding and forage choices.