WEST LAFAYETTE — What comes to mind when you think about asthma? For Dr. Laurent Couetil, horses are top of mind.
Why horses?
"There are really only two species of animals that also have asthma," Dr. Couetil shared. "Besides horses, it's cats."
Dr. Couetil is a researcher at Purdue University in the College of Veterinary Medicine.
His focus is to learn more about asthma in horses — what causes it and how to treat it.
"Hay is actually the main type of feed they are allergic to," Dr. Couetil shared. "The dust in the hay."
When visiting the Asthma Herd (as the group of asthmatic horses at the university is affectionately called), I noticed a sign that said "no hay" outside their pasture.
Just like humans, asthmatic horses don't deal well with dust.
To measure the dust that horses are encountering, Dr. Couetil showed me a halter equipped with technology.
The halter is designed to be worn through everyday activities, so researchers can learn when and where horses are encountering a lot of dust.
A fan sucks in air (including any dust) to be measured in real time. The halter also has a camera to see where horses are when dust levels are high.
Why is this important?
"We can tell if the bedding, for example, is a cause of them being exposed to a lot of dust, or is it their feed, or the hay," he concluded.
Once dust is inhaled, it can trigger the horse's asthma.
Dr. Couetil has worked to develop a mask for horses to wear that can prevent them from inhaling dust.
A lot of dust comes from the food horses eat, which is when the mask will be worn.
"Horses, they are what we call obligatory nose breathers," Dr. Couetil shared. "They have to breathe through their nose. They cannot breathe through their mouth like us."
"They can be exposed when they eat their hay, but then there was an opportunity to put something on their nose that would filter the air they breathe," he said.
Dr. Couetil shared that he worked with an occupational health team to create the horse mask. He hopes that one day horse owners will be able to utilize masks like this when feeding their asthmatic horses.
Why is asthma problematic in horses? Dr. Couetil shared that all horses can struggle with breathing, but breathing problems can be critical for horses that compete.
"It could be more bothering for the athletic horses, because they need all their lung capacity," Dr. Couetil said.
I got to witness how Dr. Couetil's team works with athletic horses. Nestled in the middle of other veterinary buildings on campus was a building labeled "Equine Treadmill."
Here, horses are worked out on a larger than life treadmill. Horses can walk, trot and canter. The treadmill can also go on a slight incline. Horses are hooked up to devices that measure their heart rate.
Dr. Couetil explained to me during the treadmill demonstration that many problems cannot be diagnosed in racehorses until the horse is working, which is why they get them running on the treadmill to raise their heart rate.
Back on the Veterinary Medicine Farm, I also got to see Dr. Couetil put a nebulizer on a horse. It allows the horse to breathe in medicine, similar to the way humans do.
A big part of Dr. Couetil's findings have to deal with horses' diets.
According to Dr. Couetil, horses get natural anti-inflammatories from eating grass. When horses' diets have more hay than grass, asthma can be triggered.
Dr. Couetil thinks he has a solution for horses that don't have access to grass: omega-3s.
The team added fish oil (full of omega-3s) to the horses' diets.
"We've done several studies now to show that supplementing horses that aren't kept in those conditions, where they don't have access to grass, really benefit from having that added to their feed," Dr. Couetil concluded.
He is proud of this result, and what it means for horse owners.
"The supplement really helped decrease the irritation, the inflammation in their lungs," he continued. "When we looked at their performance, they did better. So essentially, we were able to show that they can go back to their full potential, essentially, if they can recover from that irritation in their lungs."
I asked if there were any connections between his findings with asthma in horses to asthma in humans.
"As we publish this," Dr. Couetil said of his findings with the fish oil supplement, "We can really have more convincing evidence that we should revisit in people, and maybe have a different type of study designed to make sure we can detect the effect if it's there."
I also reached out to Dr. Kirsten Kloepfer, Medical Doctor and Allergist at Riley Hospital for Children, to talk about the findings in horses. She mentioned that there have already been lots of meetings where veterinarians and Medical Doctors collaborate.
"They'll present their research, and it's great because then we can sometimes get ideas of things they've been able to do," Dr. Kloepfer shared. "And potentially translate it over to humans."
Dr. Kloepfer said that asthma research has come a long way for humans, too.
"With asthma treatment, we've seen, we've made some really significant strides in the last five, 10 years," Dr. Kloepfer said.
Dr. Kloepfer said treatments for asthma stemming from allergies has made the biggest progress recently.
"We have patients now who have never been able to swim because they can't hold their breath long enough to go underwater, could never ride a bicycle, really couldn't participate in PE or recess during school, and so now they can live what we consider to be like a normal life," Kloepfer shared.
Research is ongoing in humans, especially in cases that are not related to allergic asthma.
"If we could prevent asthma, that'd be life changing for a lot of patients," Dr. Kloepfer said.
Both Dr. Couetil and Dr. Kloepfer will continue their research to make sure their patients — the horses and the humans — can one day breathe easier.
