Sniff of lavender can return horse to equine equanimity

LAVENDER is the secret to keeping a horse calm, a study by scientists have found.

Horses are regularly put through stressful events such as being moved on trailers, bathing, clipping, vet visits, hoof trims, bridling and saddling.

But now the University of Arizona has discovered that a quick sniff of lavender can lower the heart rate and keep the animal calm.

The study, which was published in the Journal of Equine Veterinary Science, found significant signs of stress reduction in horses that inhaled lavender from a diffuser.

Ann Baldwin, professor of physiology and psychology, said: “Some horses don’t like to be shod. So, when the farrier starts banging around with their hooves, it would be good for that. You don’t need a diffuser, really. Just put a few drops of lavender essential oil on your hand and let your horse sniff.”

For the study, horses were startled by an air horn and then provided with humidified lavender air. The horses’ heart rates increased in response to the air horn but returned to normal more quickly in those that inhaled lavender. In a second study, Prof Baldwin enlisted nine dressage horses of varying breeds and ages.

Each horse was led to a small paddock and held by a volunteer while a diffuser containing lavender essential oil was held near the horse’s nose.

A monitor tracked heart rates and heart rate variability for 21 minutes in total – seven minutes before the diffuser’s introduction, seven minutes with the diffuser in close proximity and seven minutes after it was removed.

“The heart rate did not change; what changed is what’s called the parasympathetic component of heart rate variability,” she said.

“One of the parameters of heart rate variability is the root mean square of the successive differences, which is the relaxation part of the autonomic nervous system. If it goes up, that indicates the horse is relaxed. We found that when the horses were sniffing the lavender, it significantly increased compared to baseline.”

The data were supported by the horses’ observed behaviour, which often included relaxation signals such as neck lowering, licking and chewing.