Is aromatherapy good for horses?

August 06, 2018

Maybe you have a favorite scent that helps you relax: something like eucalyptus, or lilac, or jasmine, or cinnamon. Well, according to a recent study, horses do as well — and it’s lavender.

Researchers from the University of Arizona found significant signs of stress reduction in horses after the horses inhaled the scent of lavender. They exposed nine dressage horses to the scent without provoking stress first, in order to determine how the aromatherapy would affect a horse in its natural state (a previous study had shown lavender to help stressed-out horses when the stress was induced by an airhorn). The horses’ ages and breeds varied.

“We wanted to test regular horses that aren’t stressed out by external forces,” said university professor and dressage rider Ann Baldwin. “Some horses and some breeds, it’s just in their nature that they are more stressed. So, we wanted to use horses that were not being scared deliberately to see what effect, if any, the aromatherapy had on them.”

In the study, horses were separated individually into a small paddock while a volunteer held a diffuser containing lavender essential oil near their noses. A monitor tracked the horses’ heart rates and heart rate variability for 21 minutes — seven minutes before lavender exposure, seven minutes during exposure, and seven minutes afterwards.

Interestingly, the horses’ heart rates didn’t change while sniffing, but something else did: heart rate variability. A calculation involved in heart rate variability called “root mean square of the successive differences” (RMSSD) increased, which is tied to the relaxation part of the automatic nervous system.

“We found that when the horses were sniffing lavender, RMSSD significantly increased compared to baseline,” said Baldwin. This change was noted in horse behavior, too — the horses lowered their necks, licked and chewed while smelling the lavender. Such changes weren’t noticed when other scents were used.

The researchers hope this information can be useful to horse caretakers who want to calm their animals without the long-lasting effects of traditional tranquilizers. Lavender could be easily used in a few practical situations that make some horses nervous, like when they’re being shod or loaded into trailers.

“You don’t need a diffuser, really,” said Baldwin. “Just put a few drops of lavender essential oil on your hand and let your horses sniff.”