Transport of horses to and from clinics and competitions adds a layer of stress that has the potential to not only interfere with performance, but also to suppress a horse’s immune system. Researchers decided to look at possible beneficial effects of using lavender aromatherapy to minimize cortisol responses in trailered horses [Heitman, K.; Rabquer, B.; Heitman, E.; Streu, C.; and Anderson, P. The Use of Lavender Aromatherapy to Relieve Stress in Trailered Horses. Journal of Equine Veterinary Science 2018].
A mixture of 20% lavender oil with 80% distilled water was diffused through a vaporizer in the trailer for the duration of the horses’ trailer ride. Four groups of two horses were driven for 5½ miles for 15 minutes. Eight control horses were transported with the vaporizer only diffusing distilled water into the trailer’s air.
Blood samples taken prior to the trailering, immediately after, and 50 minutes later were checked for cortisol concentrations. Heart rates were taken at these same time intervals. The study was repeated four weeks later, but the initial four horses that served as controls were now the ones subjected to the lavender aromatherapy and the ones previously given aromatherapy now served as controls.
The study concluded: “Overall, our results show that cortisol levels were suppressed in stressed horses that received lavender aromatherapy.” Heart rates were not significantly changed with aromatherapy.
Lavender aromatherapy has been shown to reduce stress responses in a variety of other species, such as pigs, sheep and humans.