In this study, twenty-eight Welsh horse fillies were divided into two groups: horses treated with a roll-on with 2 mL of vegetable oil (control) and horses treated with 2 mL of 10% lavender essential oil in vegetable oil. Horses were then subjected to a series of stress tests. Heart rates and stress behavioral indicators were monitored during the 30 min of the stress tests.
Results show that stress indicators such as heart rate, alert postures and defecations are lower in lavender oil-treated horses. Lavender essential oil also modified salivary cortisol. Pharmacokinetics of linalool in plasma displayed a peak 20 min after lavender essential oil application, thus confirming the effect of lavender oil. Overall, the findings demonstrate that lavender essential oil reduces the response to stress of horses placed in stressful situations.