In a recent experiment by Isabelle Chea, a then-undergraduate honors student at the UA, and Ann Baldwin, UA professor of physiology and psychology, found that sniffing lavender calmed horses. However, the calming affect only lasted while they were sniffing the vapor.
This is a good thing because the traditional method of calming a nervous horse is to use tranquilizers which remain in the horse after it is needed. However, sniffing the lavender can be used only when needed with no side or prolonged affects.
Professor Baldwin plans to try other scents and doses to see if they calm horses as well. I would love to see experiments on dogs and cats using various types of aromatherapy to calm them, especially for veterinarian visits.