The value of odors for promoting psychologic wellbeing is well documented in the human medical literature. Results of research suggest that both mood1–3 and behavior4–6 can be influenced by odors. The scents of lavender, chamomile, and sandalwood, for example, reduce anxiety and encourage positive affect,3,7,8 whereas those of peppermint, jasmine, and rosemary have been reported to improve alertness and enhance cognitive performance.9–11
Recently, research attention has been directed toward the potential value of odors for influencing the well-being of animals. The value of olfactory enrichment has been studied in multiple species including cats,12–15 mice,16–19 and pigs.20 In many of those studies, changes were reported in the behavior or physiologic state of animals exposed to various aromas, including herbs, spices, essential oils, and the excrement or body odor of potential prey.
Dogs have also been reported to benefit from exposure to certain odors. Dogs housed in a rescue shelter responded to the introduction of diffused lavender and, to a lesser extent, chamomile, by spending more time displaying behaviors suggestive of relaxation such as increased resting and decreased barking.21 Diffused odor of peppermint and rosemary, in contrast, encouraged greater activity and vocalization, behaviors that were more suggestive of agitation.
The purpose of the present study was to determine the effect of olfactory stimulation with lavender on the behavior of dogs in the confined setting of the automobile. Many dogs are prone to travel-induced excitement, which often arises from the prospect of going for a walk. Typical signs of overexcitement in the car include excessive barking, hyperventilation, and hyperactivity. Not only do those behaviors have implications for the dogs' welfare because they may result in injury, but also they can be a serious distraction to the driver. Traditional treatments for travel-induced excitement have typically relied on counterconditioning or systematic desensitization (eg, taking the dog for a short car journey in the absence of the usual reinforcers), application of antibarking devices,22 and administration of psychopharmacologic drugs23 such as b-adrenoreceptor blockers and benzodiazepines. However, these treatments can be time-consuming, expensive, and associated with unwanted effects such as drowsiness.
The present study investigated the effect of exposure to the ambient odor of lavender, an herb known for relaxant properties, on the behavior of dogs traveling in cars to establish whether this type of olfactory stimulation has merit as an alternative treatment for travel-induced excitement in dogs. It was hypothesized that lavender would have a calming effect on dogs.
NV-VZ9B, Panasonic, Bracknell, Berkshire, UK.
SPSS for Windows, version 13.0, SPSS Inc, Chicago, Ill.
Schoon GAA. The performance of dogs in identifying humans by scent. PhD thesis, Department of Criminalistics and Forensic Science, University of Leiden, Leiden, The Netherlands, 1997.
Ludvigson HW, Rottman R. Effects of ambient odours of lavender and cloves on cognition, memory, affect and mood. Chem Senses 1989;14:525–536.
Moss M, Cook J, Wesnes K, et al. Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. Int J Neurosci 2003;113:15–38.
Baron RA. Environmentally induced positive affect: its impact on self-efficacy, task performance, negotiation, and conflict. J Appl Soc Psychol 1990;20:368–384.
Baron RA, Thomley J. A whiff of reality: positive affect as a potential mediator of the effects of pleasant fragrances on task performance and helping. Environ Behav 1994;26:766–784.
Raudenbush B, Corley N, Eppich W. Enhancing athletic performance through the administration of peppermint odor. J Sport Exerc Psychol 2001;23:156–160.
Roberts A, Williams JMG. The effect of olfactory stimulation on fluency, vividness of imagery and associated mood—a preliminary study. Br J Med Psychol 1992;65:197–199.
Schwartz GE, Whitehorn D, Hernon JC, et al. Subjective and respiratory differences of fragrances: interactions with hedonics (abstr). Psychophysiology 1986;23(4):460.
Diego MA, Jones NA, Field T, et al. Aromatherapy positively affects mood, EEG patterns of alertness, and math computations. Int J Neurosci 1998;96:217–224.
Kovar KA, Gropper B, Ammon HTP. Blood levels of 1,8 cineole and locomotor activity of mice after inhalation and oral administration of rosemary oil. Planta Med 1987;53:315–319.
Powell DM. Preliminary evaluation of environmental enrichment techniques for African lions (Panthera leo). Anim Welf 1995;4:361–370.
Schuett EB, Frase BA. Making scents: using the olfactory senses for lion enrichment. The Shape of Enrichment August 2001;10 (3):1–3.
Wells DL, Egli JM. The influence of olfactory enrichment on the behaviour of black-footed cats, Felis nigripes. Appl Anim Behav Sci 2004;85:107–119.
Buchbauer G, Jirovetz L, Jager W, et al. Aromatherapy: evidence for the sedative effect of the essential oil of lavender after inhalation. Z Naturforsch [C] 1991;46c:1067–1072.
Buchbauer G, Jirovetz L, Jager W, et al. Fragrance compounds and essential oils with sedative effects upon inhalation. J Pharm Sci 1993;82:660–664.
Umezu T. Behavioural effects of plant derived essential oils in the Geller type conflict test in mice. Jpn J Pharmacol 2000;83:150–153.
Umezu T, Sakata A, Hiroyasu I. Ambulation promoting effect of peppermint oil and identification of its active constituents. Pharmacol Biochem Behav 2001;69:383–390.
Bradshaw RH, Marchant JN, Meredith MJ, et al. Effects of lavender straw on stress and travel sickness in pigs. J Altern Complement Med 1998;4:271–275.
Graham L, Wells DL, Hepper PG. The influence of olfactory stimulation on the behaviour of dogs housed in a rescue shelter. Appl Anim Behav Sci 2005;91:143–153.
Wells DL. The effectiveness of a citronella spray collar in reducing certain forms of barking in dogs. Appl Anim Behav Sci 2001;73:299–309.
Ostrower S, Brent L. Olfactory enrichment for captive chimpanzees: responses to different odors. Laboratory Primate Newsletter 2000;36 (1):8–12.
Lehrner J, Marwinski G, Lehr S, et al. Ambient odors of orange and lavender reduce anxiety and improve mood in a dental office. Physiol Behav 2005;86:92–95.
Sakamoto R, Minoura K, Usai A, et al. Effectiveness of aroma on work efficiency: lavender aroma during recesses prevents deterioration of work performance. Chem Senses 2005;30:683–691.