Psychiatric service dogs affect cortisol in military veterans with PTSD

By Kerri E. Rodriguez

Up to 23% of post-9/11 military veterans in the United States have PTSD (Fulton et al., 2015), and an average of 20 veterans commit suicide each day. Many veterans are turning to specially trained PTSD service dogs to help alleviate the daily challenges that they face from the trauma of combat and war. Our latest study (Rodriguez et al., 2018) suggests that having a PTSD service dog may not only be psychologically beneficial for military veterans, but may also affect the body’s stress response system as well.

PTSD Service Dogs

A service dog is a type of assistance animal that is trained to do work or perform tasks to help a handler with a physical disability or mental condition (Americans With Disabilities Act of 1990). While some service dogs may turn on and off lights or alert to low blood sugar, psychiatric service dogs can be trained to perform tasks relevant to PTSD. For example, a PTSD service dog may learn to wake their handler up from a nightmare or distract them from anxiety experienced during a flashback.


Retired Army veteran Carlos Cruz and Hanna, his PTSD service dog from K9s For Warriors Credit:

Research from both our research group (O’Haire & Rodriguez, 2018) and others (Yarborough et al. 2017; Klopp, Hunter & Kreuz, 2017; Bergen-Cico et al., 2018) has found that psychiatric service dogs can have positive effects on mental health, social functioning, and quality of life among military veterans with PTSD. However, these findings are self-reported; while veterans’ perceived stress levels may be lower when their service dog is present, we can’t account for the possibility that these reports may be inflated, or biased.

In our most recent study (Rodriguez et al., 2018), we sought to test the hypothesis that a PTSD service dog would have an effect on the stress hormone cortisol – a physiological biomarker that can’t be inflated or biased.

This research is important, as without empirical studies that establish the therapeutic efficacy of PTSD service dogs, this popular practice used by thousands of military veterans across the US will continue to be empirically unsupported. The U.S. Department of Veterans Affairs (VA) has stated that they will not fund psychiatric service dogs as a treatment for PTSD as there remains a lack of researchon their psychological and physiological effects. While we have preliminary qualitative and quantitative evidence that service dogs may be helping veterans with PTSD in clinically meaningful ways (Krause-Parello, Sarni & Padden, 2016) the field needs rigorous, replicable science behind these reports.

PTSD and Cortisol

Cortisol is famously referred to as “the stress hormone” – this is because cortisol is a main product of the brain’s stress response system. Every morning when you wake up, you experience a 50-75% increase in the levels of circulating cortisol in your bloodstream (Pressier et al., 1997). In healthy adults, the magnitude of this cortisol awakening response, or the CAR, is continuously linked to both higher acute and chronic stress (Chida & Steptoe, 2009).

However, research suggests that individuals with PTSD have abnormally low production of cortisol in the mornings (Wessa et al., 2006). Because of this deficiency in cortisol production, a higher CAR may not actually mean more stress in this population. In fact, highermorning cortisol may indicate that an individual with PTSD is exhibiting a cortisol profile closer to that of healthy adults without PTSD symptoms.

PTSD Service Dogs and the CAR

Our recent research (Rodriguez et al., 2018), published in Psychoneuroendocrinology, aimed to compare the cortisol awakening response among a group of military veterans with PTSD who either had a service dog or were on the waitlist to receive one.

To conduct the study, we teamed up with national service dog provider K9s For Warriors, one of the largest providers of PTSD service dogs in the country. We had 73 veterans participate in the study, including 45 who had already been placed with a service dog and 28 on the waitlist.

To measure the CAR, veterans simply had to fill up two vials: one immediately after waking up, and the second about 30 minutes later. By using user-friendly instructions, color-coded vials, and text messaging to remind participants when to collect their samples, we collected hundreds of samples from veterans across


Instructions given to participants on how to collect saliva samples. Credit: Kerri Rodriguez

the country. We also asked veterans to fill out an online survey, which asked about their demographics, sleep, and psychosocial health.

What Did We Find?

 We found that having a service dog was indeed related to having higher cortisol production in the morning. Specifically, after controlling for several demographic and medical characteristics that may influence cortisol, we found that having a service dog was significantly associated with a larger CAR.


A graphic display of the cortisol awakening response (CAR) and the area under the curve with respect to increase (AUCi) by group. Note: Covariate-adjusted CAR and AUCi are displayed as least square means (LSM) from mixed model output, controlling for age, sex, use of a mobility aid, body mass index (BMI), physical health (VR-12 PCS), alcohol use, sleep disturbance, cortisol-influencing medication, waking cortisol value, and wake time.

Although we don’t know if this magnitude difference in the CAR is clinically relevant for PTSD, a higher CAR among those with a service dog may suggest better health and wellbeing in this population.

We also found that those with a service dog reported significantly less PTSD severity as well as less anger, anxiety, sleep disturbance, and alcohol abuse symptoms than those on the waitlist. These findings mirror that of similar studies that have found evidence for the therapeutic efficacy of service dogs for military veterans with PTSD (Krause-Parello, Sarni & Padden, 2016).

While this finding is important, it should be interpreted cautiously. As this study was cross-sectional, we can’t determine that the findings are causational. That is, we still don’t know if a PTSD service dog directly affects cortisol production in this population. We also don’t have a complete grasp of the mechanism for how dogs can influence the body’s stress response system, nor do we know how individual differences in either veterans or service dogs might be important for understanding our findings.

The next step to answer these questions is already underway. Our research group is currently conductinga large-scale National Institutes of Health (NIH) funded clinical trialin which we will be teaming up with K9s For Warriorsto follow veterans with and without service dogs over an extended period of time. This will allow us to be able to look at within-individual cortisol levels both before and after getting a service dog to see how these changes may occur over time on a much larger scale.


  1. Fulton, J.J., et al., The prevalence of posttraumatic stress disorder in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans: a meta-analysis.Journal of anxiety disorders, 2015. 31: p. 98-107.
  2. Rodriguez, K.E., et al., The effect of a service dog on salivary cortisol awakening response in a military population with posttraumatic stress disorder (PTSD).Psychoneuroendocrinology, 2018. 98: p. 202-210.
  3. Americans With Disabilities Act of 1990, Pub. L. No. 101-336, 104 Stat. 328. 1990.
  4. O’Haire, M.E. and K.E. Rodriguez, Preliminary efficacy of service dogs as a complementary treatment for posttraumatic stress disorder in military members and veterans.Journal of consulting and clinical psychology, 2018. 86(2): p. 179-188.
  5. Yarborough, B.J.H., et al., An Observational Study of Service Dogs for Veterans With Posttraumatic Stress Disorder.Psychiatric Services, 2017. 68(7): p. 730-734.
  6. Kloep, M.L., R.H. Hunter, and S.J. Kertz, Examining the Effects of a Novel Training Program and Use of Psychiatric Service Dogs for Military-Related PTSD and Associated Symptoms.Am J Orthopsychiatry, 2017. 87(4): p. 425.
  7. Bergen-Cico, D., et al., Dog Ownership and Training Reduces Post-Traumatic Stress Symptoms and Increases Self-Compassion Among Veterans: Results of a Longitudinal Control Study.The Journal of Alternative and Complementary Medicine, 2018. 24(12): p. 1166-1175.
  8. Krause-Parello, C.A., S. Sarni, and E. Padden, Military veterans and canine assistance for post-traumatic stress disorder: A narrative review of the literature.Nurse Education Today, 2016. 47: p. 43-50.
  9. Pruessner, J., et al., Free cortisol levels after awakening: a reliable biological marker for the assessment of adrenocortical activity.Life sciences, 1997. 61(26): p. 2539-2549.
  10. Chida, Y. and A. Steptoe, Cortisol awakening response and psychosocial factors: A systematic review and meta-analysis.Biological Psychology, 2009. 80(3): p. 265-278.
  11. Wessa, M., et al., Altered cortisol awakening response in posttraumatic stress disorder.Psychoneuroendocrinology, 2006. 31(2): p. 209-215.

Citation:Rodriguez, K. E., Bryce, C. I., Granger, D. A., & O’Haire, M. E. (2018). The effect of a service dog on salivary cortisol awakening response in a military population with posttraumatic stress disorder (PTSD). Psychoneuroendocrinology, 98, 202-210.

About the Author: Kerri Rodriguez is a 4thyear Ph.D. student of Dr. Marguerite O’Haire in the Center for the Human-Animal Bond at Purdue University. Her research focuses on studying the psychological and physiological effects of service dogs both within military veterans with PTSD as well as individuals with physical disabilities. You can reach her via emailor linkedin. To learn more about the Center for the Human-Animal Bond’s research, visit their website at

The ISAZ Student Blog is posted quarterly  and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply. 


Happy New Year and Introduction of new members of the ISAZ Student Committee

We wish all our readers a very happy new year! As start into the new year we would like to introduce our new Student Committee members. As a new team we are very motivated for upcoming projects with the aim to promote networking of young researchers interested in the field of Anthrozoology. Following you´ll find short Bios of our Committee to get a quick insight into the team.

Molly Crossman


Hi everyone—my name is Molly. I am the chair of the ISAZ Student Committee and I’m excited to be back for the second year of my two-year term as ISAZ Student Board Member. I am currently a sixth-year doctoral student in clinical psychology at Yale University and a clinical psychology intern at McLean Hospital/Harvard Medical School. I also currently co-direct the Yale Innovative Interactions Lab, which is directed by Dr. Laurie Santos. Our work in the lab is focused on establishing human-animal interactions as an efficient strategy for improving human mental health, as well as understanding some of the processes through which these interactions might improve human mental health.

Please don’t hesitate to be in touch with the committee if you have any questions, comments, or suggestions! Don’t forget to join the ISAZ Student Facebook Group and let me know if you would like to be added to the student Google group. You can reach me at We look forward to seeing folks in Orlando this July!

Sara Owczarczak-Garstecka


I’m Sara and I’m studying for a PhD entitled Dog Bites: Perceptions and Prevention at the University of Liverpool, UK, supervised by a team led by Dr Carri Westgarth. During my Bachelor’s degree in Anthropology at the University College London, I became interested in human-animal interactions and developed a passion for interdisciplinary research. Later, I began volunteering for a dog shelter and a London city farm and started learning about animal behaviour and welfare and how to apply it in practice. This led me to a Masters degree in Clinical Animal Behaviour at the University of Lincoln and working as a clinical animal behaviourist.

I enjoy my PhD because it is really applied— I often work with people who work with or around dogs and, alongside my supervisors, advise on bite prevention. I also enjoy learning about human behavior change and how it can be harnessed to improve safety in human-animal interactions.

I attended my first ISAZ conference in Barcelona in 2016 and then in Sydney 2018. Meeting conference attendees and immersing myself in ISAZ talks is a huge motivation boost and an inspiration for further research. I’m really happy to be a part of the Student Committee this year and to assist in issuing the ISAZ Newsletter.

Lisa Emmett


Hi my name is Lisa Emmett and I live in Vienna, Austria with a Bobtail (Old English Sheepdog) called Luna. I did my Bachelors degree in psychology and my Masters in clinical psychology at Sigmund Freud University in Vienna. Subsequently, I completed postgraduate training to become a health and clinical psychologist. In that role, I gained practical experiences in several health facilities and psychiatric departments. I am working on my PhD in psychotherapy science and a training to become a CBT therapist. My dog Luna and I are also in training to become a therapy dog team, because I would love to have her as a co-therapist in my treatments.

With the help of Luna and my supervisor, Dr. Birgit U., I became fascinated by the field of Anthrozoology. My PhD thesis focuses on the development of a questionnaire measuring the suitability of dog owners. This past July it was my first time at ISAZ in Sydney and I am still very grateful that I had the opportunity of meeting all these impressive scientists and practitioners in the field. I am very excited to be on the ISAZ Student Committee and to be co-editing the Student Blog this year.

The ISAZ Student Blog is posted quarterly and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply.

How Does Contact with Wild Dolphins Impact Our Wellbeing and Connection with Nature?

This post comes to us from Rachel Yerbury, winner of the Student Poster Award at the 2018 ISAZ Conference in Sydney, Australia. Thanks to Rachel for sharing her award-winning work with Becoming an Anthrozoologist and our readers.


By Rachel Yerbury

Interactions with non-human animals have been widely studied and shown to have positive impacts on human wellbeing  (Myers & Saunders, 2002; Verbeek & de Waal, 2002; Vining, 2003). Interactions with animals can also nurture people’s connections with nature (Myers & Saunders, 2002; Verbeek & de Waal, 2002; Vining, 2003). Finally, contact with animals may help humans feel emotionally connected to other beings and help overcome feelings of isolation (Kellert, 1996).

In particular, cetaceans (a particular type of marine mammal), including dolphins, have a long history of interaction and attachment with humans (Neil, 2002; Orams, 1997b). Humans commonly seek out encounters with dolphins through leisure, including through tourism (Yerbury & Boyd, 2018). These human-dolphin interactions may elevate positive emotions (Birtles, Valentine, Curnock, Arnold, & Dunstan, 2002; Cloke & Perkins, 2005; Curtin, 2006; DeMares, 2000; Jarvis, 2000; Milstein, 2008), reduce anxiety (Webb & Drummond, 2001) improve nature relatedness (Besio, Johnston, & Longhurst, 2008; Wiener, 2013) and encourage conservation behaviours (e.g. Kortenkamp & Moore, 2001; Mayes, Dyer, & Richins, 2004; Orams, 1997a; Zeppel, 2008; Zeppel & Muloin, 2008).  However, a key question about human-dolphin interactions remains, and that is how and why do interactions with dolphins affect human wellbeing?

The Study

In a recent study, my collaborator, Dr. Bill Boyd, and I set out to explore the phenomena of human-dolphin interactions and to see how such interactions contribute to human wellbeing. We conducted semi-structured interviews with 8 people (5 females and 3 males). These participants had all had contact with wild dolphins in varying degrees and in varying situations. The  eight interview narratives were transcribed into Nvivo11 for Mac and we used Interpretative Phenomenological Analysis (IPA) to identify concept clusters and themes to help make sense of the human experience of the phenomena.

What We Found

The narratives and themes diverged individually, but the dominant theme was Relationship and Connectedness. This main theme included subthemes such as; connection with non-human animals in general, ascribing human characteristics to animals, connection with nature in general, experiencing closeness and proximity to the dolphin thorough eye contact or physical touch and the desire to protect or help dolphins.

Participants expressed strong emotional connections to the dolphins, and described these connections as being relevant to their senses of wellbeing. Participants contextualized these experiences through a lifelong and ongoing connection with nature and animals; in many cases this connection spurred a sense of responsibility and action towards nature and animals. These results were published in a recent edition of Anthrozoös (Yerbury & Boyd, 2018a).

speech bubbles

Some of the responses from the participants are shown above.


Above is an Nvivo word cloud which shows the commonly used words in the narratives.

What These Findings Say About Human-Dolphin Interactions

These findings suggest that people can develop strong and personally important connections with wild animals such as dolphins. (Chawla, 1998; Milligan & Bingley, 2007). As relationships and emotional connection are two important factors for human wellbeing (Seligman, 2011), the results suggest that wild animal contact may fulfill some of the human needs for connection and relationships and in turn contribute to wellbeing. While this study considered the interaction from the human point of view, it is also important to look at the effects of the interactions on wild dolphins, to ensure the rights and wellbeing of the dolphins are also respected. For more on this, readers are directed to a chapter we have written that addresses this topic in Wild Animals and Leisure: Rights and Wellbeing (Yerbury & Boyd, 2018b). While it is not appropriate for humans to interfere with wild dolphins, the narratives in this study describe situations where wild dolphins interacted on their own terms with, or were being helped by humans. Therefore, a reciprocal relationship was indicated: if people see themselves as being connected to the natural world and to its animals, they will be more likely to maintain the connection, which includes both experiencing higher wellbeing and also working to protect the natural world and its components.


Besio, K., Johnston, L., & Longhurst, R. (2008). Sexy beasts and devoted mums: narrating nature through dolphin tourism. Environment and Planning A, 40(5), 1219-1234. doi:10.1068/a38424

Birtles, A., Valentine, P., Curnock, M., Arnold, P., & Dunstan, A. (2002). Incorporating visitor experiences into ecologically sustainable dwarf minke whale tourism in the northern Great Barrier Reef (CRC Reef Research Centre Technical report 42). Retrieved from

Chawla, L. (1998). Significant Life Experiences Revisited: A Review of Research on Sources of Environmental Sensitivity. The Journal of Environmental Education, 29(3), 11-21. doi:10.1080/00958969809599114

Cloke, P., & Perkins, H. C. (2005). Cetacean performance and tourism in Kaikoura, New Zealand. Environment and Planning D: Society and Space, 23(6), 903-924. doi:10.1068/d57j

Curtin, S. (2006). Swimming with dolphins: a phenomenological exploration of tourist recollections. International Journal of Tourism Research, 8(4), 301-315. doi:10.1002/jtr.577

DeMares, R. (2000). Human peak experience triggered by encounters with cetaceans. Anthrozoos: A Multidisciplinary Journal of The Interactions of People & Animals, 13(2), 89-103.

Jarvis, C. H. (2000). If Descartes Swam with Dolphins: The framing and consumption of marine animals in Contemporary Australian Tourism. (Doctor of Philosophy), University of Melbourne,

Kortenkamp, K. V., & Moore, C. F. (2001). Ecocentrism and Anthropocentrism: Moral Reasoning About Ecological Commons Dilemmas. Journal of Environmental Psychology, 21(3), 261-272. doi:10.1006/jevp.2001.0205

Mayes, G., Dyer, P., & Richins, H. (2004). Dolphin-human Interaction: Pro-environmental Attitudes, Beliefs and Intended Behaviours and Actions of Participants in Interpretation Programs: A Pilot Study. Annals of Leisure Research, 7(1), 34-53. doi:10.1080/11745398.2004.10600938

Milligan, C., & Bingley, A. (2007). Restorative places or scary spaces? The impact of woodland on the mental well-being of young adults. Health Place, 13(4), 799-811. doi:10.1016/j.healthplace.2007.01.005

Milstein, T. (2008). When Whales “Speak for Themselves”: Communication as a Mediating force in Wildlife Tourism. Environmental Communication, 2(2), 173-192. doi:10.1080/17524030802141745

Myers, O. E., & Saunders, C. D. (2002). Animals as links toward developing caring relationships with the natural world. In P. H. Kahn & S. Kellert (Eds.), Children and Nature (pp. 153-179). Cambridge, Massachusetts: MIT press.

Neil, D. T. (2002). Cooperative fishing interactions between Aboriginal Australians and dolphins in eastern Australia. . Anthrozoos: A Multidisciplinary Journal of The Interactions of People & Animals, 15(1), 3-18.

Orams, M. B. (1997a). The Effectiveness of environmental education: Can we turn tourists into ‘Greenies’? Progress in Tourism and hospitality research., 3, 295-306.

Orams, M. B. (1997b). Historical accounts of human- dolphin interaction and recent developments in wild dolphin based tourism in Australasia. Tourism Management, 18(5), 317-326.

Seligman, M. E. (2011). Flourish: A visionary new understanding of happiness and well-being New York: Free Press.

Verbeek, P., & de Waal, F. B. (2002). The Primate realtionship with nature: Biophilia as a general pattern. In P. H. Kahn & S. Kellert (Eds.), Children and Nature (pp. 1-26). Cambridge, Massachesetts.: MIT Press.

Vining, J. (2003). The connection to other animals and caring for nature. Human Ecology Review, 10(2), 87-99.

Webb, N. L., & Drummond, P. D. (2001). The effect of swimming with dolphins on human well-being and anxiety. Anthrozoos: A Multidisciplinary Journal of The Interactions of People & Animals, 14(2), 81-85.

Wiener, C. (2013). Friendly or dangerous waters? Understanding dolphin swim tourism encounters. Annals of Leisure Research, 16(1), 55-71. doi:10.1080/11745398.2013.768155

Wilson, E. O. (1984). Biophilia, the human bond with other species. Cambridge, MA: Harvard University press.

Yerbury, R.M., & Boyd, W.E (2018a). Human–Dolphin Interactions: Relationships, Connections, and the Reinforcement of an Ongoing Nature Relationship. Anthrozoos, 31(4)

Yerbury, R. M., & Boyd, W. E. (2018b). Wild Dolphins, nature and leisure: Whose wellbeing? In N. Carr & J. Young (Eds.), Wild Animals and Leisure: Rights and Wellbeing (pp. 149-164). New York: Routledge.

Zeppel, H. (2008). Education and conservation benefits of marine wildlife tours: Developing free-choice learning experiences. The Journal of Environmental Education, 39(3), 3-18.

Zeppel, H., & Muloin, S. (2008). Conservation Benefits of Interpretation on Marine Wildlife Tours. Human Dimensions of Wildlife, 13(4), 280-294. doi:10.1080/10871200802187105

About the Author: Rachel Yerbury is a PhD student at Southern Cross University, who is interested in the intersection between nature and wellbeing. As a counseling psychologist for almost 20 years, Rachel understands that an individual’s wellbeing is made up of many factors, in particular their environment and the interactions and relationships that make up their lives, including interactions with animals. Rachel believes that dolphins in particular are a special part of nature, and can have a positive impact on people who interact with them. Rachel also maintains the importance of respect and care of nature and animals and much of her research interest considers these complex ethical and moral questions.  Rachel lives in Wollongong, NSW, Australia with her beloved husband and two beautiful young adult daughters.

The ISAZ Student Blog is posted quarterly  and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply.

How Does Temporary Fostering Affect the Welfare of Shelter Dogs?

By Lisa Gunter


Photo Credit: Charlie Leight, Arizona State University, used with permission

The interconnected lives of a dog and its owner are often mutually satisfying (Beck & Katcher, 1996). Yet, canine-human relationships are complicated; and dogs, whether due to issues facing their owners or the dogs’ own health and behavior challenges, may unfortunately wind up at the animal shelter (Protopopova & Gunter, 2017). It is estimated that over five million dogs enter one of 7,000 animal shelters each year in the United States (Woodruff & Smith, 2017).

Life at the Animal Shelter

While the number of dogs arriving at animal shelters is declining, as well as those that are ultimately euthanized (Rowan & Kartal, 2018), lengths of stay in the shelter are likely increasing as dogs await adoption (Protopopova, 2016). As such, shelters are becoming less like temporary ports in the storm for homeless pets and more akin to long-term orphanages (Barrett & Greene, 2015).


Susan & Jenna during their sleepover with Barret, at Best Friends Animal Sanctuary

Dogs experience a variety of potential stressors when they arrive and during their stay at the animal shelter, including disruptive sounds, restriction of movement, and loss of social attachments (Taylor & Mills, 2007). However, welfare interventions carried out at shelters show that spending time with humans reduces canine stress. Regardless of activity, be it petting, playing, or simply being present in the same room, human interaction can improve the welfare of shelter dogs when compared to remaining in or being removed from the kennel but without a person present (Shiverdecker, Schiml, & Hennessy, 2013). While the benefits of these interventions, such as reductions in cortisol (a hormone involved in the body’s stress response system), do not necessarily persist when dogs return to their kennels, researchers have speculated that longer periods of interaction with people would likely have increased and longer-lasting benefits (Coppola, Grandin, & Enns, 2006).

The Study

Temporarily leaving the shelter is a simple yet promising way to provide increased interaction with people and improve the welfare of dogs awaiting adoption. To evaluate the effectiveness of this approach, Erica Feuerbacher from Virginia Tech University and I first traveled to Best Friends Animal Sanctuary in Utah. The Sanctuary has a sleepover program where dogs leave the shelter for a night with a volunteer, stay at the volunteer’s home, and come back the next morning. To measure stress, urine was collected for the analysis of cortisol and we compared these levels before, during, and after sleepovers. When we expanded our study and the length of the sleepover to two nights, we worked with shelters in Arizona, Montana, Georgia, and Texas.


Harry, a sleepover dog from the SPCA of Texas

What did we find? Just one or two nights out of the shelter significantly reduced the cortisol levels of dogs, although the magnitude of the effect varied across shelters. Dogs’ in-shelter values after sleepover were not significantly lower (or higher) than their initial in-shelter cortisol values, thus the benefits of the sleepover were impactful but short-lived. Additionally, we found that dogs’ longest periods of rest occurred during the sleepovers, and that resting bouts upon return to the shelter were still longer than before the sleepover. Thus, our impression is that these sleepovers function much like weekends to the workweek. They don’t eliminate shelter dogs’ stress but give them an opportunity to rest and recharge.

Furthermore, we were able to detect differences between shelters when comparing their average in-shelter cortisol values. Considering the diversity of shelters in our study, it is certainly possible that as yet unstudied factors, such as dog density, kennel conditions, husbandry, and/or enrichment programs could contribute to the overall welfare of shelter dogs and should be explored further.

Future Directions

In recent years a number of research groups have investigated the kinds of interventions at the shelter that can improve the welfare of the dogs that live in them (Coppola et al., 2006; Menor-Campos, Molleda-Carbonell, & López-Rodríguez, 2011; Shiverdecker et al., 2013). These kinds of out-of-kennel interactions may provide temporary relief for dogs in shelters, but it is also possible that changes in shelter design or daily procedures may  provide benefits in stress reduction.


Beck, A. M., & Katcher, A. H. (1996). Between pets and people: The importance of animal companionship. Purdue University Press.

Protopopova, A., & Gunter, L. M. (2017). Adoption and relinquishment interventions at the animal shelter: A review. Animal Welfare, 26(1), 35-48.

Woodruff, K. A., & Smith, D. R. (2017). An estimate of the number of dogs in US shelters. Available at: Presentation_NAVC_2017.pdf.

Rowan, A., & Kartal, T. (2018). Dog population & dog sheltering trends in the United States of America. Animals8(5).

Protopopova, A. (2016). Effects of sheltering on physiology, immune function, behavior, and the welfare of dogs. Physiology & Behavior159, 95-103.

Barrett, K., & Greene, R. (2015, October). Do animal shelters serve people or pups? Available at: Accessed Feb 12, 2017.

Taylor, K. D., & Mills, D. S. (2007). The effect of the kennel environment on canine welfare: A critical review of experimental studies. Animal Welfare, 16(4), 435.

Shiverdecker, M. D., Schiml, P. A., & Hennessy, M. B. (2013). Human interaction moderates plasma cortisol and behavioral responses of dogs to shelter housing. Physiology & Behavior, 109, 75-79.

Coppola, C. L., Grandin, T., & Enns, R. M. (2006). Human interaction and cortisol: Can human contact reduce stress for shelter dogs? Physiology & Behavior, 87(3), 537-541.

Menor-Campos, D. J., Molleda-Carbonell, J. M., & López-Rodríguez, R. (2011). Effects of exercise and human contact on animal welfare in a dog shelter. The Veterinary Record, 169(15), 388-388.

About the Author: Lisa Gunter, PhD, MA, CPDT-KA is the Maddie’s Research Fellow at Arizona State University in the Department of Psychology and conducts her research in the Canine Science Collaboratory with Clive Wynne. Prior to pursuing her doctorate at Arizona State University from which she graduated in May 2018, Lisa worked for nearly a decade with dogs, both those living in animal shelters and with their owners. The goal of Lisa’s research is to better the lives of shelter dogs. To this aim, she has investigated the perceptional influence of breed labels, what breeds and breed mixes are present in animal shelters, post-adoption interventions focused on owner retention, temporary fostering of dogs awaiting adoption, and identifying behavioral indicators of welfare for kenneled dogs. She has published her research in scientific journals and presented her findings at numerous conferences.

The ISAZ Student Blog is posted quarterly  and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply.


When Stress Travels Down the Leash

By Haley J. Silas


Working in a busy canine therapy program at the University of British Columbia (UBC) has taught me a lot about how dogs can positively impact the well-being of humans. The studies run in UBC’s Building Academic Retention through K9’s (B.A.R.K.) program have shown significant reductions in students’ homesickness (Binfet & Passmore, 2016) and stress levels (Binfet, 2017) and increases in their affinity to campus – how much they feel a part of the campus community (Binfet et al., 2016). With upwards of 60 dogs and handlers working in the various programs offered by B.A.R.K., I’ve also seen how human well-being can impact canine behavior.

Emotional Contagion in Action. Are dogs susceptible to it?

Emotional contagion, a phenomenon when the emotional state of one individual passes to others in the same shared environment (Huber et al., 2017), has been identified in human-to-human interactions. It has been studied in interactions between spouses (Lavee & Ben-Ari, 2007), in employees and customers (Albrecht & Weyerer, 2012), and in teachers and students (Oberle & Schonert-Reichl, 2016). Findings from my recent B.A.R.K. study (currently under review) on canine stress in working therapy dogs suggest the possibility of emotional contagion in human-to-dog interactions. In a sample of 40 canine therapy teams (comprising a volunteer handler and his/her therapy dog) and using self-ratings of handler stress and observational ratings of canine stress (by a researcher in the lab, the handler, and student clients visiting stations), correlational findings indicated that those handlers who arrived to a session with elevated stress were more likely to have therapy dogs whose stress levels were elevated at the end of the session. Based on these correlational findings, we cannot say for sure that the handler’s stress is traveling down the leash to the dog. In other words, we have not yet established that the handler’s stress is causing increases in the dog’s stress. However, this finding is in contrast to the typical pattern we found for therapy dogs who, for the most part, did not experience changes in their pre-to-post session stress levels and whose overall stress levels were low. These findings provide initial evidence to suggest that emotional contagion may be an important factor affecting the well-being of therapy dogs.  


The Importance of Canine Stress Education

Increasingly the field of Human-Animal Interactions has emphasized the importance of safeguarding the welfare of the animals working in sessions (Evans & Gray, 2012; Hatch, 2007; Iannuzzi & Rowan, 2015). To increase awareness around canine well-being and to educate the clients making use of the B.A.R.K. program at UBC, we initiated a Canine Stress Education Campaign.  This consisted of a short animated video (in production currently), handler training on identifying canine stress indicators during our orientation sessions, and the creation of a user-friendly educational poster to help educate students around the indicators of canine stress.  We all bear a responsibility in helping safeguard the well-being of working dogs on campus and therapy canine programs must ensure that human well-being doesn’t augment at the expense of canine well-being.




  1. Albercht, C. M., & Weyerer, J. (2012). Salespeople’s job stress: Exploring stress contagion from salespeople to customers. Asia-Pacific Advances in Consumer Research, 10, 305-307.
  2. Binfet, J. T., Passmore, H. A., Cebry, A., Struik, K., & McKay, C. (2018). Reducing university students’ stress through a drop-in canine-therapy program. Journal of Mental Health. (early online edition) doi: 10.1080/09638237.2017.1417551
  3. Binfet, J. T. (2017). The effects of group-administered canine therapy on first-year university students’ well-being: A randomized controlled trial. Anthrozoos, 30, 397-414. doi/abs/10.1080/08927936.2017.135097
  4. Binfet, J. T., & Passmore, H. A. (2016). Hounds and homesickness: The effects of an animal-assisted therapeutic intervention for first-year university students. Anthrozoos, 29, 441-454. (IF = 1.017, Supported by UBC Okanagan Internal Research Grant, 70% contribution)
  5. Binfet, J. T., Trotman, M. L., Henstock, H. D., & Silas, H. J. (2016). Reducing the affective filter: Using canine-assisted therapy to support international students’ English language development. BC Teaching English as an Additional Language, 1, 18-37.
  6. Evans, N., & Gray, C. (2012). The practice and ethics of animal-assisted-therapy with children and young people: Is it enough that we don’t eat our co-workers? British Journal of Social Work, 42, 600-617.
  7. Hatch, A. (2007). The view from all fours: A look at an animal-assisted activity program from the animals’ perspective. Anthrozoos, 20, 37-50.
  8. Huber, A., Barber, A. L. A., Farago, T., Muller, C. A., & Huber, L. (2017). Investigating emotional contagion in dogs (Canis familiaris) to emotional sounds of humans and conspecifics. Animal Contagion, 20, 703-715.
  9. Iannuzzi, D., & Rowan, A. N. (1991). Ethical issues in animal-assisted therapy programs. Anthrozoos, 4, 154-163.
  10. Lavee, Y., & Ben-Ari, A. (2007). Relationship of dyadic closeness with work-related stress: A daily diary study. Journal of Marriage and Family, 69, 1021-1035.
  11. Oberle, E. (2016). Stress contagion in the classroom? The link between classroom teacher burnout and morning cortisol in elementary school students. Social Science & Medicine, 159, 30-37.

About the Author:

Hailey Silas is a fourth-year biology student graduating in June with B.Sc. honors in biology from the University of British Columbia. She will be attending veterinary medical school starting in the fall, following which her goal is to complete a Ph.D. Having worked in a parasitology lab at the University of Calgary and UBC’s dog therapy program B.A.R.K., she looks forward to continuing research as part of her DVM training.


Interested in learning more about this topic? Be sure to check out the related symposium chaired by B.A.R.K. Director, Dr. John-Tyler Binfet, at the 2018 ISAZ Conference in July! The symposium, entitled, “Therapy Canines: Screening and Assessment, Safeguarding Well-Being, and Innovative Programming,” will provide an overview of three dimensions of working with therapy canines and will include sessions on therapy handler and canine screening and assessment criteria, the importance of safeguarding canine well-being during sessions, and an overview of innovative programming that sees therapy canines boost confidence and leadership in young children.

The ISAZ Student Blog is posted quarterly  and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply.


Tickling Rats for Superior Science

By Megan LaFollette

When I meet new people, they usually ask me what I do for a living. I love the opportunity to answer, “I study the intersection of animal welfare and human-animal interaction, specifically rat tickling” People are always curious to hear more, although sometimes they think I must be joking. Surely I don’t really tickle rats for my job!

Rat tickling? What is that? Why would you do that?

Rat tickling is a technique that humans can use to mimic rat rough-and-tumble play and interact with rats [1]. It’s similar to if you’ve ever played and run around with your dog, feinting, dodging, and getting down low, maybe wrestling a tad. Similar to dogs, juvenile rats play by running around and taking turns wrestling with one rat on top of the other. Obviously, we can’t wrestle a rat with our whole body, we would crush them! But we can use our hand to mimic rat play, which is the technique of rat tickling.

Researchers and pet rat owners tickle rats for a couple of reasons. The reason I am most interested in is to improve rat welfare. Initially, when we interact with rats they are afraid of us. For lab rats especially, this fear continues when scientists do things like give them injections, which can be common in scientific studies. This fear can cause stress, anxiety, and possibly interfere with scientific results. Fortunately, rat tickling can help. By tickling rats, we can reduce their fear of humans, decrease stress during injection, and increase positive emotions [2].

Is rat tickling really scientific? It seems a little silly to me.

Rat tickling is a scientifically based technique. As my colleagues and I showed in our recent systematic review about rat tickling, there have been over 32 articles and 56 experiments that use rat tickling [3]. Several of these articles looked at the welfare benefits of rat tickling. Others focused on using rat tickling to study and model positive emotions. For example, does being predisposed to being happier help in coping with stress? Scientists have used rat tickling to help answer this question [4]. They found that indeed, some rats consistently respond better to tickling than others (thought to be inherently happier) and these rats were more stress-resilient than those who respond more negatively to tickling (thought to be inherently less happy).

Do rats really like tickling? It looks pretty rough to me.

Rat tickling is supposed to be a rough and rambunctious; after all it mimics rat rough-and-tumble play. Almost all of the 22 experiments comparing rat tickling to other types of rat handling show that tickling rats is positive. To be specific, rat tickling results in increased positive vocalizations, faster approach to humans, and more positive responses to handling, as well as decreased anxiety.

Seeing positive vocalizations in response to tickling is a particularly exciting result. Rats make ultrasonic vocalizations in the 50-kHz range when they have positive experiences, and these vocalizations are therefore thought to reflect positive emotions [5]. Some scientists even think these 50-kHz ultrasonic vocalizations are actually analogous to human laughter; so it is not inaccurate to say that rats laugh when you tickle them [6].


  1. Burgdorf J, Panksepp J. Tickling induces reward in adolescent rats. Physiol Behav. 2001;72: 167–173. doi:10.1016/S0031-9384(00)00411-X
  2. Cloutier S, Panksepp J, Newberry RC. Playful handling by caretakers reduces fear of humans in the laboratory rat. Appl Anim Behav Sci. 2012;140: 161–171. doi:10.1016/j.applanim.2012.06.001
  3. LaFollette MR, O’Haire ME, Cloutier S, Blankenberger WB, Gaskill BN. Rat tickling: A systematic review of applications, outcomes, and moderators. PLOS ONE. 2017;12: e0175320. doi:10.1371/journal.pone.0175320
  4. Mällo T, Matrov D, Kõiv K, Harro J. Effect of chronic stress on behavior and cerebral oxidative metabolism in rats with high or low positive affect. Neuroscience. 2009;164: 963–974. doi: 10.1016/j.neuroscience.2009.08.041
  5. Burgdorf J, Panksepp J, Moskal JR. Frequency-modulated 50 kHz ultrasonic vocalizations: a tool for uncovering the molecular substrates of positive affect. Neurosci Biobehav Rev. 2011;35: 1831–1836. doi:10.1016/j.neubiorev.2010.11.011
  6. Panksepp J, Burgdorf J. “Laughing” rats and the evolutionary antecedents of human joy? Physiol Behav. 2003;79: 533–547. doi:10.1016/S0031-9384(03)00159-8

About the Author:

Megan LaFollette is a 2nd year PhD student at Purdue University. She works with Dr. Maggie O’Haire on Human-Animal Interaction and Dr. Brianna Gaskill on Laboratory Animal Welfare Science. Her research focuses on using rat tickling to enhance laboratory animal welfare and its effects on both rats and the humans that interact with them. Outside of her PhD, Megan is an avid traveler and loves the pursuit of acrobatic yoga.


The ISAZ Student Blog is posted every-other month and each post is authored by a different student member of the International Society for Anthrozoology. Interested in authoring a post? Please see our submissions page for details on how to apply.

Do You Believe in Dog?

We here at Becoming an Anthrozoologist would like to extend a special thank you to our friends at Do You Believe In Dog?, who recently featured Becoming an Anthrozoologist on their fantastic (and very popular) canine science blog. Thanks in part to their help, just two months after we launched Becoming an Anthrozoologist, we are delighted to announce that the blog has been visited over 800 times! Thanks again to Mia and Julie at Do You Believe in Dog?, and to everyone for reading. Stay tuned for the next edition of Becoming an Anthrozoologist in January.