LINKOPING, Sweden — Is there anything quite like the bond between a dog and its caregiver? Canines usually become incredibly attached to their human companions, so much so that it feels like their entire world revolves around their owners. Now, a new study conducted at Linköping University in Sweden finds that dogs even take on the stress levels of their owners.
That’s right, if you’re feeling particularly stressed out, there is a good chance your pup is feeling the same way.
The study’s authors considered the possibility that the relationship works the other way; humans take on the stress levels of their dogs, but they do not believe this is the case.
The research team set out to examine how lifestyle factors and human living companions influence stress levels in dogs. It’s already been established that humans tend to become mired in the negative emotions emitted by close family members or friends, so researchers wanted to see if the same effect was observable in dog-human relationships. Over the course of several months, dogs’ stress levels were measured via concentrations of the stress hormone cortisone using strands of hair collected from both humans and their respective pups.
“We found that the levels of long-term cortisol in the dog and its owner were synchronized, such that owners with high cortisol levels have dogs with high cortisol levels, while owners with low cortisol levels have dogs with low levels”, says principal study author Dr. Ann-Sofie Sundman in a university release.
In all, the research phase of the study consisted of 25 border collies and 33 Shetland sheepdogs. All of the dogs’ owners were women. Each owner and their accompanying dog submitted hair samples twice over the course of a few months.
Physical activity and exercise is also known to raise cortisone levels, so the research team wanted to compare the activity of the analyzed pet dogs with other dogs participating in obedience or agility competitions. To that end, physical activity readings for each of the pet dogs were also collected for a period of seven days using an activity collar.
While previous research had found that short-term cortisol levels in dogs’ saliva is in unison with their owners when they compete together, this time around researchers found that exercise in dogs does not impact long-term cortisol levels in their hair. However, stress levels among competing dogs did seem to be strongly linked to the stress levels of their owners. Researchers theorize this is due to a higher degree of active interaction between owner and dog since they probably train and exercise together on a daily basis.
Participating dog owners were also asked to fill out two questionnaires regarding both their own and their dog’s personality. These questionnaires were used to assess if stress levels were correlated with personality traits.
“Surprisingly enough, we found no major effect of the dog’s personality on long-term stress. The personality of the owner, on the other hand, had a strong effect. This has led us to suggest that the dog mirrors its owner’s stress”, explains senior author Lina Roth.
The study’s findings suggest that the closeness between a dog and owner pairing affect just how much the human influences the dog’s stress levels. Researchers caution, however, that further research is ultimately needed before any final conclusions can be drawn regarding the cause of the correlation.
Moving forward, researchers are planning on analyzing additional breeds; both dog breeds included in this study are herding dogs bred to get along well with humans and respond quickly to commands. With this in mind, it stands to reason that different breeds may exhibit different characteristics. Another possible avenue of research is to investigate whether or not the sex of the owner plays a role.
“If we learn more about how different types of dog are influenced by humans, it will be possible to match dog and owner in a way that is better for both, from a stress-management point of view. It may be that certain breeds are not so deeply affected if their owner has a high stress level”, Dr. Lina Roth concludes.
The study is published in the scientific journal Nature.