The dogs were generally “less stressed” when they heard music, and they showed a slight preference for reggae and soft rock, said co-author Neil Evans, a professor of integrative physiology. Motown got the most paws down, though not by much. But the range of responses to the genres was mixed, he noted.
“What we tended to see was that different dogs responded differently,” Evans said in an interview. “There’s possibly a personal preference from some dogs for different types of music, just like in humans.”
But the results make a strong case for the use of music as a calming technique in shelter settings, he said. That’s important because animal shelters, with all their noise and unfamiliarity, can be scary for dogs. And stress can cause dogs to cower, bark loudly, shake or otherwise behave in ways that make them less likely to be adopted.
“We want the dogs to have as good an experience as they can in a shelter,” said Evans, who added that people looking at dogs might also like hearing music. And those people “want a dog who is looking very relaxed and interacts with them.”
The study, published in the journal Physiology and Behavior, built on previous research by the same team that found shelter dogs hearing classical music bark less and lie down more, signs of relaxation. But by the seventh day of classical, the benefits to the dogs in that study had worn off, Evans said, indicating that “the animals were getting habituated with the music, or possibly getting bored.” That’s what led the researchers to try the varied genres.
Previous studies have found that music can benefit other species, including captive elephants and dairy cows. Other research involving kenneled dogs supports the chill factor of classical and suggests they are not fans of heavy metal, which seems to induce body shaking in pooches. Shelter dogs also appear to find audiobooks soothing.
Evans said the next question for his team is what exactly dogs like or dislike in music. Are they fans of repeating motifs? Are there particular instruments they find pleasant, or specific tempos?
For the time being, the Scottish SPCA says it’s been convinced of the good music can do for its residents, and it’s now piping tunes into two centers in Glasgow and Edinburgh.
“Having shown that variety is key to avoid habituation, the Scottish SPCA will be investing in sound systems for all their kennels,” the charity said on its website. “In the future, every center will be able to offer our four footed friends a canine approved playlist with the view to extending this research to other species in the charity’s care.”
Speaking of other species: Evans said some of the university’s undergraduate students are investigating the effects of music on cats. But, he said, felines “are not as appreciate of wearing” heart rate monitors that dogs happily sport, so the physiological part of the research is focused on cortisol levels. “They’re just slightly more difficult to work with.”