Research: Dogs go gray due to stress

Impulsivity, anxiety associated with early graying

CHICAGO — Few would dispute that the stress of 2016 likely led to premature gray hair in humans. Now comes research, conducted in part by Northern Illinois University, showing that stress in dogs can turn them prematurely gray, too.

The research, published in the December issue of Applied Animal Behaviour Science, analyzed questionnaires of 400 dog owners at a variety of venues in the Denver area to determine if their pets exhibited stressful behavior.

Researchers then photographed the dogs and handed the photos to independent raters, who gauged the dogs’ amount of gray hair.

“Both anxiety and impulsivity were significantly associated with premature graying in dogs between 2 and 4 years of age,” the report concluded.

“Specifically, dogs presenting a greater extent of anxiety and impulsivity were more likely to present premature muzzle grayness than dogs showing less anxiety and impulsivity.”

The report’s authors, who included NIU professor Thomas Smith, NIU alumna Camille King and prominent animal researcher and author Temple Grandin, also found that dogs’ “fear responses” to loud noises, unfamiliar animals and new people were “significantly associated with increased muzzle grayness.”

The research also showed that female dogs were “significantly more likely” than male dogs to show gray in their muzzles.

The results follow a 2014 report by King, Smith and Grandin, whose research showed that pressure wraps markedly decreased heart rates in anxious dogs.

Smith, a professor of education who helped with data analysis of the findings, said he was surprised.

“I had a certain amount of skepticism about the idea” going into the study, Smith said last week. “But when we analyzed the data, it jumped out at me right away.”

Grandin, an animal science professor at Colorado State University, said the “original, unique study” gives owners of prematurely gray dogs a chance to take a different approach in their animal’s care.

“Maybe you let the nextdoor neighbor keep the dog while you’re at work,” Grandin said.

King, the lead author who earned her doctorate at NIU and now runs an animal behavior practice near Denver, said the results confirmed her observations over almost two decades of working with dogs. Those exhibiting stress would present gray muzzles as early as 2 years old, she said.

More study is needed, she and Grandin said, on whether anxiety at being left home alone or impulsivity are the more significant.

King encouraged dog owners who notice their young pets turning prematurely gray to visit a veterinarian or animal behaviorist for advice on how to ease their animal’s stress.