Dogs at work can not only bring down stress levels among their owners, but they can also help make work more satisfying for other employees as well, according to the study in the latest issue of the International Journal of Workplace Health Management.

"The bottom line is that dogs in the workplace can make a positive difference," said professor Randolph Barker of Virginia Commonwealth University's business school, who led the five-member research team.

"They may in fact be a great buffer to the impact of stress" on productivity, absenteeism and employee morale, Barker told AFP in a telephone interview from Richmond, Virginia.

Previous studies have underscored the benefits of therapy dogs in hospitals and nursing homes.

But Barker said his team's investigation was among the very first to focus specifically on dogs in the workplace and their potential as "a low-cost wellness intervention readily available to many organizations."

For a week, the researchers monitored day-shift staff at Replacements Ltd., which sells dinnerware from a fast-paced facility in Greensboro, North Carolina that is the size of seven American football fields.

For more than 15 years, Replacements has allowed its 550-odd employees to bring their dogs to work.

Seventy-six volunteers, from the president on down, were split into three

groups: those who brought their dog to work, those with a pet who did not, and those with no pet at all.

Saliva samples upon awakening verified that all participants started their workdays with low stress hormone levels.

In the ensuing hours, however, self-reported on-the-job stress levels fell among those with their dogs by their side -- and grew for those who either left their animals at home or who had no pet at all.

"The differences in perceived stress between the days the dogs were present and absent were significant," Barker said. "Employees as a whole had a higher job satisfaction than industry norms."

In passing, the researchers also detected that dogs inspired greater personal interaction -- for instance, when staff without pets offered their dog-owning colleagues to walk their dogs.

Not everything was perfect. Among the comments collected by the researchers included "some dogs are disruptive, "allergies problems for some" and "dogs should be well-behaved and quiet."

But Barker said his team, partly funded by Virginia Commonwealth University's center on human-animal interaction, is keen to expand its work to include more and different workplaces over greater lengths of time.

They also want to delve into how stressful it can be for dogs to hang around a human's workplace all day.

The Humane Society of the United States says there are 78.2 million dogs across the country (outnumbered by 86.4 million cats), with more than one in three households owning at least one dog.

Two years ago, it said, researchers at Central Michigan University found that when dogs were present in a group, employees were more likely to trust each other and collaborate more effectively.

To encourage more dog-friendly policies among employers, the Humane Society published a book in 2008 titled "Dogs at Work: A Practical Guide to Creating Dog-Friendly Workplaces." (AFP)