Dogs laugh?

Do dogs laugh and is it useful for human's to mimic their laughter?

Article excerpts
Research done by Patricia Simonet at Sierra Nevada College in Lake Tahoe looked at laughter sounds in dogs. Simonet's team investigated the question (do dogs laugh) by standing in parks with a parabolic microphone that allowed them to record the sounds that dogs made while playing from a distance. In describing the laughter sounds of dogs she says that, "To an untrained human ear, it sounds much like a pant, 'hhuh, hhuh." When the recordings were analyzed she found that this exhalation, bursts into a broader range of frequencies, than does regular dog panting.

Simonet noticed that when she tried to imitate the laugh panting sounds of dogs it seemed to have a positive effect on the animals hearing it. -- She confirmed the positive effects of this laugh sound in an experiment on 15 puppies, which romped for joy simply upon hearing the recorded canine laugh. More recently Simonet was able to show that these same sounds helped to calm dogs in an animal shelter.

--(source) Article, 'Do Dogs Laugh?', Psychology Today. Canine Corner: the human-animal bond by Stanley Coren, Ph.D.