'Love hormone' makes dog man's best friend

Melbourne: Ever wondered why dogs exhibit so much friendly behaviour towards humans and so easily follow commands given to them? That's thanks to the "love hormone" oxytocin, reveals a new study.

The hormone oxytocin is produced by all mammals and is linked to bonding.

Dogs given extra doses of oxytocin - the same hormone linked to pair-bonding in humans - were better at performing simple tasks, indicating they were better at "reading" their owners, according to a study published in the journal Animal Cognition.

"So my hypothesis is that over the course of domestication, something happened within the dog's brain that allowed them to understand human social cues," lead researcher Jessica Oliva was quoted as saying.

Researchers from the Monash University in Melbourne, Australia, studied 75 dogs over 12 months and gave them a nasal spray of oxytocin to see if the hormone had any affect on the dogs' ability to complete simple tasks.

The dogs given oxytocin were better able to complete simple tasks than those given a simple saline spray, the researchers found.

The dogs' response to the hormone could offer important clues about how dogs evolved to become "man's best friend," researchers said.

Dogs are better able to complete certain tasks than their ancestor, the grey wolf, even when the wolf is brought up in a domesticated setting, Oliva and other study authors said.

Researchers theorised that since both humans and dogs usually produce more oxytocin as they interact, the presence of the hormone indicates that dogs evolved into being the perfect human companion because that chemical bond allowed them to better "read" human commands.

The drug, which occurs naturally in the body, has been found to foster connection between humans, in addition to lowering blood pressure and other indications of physiological stress.