May 9, 2007 —Domesticated animals often show signs of pleasure and relaxation when being rubbed, massaged or otherwise petted by people. Now researchers think they know why.
The research also suggests how owners might best show affection to their pets. The secret is to think like the animal.
A team of French and Austrian scientists found that cows relax, to the point that their heart rate lowers, when petted in body regions they often target when grooming each other.
"This suggests that cows may in part perceive human stroking of body regions often licked similarly to social licking," the researchers wrote in their study, which has been accepted for publication in the journal Applied Animal Behavior Science.
They believe the findings could also apply to cats, dogs, farm animals and even rats.
Claudia Schmied, a scientist at the Institute of Animal Husbandry and Welfare at the University of Veterinary Medicine in Vienna, and her team analyzed prior research on the petting of a wide array of animals before conducting their experiment with cows.
Handlers stroked 30 Brown Swiss and 30 Austrian Simmental cows in three different body regions: the top of the back, just above and below the neck, and along the side of the chest. Cow heart rates were monitored during the sessions. A control cow group experienced a human presence but no stroking.
The researchers observed that the cows stretched out their necks and let their ears fall — signs of deep relaxation — when stroked in parts of the upper back and the neck areas that cows often reach when they lick each other. Lower heart rates confirmed these observations.
Stroking the side of the chest, and simple human exposure, did little to relax the cows, which even appeared slightly agitated with a person just hanging around.
