Touch, in dogs, is the only other sense that functions fully at birth. Whereas in humans the skin receptors respond to pressure, vibrations, mechanical and thermal stimulation, pain, and many others, dogs experience four primary types of sensations: pressure, temperature, pain, and proprioception (a sense of where one’s limbs are).
The main difference between man’s and dog’s touch is the presence of specialised whiskers (known as vibrissae). Vibrissae are present above the dog’s eyes, below his jaws, and on his muzzle. They are sophisticated sensing organs.
Vibrissae are more rigid and embedded much more deeply in the skin than other hairs, and have a greater number of receptor cells at their base. They can detect air currents, subtle vibrations, and objects in the dark. They provide an early warning system for objects that might strike the face or eyes, and probably help direct food and objects towards the mouth.
A dog doesn’t need to feel environmental stimuli directly on the skin, because each hair on his body has a receptor (known as mechanoreceptor) nerve at its base. The nose pad has high concentrations of sensory nerves, which are also found at the base of the vibrissae. The pads of the feet have sensory nerves which respond to vibration.
Besides containing the nerves associated with feeling, the skin acts as the body’s first line of defense against bacteria and toxins, helps to control moisture loss, and protects the body from extremes of temperature.
Touch is an important form of communication with other dogs and with humans – studies have shown that stroking reduces pulse rate, blood pressure, and states of arousal, especially if carried out by someone whom the dog knows and trusts.
Touch is a protective adaptation that results in feelings of pleasure or discomfort when something stimulates pressure and temperature-sensitive nerve endings. These sensory nerves inform the brain if something feels good or painful, or is too hot or too cold, so that the dog can respond accordingly.
Canine behaviour consultant and trainer
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