On average, a dog has approximately 200 million scent receptors in his nose. (Dachshund: 125 million; Fox Terrier: 147 million; German Shepherd: 220 million)
Dogs only need 1 part per trillion to locate an odor.
The sniff is actually a disruption of the normal breathing pattern. Sniffing is accomplished through a series of rapid, short inhalations and exhalations.
Dogs track to the source by following the ever-increasing density of the odor molecules.
Human and canine noses can become saturated with particular odors, called “olfactory fatigue”, which includes a temporary loss of sensitivity.
Dogs have another “scent receptor” in their mouth called the Jacobson’s Organ, or vomeronasal organ, which detects pheromones.
Viral and bacterial infections, fungal disease, allergies, trauma, tumors, exposure to toxic chemicals and certain medications can impede the sense of smell.
The sense of smell is closely linked to the emotional state of mind and can evoke strong emotional reactions in both humans and dogs.
The dog’s body temperature rises during an intense searching session. 101.5 degrees F is the average body temperature of a dog. Normal recorded temperatures of working dogs are between 100 and 108 degrees F.
