Sniffing Your Way to Better Hospital Experiences – Materials

3 - Born to Smell

Born to Smell

Dogs and cats are born to smell. A cat’s nose is often regarded as her most important sense organ, having nearly 80 million receptors in the epithelium of their nostrils. Olfaction, the act or process of smelling, is also a dog’s primary special sense. With dogs having more than 220 million olfactory receptors in their nose, compared to humans having only 5 million, it should be no surprise they have a significantly heightened sense of smell. Some dog breeds, like the bloodhound have nearly 300 million scent receptors! The sense of smell and the sense of touch are the predominant senses for a dog and they are fully functioning at birth, unlike hearing and sight, which develop later, and taste which although present at birth and connected to smell takes a back seat.

The sense of smell is a highly developed sense at birth in puppies and kittens. Newborn kittens establish a nipple preference on the nursing queen, and smell is used to guide a kitten back to his chosen site. If a young kitten wanders from his nesting area, olfactory cues will be guide him back until vision becomes the main guide at 3 weeks of age. During the weaning process, from 4-6 weeks of age, a kitten will utilize smell to find food, and distinguish between edible and inedible objects. The same goes for puppies.

Did you know dogs and cats have “nose prints,” and no two are the same? Every dog and cat nose has a unique pattern of bumps and ridges, just like humans’ fingerprints. There has apparently been some talk about using nose prints as a form of identification. This would definitely take facial recognition to a whole new level.

A cat’s sense of smell guides her to prey and tells her if food is edible or toxic. A cat’s sense of smell also stimulates her appetite. Cats have less than 500 taste buds on their tongues whereas humans have around 9000, so it’s often the smell rather than the flavor that stimulates her sense of hunger. That’s a big part of the reason why cats with respiratory infections or other nasal blockages stop eating: If they can’t smell their food, they won’t have an appetite.

Cats not only utilize their nose to locate food, but also use it as a medium to communicate. Cats have scent glands around their mouth and on the sides of their head, the pads of their front paws, and in the perianal areas near the base of their tail. These glands contain one-of-a-kind pheromones unique to each cat. Whenever they rub their head or paws against an object, it is as if they are leaving their business card for other felines to recognize and translate. We’ll explore more about pheromones later in the course.