Opinion

Cats have an intense sense of 'smell'

Someone recently asked me if cats could “smell” better than people. Yes, humans have about 5 million scent receptors compared to 200 million scent receptors in cats. Humans can smell the roses, but cats can smell the person or animal that stopped by to smell those roses.

When a cat sniffs something intensely, you may observe a “flehmen response” — a partially open mouth and funny grimace across the cat's face. Cats have sensory organs in their mouth called Jacobson organs. These two fluid-filled sacs, located on the roof of their mouths and behind their teeth, connect directly to the nasal cavity. Contrary to the displeased look on their faces, cats might actually enjoy this oral smelling. They are purposely drawing air into their mouths to sniff an odor more deeply, like someone who might sniff wine before drinking it.

Just like dogs, cats learn about their environment through smell. Cats have pheromones in their saliva, feces and urine. Pheromones are secreted chemicals that trigger a response in animals of the same species. Thus, the reason why both dogs and cats smell stuff we would never put our noses near. Scent glands on a cat's cheeks and paws also mark territory as they rub against people or furniture or claw on trees or your favorite chair. Urine marking tells other cats to stay away.

Cats also have more scent receptors than some dogs. In “Understand a Dog's Sense of Smell for Dummies,” the book reports that Bloodhounds have about 300 million scent receptors; German Shepherds and Beagles have about 225 million. But cats have more scent receptors than Fox Terriers (147 million) and Dachshunds (125 million).

The difference is, while dogs may employ their super snouts in bomb and drug-sniffing or missing person activities, cats rely on their scent receptors to secure their relationships and territory. Whether they rub against a new piece of furniture or your pant leg, they are essentially marking and saying, “This is mine.”

Because we are not as in tune to felines, we sometimes may trigger puzzling reactions from scent sensitive cats.

If, for example, you clean a litter box with a citrus-smelling cleaning product and your cat refuses to use it, it's not because its clean, it's because citrus is a repellant for cats.

If you come home with the smells of other cats and dogs on your clothes, your cat may have a “flehmen response.” Be careful not to leave those clothes on the floor. Cats are known to urinate on dirty laundry or bed sheets to reclaim their territory.

Basically, felines use smell to communicate. We should listen.

Send your pet stories and questions to Cathy M. Rosenthal, c/o Features Department, San Antonio Express-News, P.O. Box 2171, San Antonio, TX 78297-2171 or cathy@petpundit.com. Cathy's advice column runs every Sunday. You can read her blog, Animals Matter, at www.sapaws.com.