A CAT'S SENSE OF SMELL IS AS POWERFUL AS A DOG'S, BUT USED FOR DIFFERENT PURPOSES
By Kim Campbell Thornton and Dr. Marty Becker
How important is scent to cats? More than you might think. No one has ever been silly enough to try to put them to work finding people or substances by scent, but cats have a keen sense of smell and rely on it heavily. Unlike dogs, however, who have developed an array of scent-related careers to help people, cats use their sense of smell for more personal endeavors: to establish territory and determine where they are, to identify each other, and to whet their appetites.
Odor is crucial to a cat's feeling of comfort in the home. Cats use scent to mark territory and make a place their own. Their sebaceous glands -- located primarily on the lips, chin, between the eyes and ears, at the base of the tail and around the anus -- secrete sebum, an oily substance that is odorless to us but contains scent markers that are meaningful to cats. Urine and feces also contain these scent markers.
When you see your cat rubbing his face against your body or an object such as the refrigerator (where the food comes from!), he's laying down an invisible but scented token of possession, a signal to other cats that this person, place or thing belongs to him. Urine marking is a more odorous, and less-pleasing-to-humans, means of accomplishing the same thing.
Cats also use scent to identify and greet each other. They begin by sniffing faces and then rears. Think of it as the feline version of a handshake, and don't be offended when your cat presents his butt for you to sniff. He's just being polite -- in a catly sort of way.
Odor is also strongly linked to appetite. A cat who has lost her sense of smell will be uninterested in food. That's why feline nasal infections can be more serious than they might seem. Cats can quickly go downhill if they refuse to eat. Entice them by offering stinky canned food or warming their food before giving it to them. (Stir it well to make sure there aren't any hot spots that could burn the mouth.)
Cats also have an uncommon ability to "taste" scents, with the help of some unusual anatomical features. They have two small air passages known as the nasopalatine ducts, which are located in the roof of the mouth just behind the upper front teeth (incisors). Air in the mouth passes through the ducts, which lead to the vomeronasal, or Jacobson's, organ in the nasal cavity.
If you've ever noticed your cat give something a good sniff, wrinkle his nose and open his mouth with the lips slightly retracted, you're seeing the vomeronasal organ in action. That expression, as if he's smelling something unpleasant, is called the flehmen response. It occurs when cats encounter urine or other odors that provide information to them. Nerves run between the VNO and the area of the brain that controls sexual behavior, and scientists believe that the flehmen response helps the cat to draw in and sample more of the odor. It's seen primarily in male cats and may assist them in determining a female's reproductive status. Females are more likely to display the flehmen response when sniffing their newborn kittens. Any cat may flehmen in response to the scent of catnip, the urine of other cats or to any unfamiliar smell.
Like humans, cats find certain odors to be repulsive, but their idea of what smells bad isn't the same as ours. Orange peel and mothballs are on their "do not sniff" list.
Which odors do cats love best? Catnip, of course, and, strangely, garlic and onion. And if you are lucky, your cat's favorite scent is you.
Q&A
Pets with cancer
can respond well
to chemotherapy
Q: My dog has been diagnosed with cancer, and the oncologist recommends chemotherapy. He says that chemo isn't as hard on pets as it is on people. Is that true? Will my dog lose his hair or have other side effects? -- via email
A: We're sorry to hear about your dog's diagnosis. People are often hesitant to have their dogs undergo chemotherapy -- the use of drugs to destroy cancer cells -- but it can be an effective treatment with fewer side effects than those seen in humans.
Cancer occurs when cells grow uncontrollably, causing abnormal tissue to develop. Chemotherapy drugs affect not only the abnormal and rapidly growing cancer cells, but also other areas of the body that produce normal rapidly growing cells. Think bone marrow, which produces red blood cells; the lining of the intestinal tract, which sheds old cells and generates new ones frequently; and hair, which grows rapidly. That's why people who receive chemotherapy often suffer painful or unsightly side effects such as nausea, diarrhea, hair loss and weakness. The trade-off is that the high doses they receive improve their response to therapy.
The difference in dogs and cats is the amount of chemotherapy that's given. The goal is to provide additional time but not at the expense of quality of life. Most pets do not experience serious side effects from the treatment. Sometimes they are tired afterward or may experience nausea. If that happens, the oncologist (cancer specialist) may prescribe Cerenia, a drug that helps with motion sickness in animals and can relieve the nausea and fatigue caused by chemotherapy. Mild gastrointestinal side effects can be managed with a bland diet. And hair loss is rare in dogs.
Depending on the type of cancer and how advanced it is, chemotherapy can decrease tumor size, prolong life and sometimes lead to complete remission. -- Dr. Marty Becker and Kim Campbell Thornton
THE BUZZ
Feral cats dodge coyotes
by staying close to people
-- City-dwelling feral cats have canny survival skills, according to a new study published in the online journal PLOS ONE. Lead author Stan Gehrt, associate professor of environment and natural resources at Ohio State University, says researchers monitored the health, home ranges and habitat selections of 39 feral and stray cats in the greater Chicago area, which also has a dense population of urban coyotes. They discovered the cats avoided natural areas in the city because of the coyote presence and thus caused less damage than previously thought to wildlife in parks and nature preserves. The cats also lived longer and were healthier than expected.
-- Researchers at UCLA say genetic analysis shows that European hunter-gatherers domesticated wolves more than 18,000 years ago, with the canines gradually evolving into the dogs we know today. In an article published Nov. 15 in the journal Science, Robert Wayne, a professor of ecology and evolutionary biology in UCLA's College of Letters and Science and senior author of the research, says: "We found that instead of recent wolves being closest to domestic dogs, ancient European wolves were directly related to them. This brings the genetic record into agreement with the archaeological record. Europe is where the oldest dogs are found."
-- Ferrets, especially those in shelters, are vulnerable to canine distemper virus, but The Xavier -- A Ferret Abroad Canine Distemper Fund is raising money to help ferret shelters prevent outbreaks and treat the animals if they do become ill. Plush ferret ambassadors travel the world, visiting people who make donations. Headquartered on Facebook, the fund was established last year and is administered by the nonprofit Ferret Association of Connecticut. It provides vaccination grants and emergency medical grants to any ferret shelter in the world that belongs to The Xavier -- A Ferret Abroad Facebook group. -- Kim Campbell Thornton
ABOUT PET CONNECTION
Pet Connection is produced by a team of pet care experts headed by "Good Morning America" and "The Dr. Oz Show" veterinarian Dr. Marty Becker and award-winning journalist Kim Campbell Thornton. They are affiliated with Vetstreet.com and are the authors of many best-selling pet care books. Joining them is dog trainer and behavior consultant Mikkel Becker. Dr. Becker can be found at Facebook.com/DrMartyBecker or on Twitter at DrMartyBecker. Kim Campbell Thornton is at Facebook.com/KimCampbellThornton and on Twitter at kkcthornton. Mikkel Becker is at Facebook.com/MikkelBecker and on Twitter at MikkelBecker.