Dogs are always overjoyed when an absent family member returns. The greeting can look the same whether the time apart is five minutes or five days. Talk about living in the present. Maybe that’s a lesson we could learn from our pets. My dogs always run up and take a good sniff to see where we have been. I always imagine they’re taking in the scents of our recent excursions. Did we go for a walk on the levee without them? To a friend’s house?
After an initial sniff, the butt and tail wag and wiggle to show how glad they are that we made it back again. If we wiggled and wagged our rear ends as hard as my nephew’s dog, Luke, we would definitely suffer a back injury. His tail is docked, (he’s a German wire hair pointer) and his posterior action makes up for it.
After the tail wagging and smiling, then a serious sniff might be in order if the initial sniff warranted another pass. Are they thinking, “No, it smells like that same place they go every day that we never see?” I’m sure they are used to the smells of our workplaces, but I always wonder what they think of the different scents of all the dogs and cats I see daily.
You may wonder how sensitive a dog’s sense of smell really is. You see, a dog has 300 million smell receptors compared to our five million. On top of that, the area of the brain in charge of analyzing the smells is 40 percent larger than ours. Some estimate their sense of smell is more than 10,000 times better than ours. If we can smell a teaspoon of sugar in a cup of coffee, they could detect the same amount in a million gallons of water. (Two Olympic size swimming pools. Honest, I looked up the amount!)
Another example would be our experience in smelling a cooking stew. We may know it is chicken or beef, but the dog would know ALL of the ingredients, including a pinch of this and that. That’s why dogs make good drug, bomb, search and rescue, seizure and even blood sugar detectors. Just watch your dog sniff the air, inhale from air vents in your car or outside your car window. They are enjoying the fresh air, breeze and the local news.
Cats also have an excellent sense of smell, but it can’t compare with their canine companions. The feline smeller is only 15 times better than ours. Mokie, my grey tabby, will often come up for a smell and may stick her lip out and stay motionless for 30 seconds. This behavior, called the flehmen response, is also common in horses and cows upon smelling some particular odor in urine. (Mokie always reminds me that once I’m home, it’s time to change my clothes.) When Mokie rubs her cheek up against my legs and pants, it serves several purposes. She’s showing her affection by rubbing and purring, and leaving her scent on my clothes to mark her territory.
The sense of smell in cats seems more directed toward knowing who is in their territory, where historically dogs used their highly developed sense of smell to track prey. That’s why some cats prone to anxiety will spray their scent on walls, garbage cans, furniture or plastic when they are stressed. (However, spraying can also be a sign of a urinary tract infection – check with your vet.) If a feline or human bully in their area upsets them, they will let us know by extra rubbing or spraying. The smell of the scent from their cheeks and urine covers other scents, comforts them and lets them know everything is OK.
However, angry cats have been known to pee or poop on human clothes, belongings or beds to let them know how they feel. When introducing new cats into a household, it’s sometimes necessary to make sure they have separate litter boxes. It’s not a matter of sanitation, but smell. The odor of different cats in their box may upset them. I don’t think I would like it so much either.
Greg Martinez, DVM, has worked at Gilroy Veterinary Hospital with Dennis Harrigan, DVM, for more than 30 years, and with Marc Van Every, DVM, for three years. Over the last 10 years, he has become very interested in the natural role of nutrition in treating chronic medical problems and to prevent future ones.
