Ever wonder why your pooch insists on sniffing butts? You can find the answer to this question and much more in veterinary specialist Justine Lee's "It’s a Dog’s Life…but It’s Your Carpet." Here's an excerpt:

Is your dog’s nose an accurate indicator of his overall health?
The truism goes that the eye can lie, but the nose knows. However, I think that when Anonymous wrote this gem, she was referring to the guilty party with the perfume-scented collar rather than the hairy housemate in the leather collar. In general, Fido’s nose is not an indicator of how sick or healthy he is. Check out your dog’s nose. You may notice it fluctuates between slightly dry to soft and moist, depending on the day, weather, and humidity. A dog’s nose usually feels wet due to the lateral nasal glands’ secretions that keep it moist.1 There is, however, no direct correlation with the health of your pet and their sniffer. If you notice that your dog’s nose is excessively thickened, cracked, or bleeding, then that might warrant a vet exam, as certain conditions, such as pemphigus or lupus, can present this way. But the dif- ference will be very obvious. Just remember this handy little rhyme: If it’s dry or wet, no vet; but if it looks sick, get hip! This should help you weed out your parental anxieties from the true emergencies.

Why do dogs like to sniff butts?
Why, hello there! Ever wonder why dogs like to sniff each other’s butts in the dog park? Dogs have two anal glands just on the inside of their rectum. They release a foul brownish discharge with a strong, unique scent. Both male and female dogs have these, and that’s why you may notice dogs “identifying” each other by a sniff of their scent glands. While this may seem crude to you, it’s the dog equivalent of a handshake and introduction. Thank dog that evolution got us out of that one.

How well do dogs smell?
Isn’t it great how Tracker can find that dead, decaying carcass in the woods from hundreds of feet away? Dogs have an amazing sense of smell, which they used to hunt and survive in the past, and to find and dig up things better left alone in the present. (“Hey Ma! Look what I found!”) For comparison, humans have approximately 5 million olfactory sensory cells that we use to smell with, while dogs can have up to 220 million. That’s the reason why police use bloodhounds and drug dogs to make their busts: their sense of smell is a million times stronger than a human’s!2 I once had a patient named “Kilo” who was a police dog; as his name suggested, his schnoz was able to sniff out illicit drugs behind drywall, in crawl spaces, and in all the hidden spots where druggies hide their stash. Unfortunately, he started passing out when he got excited, due to a heart arrhythmia, but since we put a pacemaker in him, Kilo is back to bustin’ the bad guys! Given the state of urban living today, I suppose we should be thankful our sniffer isn’t stronger.

Why don’t dogs get hairballs?
Unlike cats, dogs are not particularly fastidious when it comes to cleaning themselves—remember, they roll in dead, decaying animals, race into murky bodies of water like they’re on fire, and don’t mind eating each other’s poop. I’m not quite sure why dogs tolerate being dirty, stinky, and messy, but like many children and some human males, they just don’t seem to mind. Cats, on the other hand, groom excessively (and therefore don’t require baths). They have a naturally barbed tongue that grabs shedding hair, which they later purge all over your carpet. Because dogs don’t groom (or don’t care), they don’t develop hairballs. Instead, they develop weird smells and doggy dreadlocks as they are waiting for you to brush and bathe them!

Why do dogs shed?
My boyfriend thinks that I leave my hair everywhere to purposely “mark” my territory, but since he only dates brunettes, it wouldn’t really help me. Hair isn’t effective as a territorial flag, anyway—stray winds and foot traffic make it unlikely to stay put. Strategically abandoned clothing, on the other hand . . . well, let’s just say we all shed things for different reasons.

Dogs shed to help them regulate their temperature as the seasons change. Since your little furball doesn’t have the option of donning a warm parka in the winter or getting buck naked in the summer, his coat has to be able to adapt to environmental changes. In extreme conditions, not only does hair protect him from cold, heat, and damaging UV light rays, but it also provides a protective barrier against any skin trauma while he’s running through the woods, playing with other dogs, or getting bitten by insects.

During periods of short daylight, your dog’s brain tries to maintain a thicker coat for warmth. He’ll even grow in “secondary” hairs in the fall and winter to add more warmth. In the spring and summer months, you may find yourself Swiffering your house much more frequently, because your dog’s brain is now affected by the longer photoperiod (the amount of daylight he is exposed to), and he will begin to shed more aggressively. Often, he will only shed his shorter undercoat and develop a coarser, longer hair coat during the spring and summer; this helps act as a protective buffer and provides a cooler layer around the skin. For this reason, we don’t advocate shaving dogs that spend time outdoors, as they will (a) sunburn, (b) get attacked by insects, (c) get hotter (despite looking naked), and (d) get ridiculed by neighborhood dogs.

How do I make Fido shed less?
My non-vet friends always fearfully ask, “Is something wrong with your cat?” before they reach over to pet one of them. The thing is, I often shave my short-haired cats down to a “peach fuzz” level. I do it because I can’t stand the extra hair shedding in the house, and no, it’s not infectious (unless I don’t like you). Maybe it’s not a typical, normal, healthy way to decrease shedding in the house, but hey . . . I’m a vet, and the clippers are just too accessible.

And to be honest, aside from constant clipping and grooming, there’s not much you can do besides shaving to stop shedding at the source. While there are liquids, ointments, liniments, sprays, and other supplements advertised, don’t believe the hype— otherwise we’d all be using it, and several iconically bald actors would be short a career. In general, dogs shed more in the spring and summer, so it’s important to brush Fido daily (or at least weekly) in these months, particularly if he’s got medium to long hair. The more hair you brush or rake out (with those circular scrapping brushes), the less it will cling to your furniture, floor, and feet like a bad sympathy prom date. There are a few breeds that don’t shed, such as the poodle or bichon frise, but even these dogs need to be groomed frequently.

Why do dogs shed more at the vet?
Even the courageous Underdog gets nervous at the veterinary clinic, and you may notice that he starts shedding massive amounts of hair when he walks in. This is the fight-or-flight instinct kicking in. Not only does the heart rate increase from stress, but so does the respiratory system—he starts panting or breathing harder in an attempt to get more oxygen into his lungs. Your dog recognizes where he’s at, and his body is preparing for escape mode (“Help me! I sense a mean vet coming in!”). At the same time, all the blood vessels and hair follicles are dilating to allow blood to flow to the escape muscles, and for this reason hair may start to shed like mad. Don’t worry too much (or your own hair may start to come out); signs should resolve shortly after you bring him home. And hopefully next time, your dog will remember that there are no mean vets in existence—or so we like to think!

Why do dogs “peel out” and scrape their back legs after urinating or defecating?

Dogs have scent glands in their paw pads, and often scrape their back legs to mark their territory after they urinate or defecate. My dog, JP, a pit bull that I rescued from the ghetto streets of Philly, loves to scrape his back legs after he poops, it’s his manly (albeit neutered) way of telling other dogs that “JP was here, and he keeps it real.” While “peeling out” is a predominant trait among “intact” males (read: the testicled ones), neutered males and even females have been known to do this as well. They’re basically trying to tell the next dog that they were here and that this was “their spot.” Remember lunchtime in the high school cafeteria? Sort of like that, but with the added bonus of public defecation.

Incidentally, male deer will also do this (it’s called “scraping”), and hunters use the scrape mark as identification that a buck is in the area. When I take JP out in the woods during the fall (in fluorescent orange garb, of course), I don’t exactly mind that he fakes out the hunters by scraping the ground. I just wish that PETA were paying him!

Is Fido’s front limb an arm or a leg?
Anatomically, we generally consider the forelimb an arm and a hindlimb the back leg. This is because the anatomy of most species is similar, with the exception that man became upright. Your dog’s front leg or arm consists of the humerus, radius, and ulna—like your arm—while his hind leg consists primarily of the femur, tibia, and fibula. So while you are bipedal, you still have a similar structure; you just look more like a monkey.

Do dogs get goose bumps?
Goose bumps, otherwise known as piloerection, are a fancy way of saying that the hair is standing erect in the follicle. Hello! While it’s not commonly called “dog bumps,” goose bumps are harder to see in Fido due to all that fur. Nevertheless, Fido can still get them.

Humans often get goose bumps from cold exposure or fear. Since Fido has a nice, thick warm coat of fur to keep him warm, he rarely develops goose bumps from cold exposure. Rather, dog goose bumps may be due to feeling nervous, fearful, or demonstrating aggression toward another animal or person. Fido is basically trying to make himself appear larger and fluffier (i.e., “Look at how big I am, stay away!”) to intimidate the stranger.

The development of goose bumps is actually a complicated neurotransmitter reflex, and has been associated with an affective defense behavior.3 Goose bumps are just one of the many signs seen with this defensive behavior. Dogs may also show a lowered stance, a slow “hunting” gait toward the “attacking animal,” an upright (but not wagging) tail, and goose bumps over the shoulders and tail rump area. If you notice “dog bumps” in the form of raised hair over Fido’s neck or rump, approach with caution!

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