Why Dogs Eat Poop (and Other Gross Questions Answered) borrowerd from the Rover.com Blog

We love our furry friends but let’s be honest: sometimes they can be downright gross. From eating poop to smelling butts to stinky breath, we’re decoding why dogs do the icky things they do.

1. Why Do Dogs Sniff Butts?

Sniffing butts is normal and acceptable dog behavior, but it makes some dogs nervous. 

It’s the canine handshake—butt sniffing is the official accepted greeting in the dog world. Did you know dogs can instantly pick up on things like age, gender, health, and even social standing just from catching a whiff?

“When one dog sniffs another dog, they can sense that dog’s hierarchy in the pack,” certified behaviorist and owner of Pawtopia Dog Training Colleen Demling says. “It’s just like when someone walks into a room—you can draw some conclusions about them including general social standing.”

Even though butt sniffing is a proper dog-to-dog greeting, some dogs are more comfortable with it than others.

“If it’s a really dominant dog and he thinks another dog is sniffing inappropriately, it can be offensive,” Demling says. “Sometimes it’s a dog who is socially not sure what is going to happen—they’ll get stiff in anticipation of something going wrong. Some dogs just don’t like it because it’s invading their space.”

“If it’s a really dominant dog and he thinks another dog is sniffing inappropriately, it can be offensive.”

Since the other dog can sense that uneasiness, it can turn into a stand-off, so some owners try to prevent dogs meeting by butt sniffing.

“Letting a dog get his butt sniffed is normal, appropriate, and should be allowed,” Demling says. “By trying to prevent it, you can sometimes increase aggression. Any greeting should be handled with calm body language by owners—like a loose leash—and lots of positive praise for good behavior.”

Although butt sniffing is a normal way dogs communicate, our furry friends sometimes mistakingly think they can draw the same conclusions by sniffing humans, too.

“To them, it’s the same concept,” Demling explains. “They think, I sniff a dog’s butt for greetings, so I’m going to sniff a person’s butt or crotch for the same outcome, not knowing it’s different.”

Make sure you train your dog not to do this. Demling recommends three approaches:

Leave it: Demling says teaching your dog to not even go near a guest’s crotch is the best approach.

Go bedtime: “Have your dog go to a place away from the door so guests can be welcomed without the dog sniffing them,” Demling suggests.

Sit and stay: If your dog won’t go to his bed, at the very least make him sit and stay, which allows guests to come greet your dog instead of the other way around.

2. Why Do Dogs Pee on Things?

Ever wonder why dogs lift their leg to pee? They are trying to get their mark the highest possible to make it appear they are a larger dog. 

If your dog is constantly straining on the leash to sniff and pee on everything he passes, you’re not alone. Peeing on things is instinctual for dogs and is like putting up notes on the doggy bulletin board—it says, “Fido was here.”

“Dogs pee on things to gain territory—it’s saying ‘I own this property,’ or ‘I’ve been here,'” Demling explains.

If you’re part of a multi-dog household, you may notice your dogs peeing over each other’s marks.

“That’s to say ‘I’ve been here, too and I’m more in charge than you are,'” Demling adds. “They’re trying to get the highest mark on the tree.”

“Dogs pee on things to gain territory—it’s saying ‘I own this property,’ or ‘I’ve been here.'”

How about your dog stopping to pee even though he’s got nothing left?

“It’s an instinctual thing—a lot of dogs will keep doing it even though there’s no urine left,” Demling says. “It’s bred into them.”

From a training perspective, Demling suggests not allowing your dog to stop to pee on walks more than three times.

“More stops can increase territory aggression in the neighborhood because the dog thinks they own every tree,” Demling explains. “It can also increase the chance of marking in the house, even if they’re potty trained.”

3. Why Do Dogs Hump?

Some dogs could care less if another dog humps them, but humping should always be discouraged and stopped to prevent potential dog fights when a dog does mind being humped. Some pet parents make the mistake of dismissing humping as a natural sexual behavior or inclination when in fact, it’s a behavior to assert social dominance. Humping should not be allowed, and female dogs can hump just as often as males.

“It tends to be insecure dominant dogs who hump,” Demling adds. “Dogs who are dominant and confident don’t hump. It’s the dogs trying to be cool who hump.”

Demling says humping is “really bad form,” and it’s a behavior that should be stopped by owners to prevent escalating tension.

“It’s the dogs trying to be cool who hump.”

“If your dog humps dogs that don’t care and don’t get corrected, they’re going to keep humping and eventually hump a dog that does care and get into a dog fight,” Demling explains. “To say it’s not okay, it will prevent problems down the road with dogs who care and will fight back.”

4. Why Do Dogs Eat Cat Poop?

This topic sparked a wide range of theories on our discussion boards but unfortunately, there’s no clear-cut answer as to why dogs eat feces. Eating poop is technically known as “coprophagia,” and although there are some logical explanations why rabbits, elephants, gorillas, and even cats eat poop, the reason why dogs choose to chow on poop is unclear.

Although there are no scientific studies backing this explanation, one of the most oft-cited reasons for eating poop is to fill a nutritional deficiency, such as a lack of iron or another vitamin or mineral need.

“Generally dogs are on diets of premium foods that are well-rounded and have all the nutritional elements they need,” California Veterinarian Dr. Deirdre Brandes says. “It’s hard to say for sure but I don’t think that’s the reason why a dog eats feces.”

Another common thought is dogs eat poop when they’re hungry, especially dogs that may be on a strict diet. This third most-common theory suggests this behavior is bred into our pets as common behavior of their wild ancestors.

Cat poop seems to be particularly alluring. Dubbed “kitty caramels” or “kitty rocha,” our canines who do eat poop seem to prefer the feline variety.

“It probably tastes like the food they eat,” California specialty veterinarian Dr. Nicole Eckholm says.

Although there reasons why our dogs eat poop are unclear, one thing is for certain—don’t let him do it! Eating poop poses a host of risks, the most prominent being parasites.

“All kinds of worms are transmitted by eating poop,” Dr. Brandes says. “The most common one we see here in Southern California is called Giardia, which can cause vomiting and diarrhea.”

Eating poop poses a host of risks, the most prominent being parasites.

Since most dogs who have giardia don’t show symptoms or get sick, fecal testing is often done in routine vet check-ups. That’s because parasites can be transmitted to humans! Keep a close eye on your pet and do your best to prevent him from eating poop to help keep your whole family healthy.

5. Why Does My Dog Have Stinky Breath?

A lot of pet parents accept bad breath as a fact of doggy life but dogs with stinky breath have some degree of dental disease and infection in their mouth.

“We have been trained to think some degree of gum disease as being normal—you know, doggy breath is normal—it’s not normal,” veterinary dentist Dr. Brook Niemiec explains. “It’s a sign of infection, and if your dog has bad breath, it’s a sign of severe infection usually needing extractions by that time.”

Dr. Niemiec is one of the world’s leading pet dentists and says dental disease is more widespread than most pet parents think, especially among smaller dogs.

 “We’re finding 90% of dogs have some degree of dental disease at just one year of age,” Dr. Niemiec says. ” Dental disease is far and away the number-one problem diagnosed in small pets today and the smaller the pet, the more common the disease.”

Dental disease starts as gingivitis and shouldn’t be ignored. Early diagnosis and treatment is important to prevent the disease from spreading.

“Some people think, ‘it’s just gingivitis, it’s not a big deal,'” Dr. Niemiec explains. “But gingivitis is a silent killer—it’s slowly killing your dog. We need to get it treated because we would never let it happen in us.”

Gingivitis is reversible but the later stages of dental disease—like periodontal disease—are not.

“Periodontal disease is where you have actual attachment loss and bone loss,” Dr. Niemiec adds. “One the bone is gone, it’s gone—99% of the time, periodontal disease is irreversible.”

The biggest problem leading to infection—and doggy breath—is a lack of oral care. Dr. Niemiec says fewer than one percent of his clients actually brush their dog’s teeth.

“Brush their teeth at home, just like taking care of your own teeth,” Dr. Niemiec suggests.

He recommends small dogs, especially those under ten pounds, get a proper oral exam under anesthesia once a year, and larger dogs be seen once every 3 to 4 years.

“A dental procedure is not just scaling and polishing,” Dr. Niemiec adds. “The most important step is cleaning under the gums and the second-most important part of doing a good oral exam is taking x-rays, which is how we find disease and head off any severe things going on down the line. You can’t do those things without anesthesia and monitoring.”

6. Why Does My Dog Roll in Poop?

No, no, no, no, no! There are few things more disgusting than a dog rolling in poop - or other stinky things. 

Again, there are a few theories as to why our furry friends like to roll around in smelly things but no one accepted truth. The first theory centers around bred instinct based on what their wild ancestors used to do.

“If your dog rolls in a dead animal carcass, it masks their scent so when they are hunting, they don’t let off the predator scent to their prey,” Dr. Brandes says. “Prey will be less aware of the threat and wouldn’t be scared.”

Pyschologist Dr. Stanley Coren wrote about the psychology behind rolling in stinky things on his blog, Canine Corner, and he says this theory makes the most sense.

“The explanation which makes the best evolutionary and adaptive sense is that this stinky behavior might be an attempt at disguising the dog,” Dr. Coren explains.

Dr. Coren offers another explanation: that dogs just like stinky things because it stimulates their dominant sense of smell.

“Dogs, like people, enjoy sensory stimulation and may well be prone to seeking such stimulation to an excessive degree,” Dr. Coren explains.

The Bottom Line

Our dogs do all sorts of gross things that make us pet parents squeamish. Some have legitimate explanations and causes, but others are sort of a mystery. Just make sure you keep an eye out for the things that could put your pet’s health in jeopardy.

By Jacqueline Bennett

November 10, 2015