Pets don’t always smell particularly aromatic. Curious dogs and cats can certainly get into smelly situations.
But sometimes a bad smell is a sign of something more serious. If you can rule out external factors — like wallowing in something foul-smelling — and a bad smell lingers, it may be time to seek professional help.
“Your dog and cat probably have their ‘normal’ smell,” says Dr. Heather Berst, veterinarian and medical director at animal health company Zoetis. “If you notice a change in your pet’s odor, don’t try to mask it with a shampoo or spray. It may mean your pet has a medical problem. Check with your vet to make sure it’s not a medical issue.”
Berst and other experts shared with the HuffPost some common disorders that manifest in changes in smell and which smells to look out for.
A musty or “stinky” foot odor can indicate a skin fungal infection
“Skin infections often change the way a dog or cat smells,” says Berst. “The smell can be associated with itching, redness, hair loss or a change in coat texture.”
Malassezia dermatitis is a yeast infection of the skin that is fairly common in dogs and can also occur in cats.
“Yeast usually smells musty or smelly feet,” says Dr. Sarah Wooten, veterinary expert at Pumpkin Pet Insurance.
Chronic skin fungal infections are accompanied by a number of other symptoms. Be alert to unusual odors, irritated skin, or behaviors that indicate skin disorders. Pets with underlying allergies can also be more prone to skin infections.
A sweet or foul smell can be a sign of a bacterial skin infection or an abscess
“Staph infections on the skin may have no odor or may smell sweet,” says Wooten.
She notes that bacterial skin infections are usually associated with redness, hair loss, bumps that resemble pimples, flaky skin, and oozing from skin folds.
“Skin that smells like corn chips has an infection with Pseudomonas bacteria,” adds Wooten. “This skin is also just red and itchy. This is more serious than “frito feet,” a commonly searched term that’s considered normal in dogs.”
Bacteria can also cause skin abscesses — pockets of pus on the body that can be very painful and produce a distinct odor.
“Abscesses smell awful, putrid,” says Wooten. “You’ll never forget the smell! Abscesses are usually associated with localized skin swelling, redness, pain, inflammation and possible pus formation.”
A putrid or yeasty odor could indicate an ear infection
Yeast or bacterial infections can also occur in a pet’s ears. Ears that fold over often trap moisture, creating environments for yeast or bacteria to thrive.
“Ear infections often have an unpleasant odor,” notes Berst. “Depending on what’s causing the infection in the ear, you may have different smells, including a yeasty smell or a very bad smell.”
The smell will likely be stronger if you lift the animal’s ears, and there may be some discharge and redness. As with skin fungal infections, yeast ears smell musty or like smelly feet. They could produce a dark brown discharge.
“Ears infected with bacteria can smell sweet or foul, or if they have a Pseudomonas infection, they smell like tortilla chips and have white discharge,” says Wooten.
She adds that ear mites, which are fairly common in cats, can also cause an odor.
“Ear mites cause black deposits in the ears, as well as redness and severe itching,” says Wooten. “They smell like either yeast or bacterial ear infections.”
Bad breath can be a sign of dental problems
“Halitosis is a very common cause of a foul-smelling dog,” says Dr. Dana Wilhite, a consulting veterinarian at Full Moon Pet, a pet food company. “Dental disease is usually the most likely cause, as foul-smelling bacteria in the mouth create a smell similar to a sewer. Excessive drooling due to rotten, aching teeth can also cause the skin around the mouth to become infected, increasing the foul odor.”
Gingivitis, bleeding mouth tumors, or a nasal infection can also cause an odor, so get it checked out by a veterinarian. Even if there is no underlying medical problem, professional counseling can help with the problem.
“Living with a ‘lazy mouth’ dog isn’t fun for anyone involved, and you’ll be amazed at the difference a dental cleaning from your vet can make,” says Wilhite.
She found that bad breath is a very common olfactory complaint in cats.
“Although cats tend to groom themselves well, they cannot brush their teeth on their own. And if they live long enough and haven’t received routine dental care, they will end up with dental problems,” says Wilhite.
Breath that smells fruity could indicate diabetes
Aside from a dental infection, changes in a pet’s breath odor can be a sign of complications from diabetes that require medical attention.
“A dog or cat with uncontrolled diabetes can have very sweet and fruity-smelling breath,” says Wooten. “These dogs and cats also usually have weight loss, drink a lot, and pee a lot.”
Wilhite points out that stomatitis, gastrointestinal disease, and respiratory infections can also cause foul breath.
A fishy smell could be a result of anal gland problems
“Dogs and cats have two anal glands at the 3 and 7 o’clock positions of their anus,” says Wooten. “Normally there is no smell coming out of these glands. However, dogs and cats can express their anal glands when they are frightened, which can result in a strong, fishy, musty odor that lingers even after you and your pet have been cleaned.”
Although it can be normal for a pet to express their anal glands occasionally, be on the lookout if the strong odor is frequent. This could be a sign that something is wrong.
“If these glands become infected and an abscess develops, the odor can be intensified,” says Wilhite. “If your dog is slipping, acting uncomfortable, has swelling, is leaking blood or fluid from this area, he will appreciate a visit to the vet.”
Vets and zookeepers can express your pet’s anal glands if they become too full.
Excessive gas can be caused by diet.
“Excess gasoline is a smell that’s hard to miss,” says Wilhite. “This may be diet-related and related to the type and amount of fiber in the diet. Certain ingredients may work better than others for some dogs and cats in terms of gas production.”
Bloating can be a sign that it’s time to change your pet’s diet. But if it persists even after a switch, you should consult a veterinarian for advice.
“Non-dietary causes of bloating are usually related to how much air a dog is swallowing, but can sometimes be a sign of gastrointestinal disease,” says Wilhite. “Your veterinarian can advise on how to fix your dog’s excess bloating.”
A strong smell of urine could indicate a problem with the urinary system.
Dogs and cats can also develop urinary tract infections, which can manifest as changes in smell.
“A strong urine odor could be a sign of a UTI, especially if it is accompanied by other signs of UTI such as increased urination [to urinate] or bloody urine,” says Wooten.
Watch out for other problems in the urinary system, such as B. Kidney failure, which can cause an odor similar to urine.
“Cats with severe kidney disease smell like ammonia and act very ill—not eating, lethargic,” notes Wooten.
A smell of rotting meat could mean parvovirus.
New pet owners are on high alert for parvovirus, which can also have smell-related symptoms.
“Parvovirus is a highly contagious, often fatal viral disease that causes severe vomiting and diarrhea, usually associated with a lower GI [gastrointestinal] bleed,” says Wooten. “The smell of Parvo is terrible and can blow your mind. The dog and poop smell like rotting meat and may have a metallic rim due to the iron in the bloody poop.”
Abnormal odor could be a care issue.
“Poor care can result in an unusual smell,” says Wilhite.
She added that when cats are unable to groom themselves properly, it could be the result of an underlying medical condition such as obesity, arthritis, diabetes, an overactive thyroid or cancer.
“Cats that are unwell for any reason, including arthritis, groom less and have a musty, greasy coat that is sometimes matted,” says Wooten. “They can collect feces around their rear end – ‘Dingleberries’ – which smell and look like feces.”