You lean down to cuddle your dog after a long day, expecting that familiar warm, slightly earthy scent that every pet parent knows by heart. Instead, you’re hit with something unexpected. A strong, fishy odor that seems to come out of nowhere. It’s confusing, a little alarming, and definitely not pleasant.
Before you panic, it helps to know that a fishy smell in dogs is actually a common issue. While it might seem mysterious, there is usually a clear explanation behind it. Understanding the possible causes can help you respond quickly, protect your dog’s health, and restore freshness to your home.
Why Does My Dog Smell Like Fish
Every dog has a natural scent, but a noticeable fishy odor often points to a specific physical cause. In most cases, the reason is related to small scent glands located near your dog’s rear end.
These glands, commonly called anal glands or anal sacs, are part of a dog’s normal anatomy. When everything functions properly, you should never notice them. But when something disrupts that balance, the odor can become obvious.
The Role of Anal Glands in Dogs
Dogs have two small sacs positioned on either side of the rectum. These sacs produce a strong-smelling fluid that acts as a communication tool between dogs. It carries scent markers that provide information about identity and territory.
Normally, the glands empty naturally during bowel movements. The pressure created when passing stool helps release a small amount of fluid. However, if the glands do not empty completely, the fluid can build up.
When that happens, the material inside thickens and may become difficult to release. This buildup is what typically causes the strong fishy smell many owners notice.
Signs of Anal Gland Problems
If your dog smells like fish, you may also observe behavioral changes. Common signs include:
Scooting across the floor
Excessive licking or biting near the rear
Straining during bowel movements
Visible redness or swelling near the anus
A sudden, strong odor after moments of stress or excitement
While scooting can look amusing, it often signals discomfort. If left untreated, impacted glands can become inflamed or infected, leading to more serious complications that require veterinary care.
Other Possible Causes of a Fishy Smell
Although anal glands are the most common source, they are not the only reason your dog may smell like fish. Several other health issues can contribute to unusual odors.
Urinary Tract Infections
In female dogs especially, urinary tract infections can cause urine to develop a strong or fishy smell. Additional signs may include frequent urination, accidents indoors, or straining.
Vaginal Infections or Reproductive Conditions
Female dogs can develop infections that create noticeable odors. These conditions often require prompt veterinary evaluation to prevent complications.
Dental Problems
A fishy smell may also come from your dog’s mouth. Infected teeth or gum disease can create unpleasant breath. Tartar buildup, drooling, and difficulty chewing are signs that dental care may be needed.
Skin and Yeast Infections
Yeast overgrowth on the skin can produce a distinct odor sometimes described as fishy or similar to corn chips. This commonly occurs in moist areas like paws, skin folds, or the genital region. Redness, itching, and hair thinning may accompany the smell.
Which Dog Breeds Are More Prone to Anal Gland Issues
Research from the VetCompass program at the Royal Veterinary College analyzed veterinary records from more than 100,000 dogs to determine breed risk factors. The study found that certain breeds are more prone to anal sac disorders compared to mixed breeds.
Breeds with higher risk include:
Cavalier King Charles Spaniels
King Charles Spaniels
Shih Tzus
Bichon Frises
Cocker Spaniels
Small breeds in general appear more susceptible. Body structure, stool consistency, and genetic predisposition may all contribute.
Why Anal Glands Fail to Empty Properly
Several factors can interfere with natural gland expression.
Low-fiber diets may lead to softer stools that do not provide enough pressure to empty the sacs. Obesity can also reduce muscle tone in the area, affecting proper release.
Chronic allergies may contribute as well. Dogs with skin allergies sometimes develop inflammation around the gland openings, making drainage more difficult.
Stress and anxiety can occasionally cause sudden gland release, which explains why some dogs emit a strong odor during frightening situations.
What You Should Do If Your Dog Smells Like Fish
If the odor persists, scheduling a veterinary visit is the best course of action. A veterinarian can examine your dog, determine the cause, and manually express the glands if necessary.
Early treatment prevents discomfort and more complex health concerns.
Professional Evaluation
A vet can identify whether the issue is simple impaction or something more serious. They may prescribe medication if infection is present.
Regular Anal Gland Care
Some dogs, especially small breeds, may need routine gland expression. This can be done by a veterinarian or trained groomer. However, overexpressing glands without need can cause irritation, so professional guidance is important.
Improve Diet and Fiber Intake
High-quality, fiber-rich diets help produce firm stools, which naturally assist in emptying the glands. Some veterinarians recommend fiber supplements or probiotics for recurring issues.
Dental Hygiene
If the smell originates from the mouth, regular brushing, dental chews, and professional cleanings can dramatically reduce odor.
Skin Care Management
For yeast or bacterial infections, medicated shampoos or topical treatments may be recommended. Keeping skin folds clean and dry helps prevent recurrence.
Preventing Future Odor Problems
Prevention begins with overall health management. Maintaining a healthy weight supports proper muscle tone and digestion. A balanced diet rich in nutrients promotes regular bowel movements.
Regular exercise also plays a role. Movement stimulates healthy digestion and helps maintain muscle strength.
Fresh water should always be available to support urinary health and digestion.
Routine veterinary checkups ensure that minor concerns are addressed before they become larger problems.
When to Seek Immediate Veterinary Advice
While many causes of fishy odor are manageable, certain signs require prompt medical attention.
Seek veterinary care if you notice:
Persistent swelling near the rear
Discharge that appears abnormal
Severe discomfort when sitting or defecating
Sudden lethargy combined with odor
Difficulty urinating
Early intervention leads to faster recovery and less stress for your pet.
The Science Behind Odor Production
Odors are created when bacteria break down proteins and fats in bodily secretions. In anal glands, natural bacterial processes contribute to the strong scent of the fluid. When material accumulates, bacterial growth increases, intensifying the smell.
Similarly, oral bacteria cause bad breath when plaque builds up on teeth. Yeast produces characteristic odors when it multiplies on warm, moist skin.
Understanding the biological basis of these smells helps remove the mystery and highlights why hygiene and proper care matter.
A Balanced Perspective on Dog Odor
It is important to remember that a mild scent is normal for dogs. They are active animals who explore the world with enthusiasm. However, sudden changes in odor often signal something worth investigating.
Rather than masking the smell with sprays or perfumes, identifying the root cause ensures your dog remains comfortable and healthy.
Most anal gland issues are easily treatable. With appropriate care, the fishy smell usually disappears quickly once the underlying problem is addressed.
Final Thoughts
A fishy smell coming from your dog might be unpleasant, but it is rarely mysterious once you understand the possible causes. From anal glands to dental hygiene and skin health, several manageable factors could be responsible.
Dogs rely on us to notice subtle changes in their behavior and health. Paying attention to scent is one way we can respond to their needs.
Curiosity has always guided humans in caring for animals. When we ask why something smells different, we are really asking how we can help. By staying observant and proactive, we ensure our companions stay healthy, comfortable, and ready for the next tail-wagging adventure.
Sources
American Kennel Club. Anal Gland Disorders in Dogs.
Royal Veterinary College VetCompass Programme. Breed predisposition to anal sac disease in dogs.
American Veterinary Medical Association. Dental Care Guidelines for Dogs.
Merck Veterinary Manual. Urinary Tract Infections and Yeast Dermatitis in Dogs.