Dogs are cute and wonderful animals to have as pets. Sometimes, they have traits or behaviours just like humans; one of them is having an awful smell of a fish.

Dogs can smell offensive for several reasons, and the way a dog smells could differ. One of the bad smells dogs sometimes have is that of a fish.

Unlike us humans who are conscious of how we smell and take deliberate actions to ensure we smell good, dogs don’t seem to mind if they smell like a fish, unusual or lousy. They even don’t mind digging through trash and enjoy doing this a lot.

It is normal for dogs to be smelly around their anus, paws and ears, just like us humans smell more around armpits and pubic regions.

Dogs smell around their paws, ears and feet because of the presence of specialized glands that produce oils. Dogs could also smell because of the presence of yeast or bacteria because of underlying health issues around these areas.  

Your dog smelling unusual without you being able to figure out why is something you should visit the vet over and have checked out, as it could be an underlying health issue that is making your dog smell.

Why does your dog smell like a fish?

A dog smelling fishy is usually one of the most off-putting smells for dogs to have and is sadly a fairly common smell.

If you recently started adding fish to your dog’s diet or your dog’s diet smells fishy, includes fish supplements or fish oil, then you have no reason to worry, as reducing or getting rid of the diet would help your dog smell normal again.

But if this isn’t the case, your dog might be suffering from a very common underlying health issue called anal sac disease, as fishy smells in dogs are usually due to secretions from a dog’s anal glands.

Does my dog have anal sac disease?

There are various reasons your dog might smell fishy: fishy breath, fishy urine or vaginitis in female dogs, as there are other infections that could make a female dog smell fishy.

Also, if your dog suddenly smells fishy for a short while, it is most likely because it is frightened, as your dog can have sudden anal gland secretions due to fear.

Paying attention to your dog faeces is a good way to know if your dog has anal sac disease. In this article, we’ve listed other symptoms to check and behaviours your dog might exhibit if it has anal sac disease.

What is anal sac disease in dogs?

Dogs have a pair of fluid structures inside their anus that secretes fishy, foul-smelling liquid that ranges from thin and yellowish to thick and greyish in appearance.

These anal sacs help secretes some oils when your dog defecates or is frightened. Anal sac disease is an umbrella term used to describe problems with a dog’s anus. Sometimes a dog’s anal sac does not secrete enough oil or is completely empty of fluid, causing the fluid to dry, make the glands solid and impacted.

When an anal sac has been impacted, it can no longer secret oil, making it very painful for a dog to poop or touch. Over time, if anal sacs that have been impacted are not treated, they may become abscessed and rupture.

A dog’s anal sac may become impacted for various reasons. Sometimes a dog’s stool might be too soft and not strong enough to press the anal sacs in order to secrete oils when the dog defecates, or there might be something unusual about a dog’s anal sac.

A dog’s anal sacs can also get infected. If a dog’s anal sac is infected and not treated in time, it can also become abscessed. Infected and abscessed anal sacs can be very painful.

image of why is my dog smelling like a fish

Sometimes the area around the anal sacs may appear discoloured or swollen. Due to how painful an infected or abscessed anal sac is, your dog might require pain medication or antibiotics. If an infected or abscessed anal sac is left untreated, it could rupture through a dog’s skin. 

There is also the possibility a dog smells fishy because of an anal sac. Anal sacs tumours make the anal sacs feel firm and enlarged, making it difficult or impossible for a dog to express its anal glands. 

While the exact reasons dogs have issues with their anal gland aren’t known fully, some dogs stand a higher chance of having problems. Dogs that suffer from obesity, chronic diarrhoea, constipation and environmental or food allergies have a higher chance of getting anal sac disease. 

Signs of anal sac disease in your dog

It is extremely important to pay attention to your dog’s stool if you suspect or want to check if your dog has anal sac disease. Besides your dog having a fishy smell, there are other symptoms that would let you know if there is a problem with their anal glands.

These other symptoms include; your dog scooting on the floor, blood in its faeces, the area around their anus being discoloured or swollen, your dog biting or licking its anus and finding it difficult with obvious discomfort when it is defecating.

The discomfort while defecating could hurt so much your dog makes noises as it struggles to defecate. Another sign you should check out includes checking your dog’s rectum for hard lumps. 

Your dog licking its anus or scooting might seem normal, but you should take it as a warning sign of anal sac disease. 

Dogs prone to anal sac disease

Some dog breeds are more likely to have anal sac disease. Anal sac disease is more common in small breed dogs than in giant breed dogs. Also, dogs that are obese have a higher chance of having problems with their anal sacs.

Older dogs are more likely to deal with constipation because of dehydration. When stools are too soft or too hard, these dogs anal sacs don’t release their oils or release too little.

How to prevent anal sac disease

It is pretty difficult to stop your dog from having problems with its anal sac, but there are a few things you can do to prevent it from happening. Being conscious of your dog’s weight, giving it a diet that contains the right amount of fibre your dog needs and exercising your dog regularly would help your dog a lot.

Also, ensure your dog has lots of clean water to drink to help it stay hydrated. You should pay attention to your dog’s faeces, checking for blood or your dog having difficulty defecating.

Anal sac issues can be treated easily, so getting rid of the fishy smell from your dog and helping it smell normal again would not be a problem once your dog has been treated.

Should I visit my vet?

If you suspect your dog has anal sac disease or it smells fishy along with other symptoms, ensure you visit your vet immediately. Don’t relive your dog’s anal sac by yourself, except if your vet has shown you how to go about it. Once you get to the vet, a rectal exam or ultrasound would be carried out on your dog.

Your vet might also express your dog’s anal glands if he considers it necessary.

Some veterinarians believe that the external expression usually done by groomers and overexpression could be harmful to a dog’s anal sacs, causing more health complications in the future.

If your dog isn’t showing any symptoms of anal sac diseases, it should not be expressed regularly. 

If your dog’s anal sacs have developed an infection or tumour, your vet will most likely carry out a biopsy before prescribing a treatment method for your dog.

If your dog has anal sac disease, your vet might ask you to help your dog lose weight by reducing its diet or having your dog exercise regularly.

Your vet might also suggest giving your dog a high fibre diet or a hypoallergenic diet. Drugs and supplements that control environmental allergies may help ease the irritation caused by anal sac disease.

You could ask your vet for a prescription and would get one if your dog needs it. In rare cases where your dog’s anal sac disease can not be treated by any of these methods, your dog would require surgery.


Your dog smelling bad can be an indicator of its health. Your dog smelling bad or having an odour doesn’t mean it smells fishy. If your dog smells unusually suddenly, contact your vet and schedule a visit, as it could be an underlying health issue.

Contacting and visiting your vet could help you get reassured your dog is not in any danger and get professional advice on how to help your dog get rid of whatever lousy smell your dog has and how your dog can smell nice.

Article Sources

Pristen Pets uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
1. American Kennel Club: Real reasons dog smell like fish
2. Great Pet Care: Why does my dog smell like fish
3. BetterPet: Why does your dog smell like fish

Write A Comment