It can happen at any time. While playing with your dog, you get a whiff of something disgusting. “Why does my dog’s butt smell like fish?” you wonder to yourself, thinking back frantically about what you fed your dog recently.

Whether or not you fed fish, you know your dog’s bottom is not supposed to smell like that. You may still be wondering, “Why does my dog’s butt smell like fish?” Meanwhile, they’re licking at their bottom, and you know it’s just a matter of time before your beloved dog starts coming at you for a kiss.

You need an answer now.

Why Does My Dog’s Butt Smell Like Fish?

So if you’re here because you searched, “Why does my dog’s butt smell like fish?” I have an answer!

Your dog most likely has full anal glands.

“What do full anal glands have to do with why does my dog’s butt smell like fish?” you ask. Everything!

Taking a Closer Sniff

To answer the question “Why does my dog’s butt smell like fish?” we need to take an in-depth look at your dog’s anatomy, what anal glands are, and what can happen to them.

What are anal glands?

When you go to the dog park with your pet, chances are you wave or greet your fellow dog owners with a friendly hello. Meanwhile, your dog probably has its nose right up in some other dog’s behind.

While that would be an incredibly awkward and rude way for humans to greet each other, it is perfectly normal for dogs! That is because this is where their anal glands are located.

Like most mammals, dogs have glands in their behind called anal glands. These anal glands, located approximately at 4 and 8 o’clock, are small, pea-sized glands. The glands produce a small amount of fluid dark, smelly liquid.

A small amount of this fluid is naturally expelled when a dog does its business. It acts as sort of an aromatic calling card, leaving essential details about your dog including their sex, age, and health.

What is anal gland disease?

Occasionally, anal glands can develop problems and illnesses. The most common anal gland issue is impacted or blocked anal glands. This happens when the glands become blocked.

When a blockage occurs, the fluid inside the anal gland builds up. That causes discomfort for the dog as the glands become filled with their anal gland fluid. The fluid is also a perfect medium for growing bacteria.

Usually, any bacteria that develops in the anal gland fluid is flushed out when the dog poops. Since a dog with impacted anal glands is unable to expel the liquid, bacteria may build up in the gland, causing an infection.

If left untreated, an infection may progress to the point where the anal gland fills with pus, causing an abscess. If this abscess bursts, the infection can spread and make your dog very sick.

Signs of anal gland problems

As a responsible pet owner, you should always be on alert for any signs that there may be something wrong with your dog’s behind.

Most of the times, humans don’t notice the scent from their dog’s anal glands. (I am sure you will agree that this is a good thing!)

However, if you find yourself asking, “Why does my dog’s butt smell like fish?” that is a good indication that there may be something wrong with their anal glands.

You may notice your dog scooting. When a dog scoots, they set their backside down on the ground and then pull themselves forward with their two front paws. It is kind of cute and funny!

But if you notice your dog doing this a lot, they may be trying to relieve the pressure on their anal glands.

Another sign to watch out for is any swelling or signs up pain around their anal region. If your dog is licking their anus excessively, check for signs of swelling.

And if you see signs of swelling, be alert. If you want a cautionary tale, this Rover article by Amber Christensen can give you the not-so-cute details of what can happen once you notice signs of swelling in the anal gland region.

Not wagging their tail or being reluctant to let you move their tail to check is a sign that there may be something wrong.

Something else to watch for is signs of pain when trying to pass a bowel movement. If your dog is straining more than usual, seems reluctant to go poop, or does not poop, it is time to get them to the vet.

Are there breeds that are more prone to blockages?

Since all dogs have anal glands, it is possible for any dog to have problems with those glands, at any time in their life.

However, smaller dogs like Maltese, Corgi, and Basset Hounds are more likely to have anal gland issues than larger breeds like Labrador Retrievers or German Shepherds.

What causes anal gland problems

Anal gland problems can have a variety of different root causes. Constipation from a poor diet is a contributing factor for many anal gland issues in dogs.

Obese dogs are also at risk for anal gland problems due to poor muscle tone in the anal area. That makes it more difficult for the dog to defecate and effectively empty their anal glands.

What to Do with a Blocked Gland

Now that we’ve answered the question, “Why does my dog’s butt smell like fish,” we now need to address how to solve it.

Anal gland expression

If you take your dog to a professional groomer, anal gland expression is usually part of a typical grooming package. But always ask your groomer first, to make sure.

Your veterinarian’s office is also a good place to get your dog’s anal glands expressed professionally.


If you cannot take your dog to the vet or the groomer, I have good news: you can express your dog’s anal glands at home!

You should only perform this procedure if your dog is not in pain and does not have any visible sores in the area. If in doubt, talk to your veterinarian.

To express your dog’s anal glands at home, you will need a pair of gloves (nitrile or latex work well) as well as absorbent, sterile cotton gauze.

To empty your dog’s anal glands, hold your dog’s tail out of the way. Then feel around your dog’s anus at the 4 and 8 o’clock positions. You should feel the full anal glands.

Holding a piece of cotton gauze over the anus, squeeze inward and upward. This should expel any anal gland fluid that is currently in the glands into the dressing. You may repeat this if you feel like you did not get all

For more detail, check out this video. Fair warning: this is not for the faint of heart!


As they say, an ounce of prevention is worth a pound of cure. (Let’s be honest here: anything that keeps a dog parent from having to empty anal glands is worth its weight in gold, right?)

Luckily, there is an easy way that you can help prevent anal gland issues before they start.

Keeping your dog at a healthy, trim weight will help prevent anal gland problems. Overweight dogs tend to have poor muscle tone, which can contribute to anal gland issues.

Constipation can also contribute to anal gland problems. Including sources of healthy fiber in your dog’s diet can help keep your dog’s digestive system flowing the right way.

When is it a cause for concern?

Anal gland problems are very common. You will not need to fear the dreaded question, “Why does my dog’s butt smell like fish?” once you know what to look for and what to do.

However, there are a few instances where you should consult with your veterinary professional.

If your dog is in pain, has problems defecating, or has swelling on their bottom, you should go directly to the vet.

There is a chance your dog may have an anal gland blockage caused by an infection. In this case, a veterinarian would prescribe a course of treatment as well as address the swelling issues.

Keep an eye out for recurrent anal gland issues. If you notice that you seem to need to express your dog’s anal glands more than once a month, talk to your vet. Recurrent anal gland issues may be indicative of something more involved than your usual anal gland blockage.

Anal gland removal

In severe cases, recurrent blockages may necessitate the removal of the dog’s anal glands. Since domestic dogs no longer need to mark their territory, their anal glands can be removed without adversely affecting their quality of life.

However, as VCA Hospitals notes, the surgery is quite delicate and may result in nerve damage if done incorrectly.

Have you had a dog with anal gland problems? Share your experience in the comments below!