Ask a Vet

Why Does My Dog’s Butt Smell Like Fish?

By Kerry
Updated on

Something that you will have to deal with on a regular basis when you own a dog is the wide variety of odors that do not always have a simple explanation. Everyone is familiar with the common smells that a dog produces or develops when they have rolled in something that they shouldn’t have, but why does your dog’s but smell like fish?

This is one of the most unpleasant smells that can occur, and if this has happened to your dog, you are probably wondering if there is something wrong with them. If this is a smell that you have noticed, then you probably want to get to the bottom of it to make this awful odor go away.

If you are currently in this situation, we are going to tell you exactly why this is occurring in this article, so you can understand exactly what is going on. This will help you to find the right solution to your problem, so you can get rid of that fishy smell.

Why does my dogs but smell like fish

Why Does My Dog’s But Smell Like Fish?

Some of the reasons that can explain why your dog’s but smells like fish are that they have an anal gland infection, impaction, or blockage.

The anal glands can be found on either side of your dog’s but, and they contain sweat glands that can produce this fishy smell. This acts as a scent marker for dogs, and this smell can even occur when your dog is scared. 

What Does it Mean if My Dog’s But Smells Like Fish?

If your dog’s but smells like fish, then it is likely that they have a problem with their anal glands, which is going to need attention. If your dog has an infection, then it can lead their but to smell like fish.

You should also look out for any swelling or discoloration, or for anything that looks different than normal.

What Are Anal Glands?

Anal glands are also called anal sacs, and they are basically small sacs that can be found on either side of your dog’s anus. These sacs are full of sweat glands, and these glands will produce an unpleasant secretion that acts as a scent marker for your dog. 

When your dog poops, these secretions will then be passed on to the feces, which will provide other dogs with important information about your dog. This is the main reason why your dog might seem interested in other dog’s poop when you are out on a walk. It also explains why dogs sniff each other’s buts when they meet. 

When your dog is scared, they can also express their anal glands, and this is a normal occurrence. If this happens, it is likely that you will notice a distinct and fishy smell.If you notice that your dog smells like fish often, then there is probably something happening with their anal glands.

Why Do Anal Glands Cause a Fishy Smell for Dogs?

The anal glands are located in the anus, and they actually contain a liquid that is responsible for strong a fishy-smelling odors. This liquid can vary in color and appearance, depending on the type of dog, and it can be thick and gray for some dogs, or yellow or thin in other dogs. 

Ever single dog will have anal glands, and most of the time, the will work as they should without causing any problems. They will help to mark a dog’s territory whenever they poop, as the liquid that is within the anal glands will be released when a dog relieves themselves.

Although, there are times when these glands can become blocked, which means that due to something that is happening to your dog, these glands are not being emptied properly. This can go on to cause further complications in the future, which is why it is an issue that needs to be dealt with as soon as possible.

Unfortunately, there is no exact reasons why your dog is experiencing anal gland issues, as there are so many things that could lead to such a problem. However, there are many experts that would argue that the problem is linked to other health conditions that are commonly found in dogs, like obesity, allergies, chronic diarrhea, and gastrointestinal disorders.

You should always be on alert if your dog suffers from any of these conditions, and you start to notice a fishy smell. We will explain more about the different anal gland issues that can occur below.

What Are the Signs of Anal Gland Impaction?

As you now know, the anal glands that your dog has will naturally empty themselves when your dog goes to the toilet. However, this process can go wrong at times if something has been impacted or is not working as it should. This can lead to the fluid not being emptied from the glands entirely. If this happens on a regular basis, it can lead to the fluid becoming almost dry, which results in impaction.

A dog that is suffering from this condition will unfortunately be in a lot of pain, but spotting the symptoms of this condition is relatively easy. The first and most obvious symptom is a fish smell that is coming from their but. This will be a strong and pungent smell, and is the main symptom of the condition. 

You might also notice that your dog drags or scoots their but across the ground, sometimes multiple times a day. Another symptom of this condition is excessive licking or nibbling at the but, which can even lead it to become red and sore.

Some of the other symptoms that you can look out for are suddenly sitting down, looking at their back end for long periods, and yelping in pain when they take a poop. If you notice that any of these things are happening, then you should contact a vet straight away for more advice.

What is the Treatment for Impacted Anal Glands?

Sometimes, the treatment for impacted anal glands is that your dog will need to have their anal glands expressed manually by a vet. This should get rid of the fishy smell and help to relieve your dog of their pain. 

Smaller dog breeds might need to have their anal glands expressed on a regular basis, and this is something that can be done by a vet or a groomer. As well as this, you can learn how to do it yourself if you have the stomach for it.

Compacted anal sacs will need the assistance of a vet, as these are carefully expressed. Your vet may also need to use a softening agent or saline rinse for compactions that are particularly dry. Once the compacted material has been removed, you may need to feed your dog a diet with higher amounts of fiber in it, as this will help them to be able to express their anal glands naturally. 

If the anal sacs are infected or abscessed, they will need to be cleaned with an antiseptic, and they will usually be treated with antibiotics. You might also find that your vet recommends holding a hot compress to the area if an abscess is suspected. 

Sometimes the anal glands may need to be removed, and this is typically the case if your dog develops anal sac disease or if they have anal sac tumors. These will usually be removed with surgery, and there can be some complications with this treatment method. However, most of these procedures are successful, and they will not negatively impact the quality of life that your dog has.

What Are the Signs of Anal Gland Infections or Abscesses?

Anal gland infections and abscesses are also something that you should be on the lookout for if you notice a fishy smell. If an infection is severe, it can lead to an abscess, which is a collection of pus that will be really painful for your dog to experience. If you think that your dog has an anal gland infection or abscess, you should seek professional advice from a vet immediately. 

Some of the symptoms that are present in anal gland infections or abscesses are similar to those that are present in impaction. These can include nibbling or licking at the anus, dragging their bum across the floor, crying out when pooping, and more.

Although, dogs that are suffering from this issue will usually also have wounds, blood, discharge, and matted fur around their bums. Your dog might also have a change in mood, become lethargic, eat less than normal, and become irritable around other pets and owners.

How to Prevent Anal Sac Disease

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Anal sac disease is not always possible to prevent, but there are some things that you can do to help, like:

  • Make sure that you are feeding your dog an appropriate diet with sufficient fiber
  • Keep an eye on your dog’s poop to make sure that everything is as it should be
  • Exercise your dog on a regular basis to make sure that they are an ideal weight
  • Provide your dog with plenty of clean and fresh water

What is an Anal Sac Tumor?

Anal sac tumors are really serious, and they are quite uncommon for dogs to experience. However, it is still important to be aware of this condition, so you can make sure that this is not the problem. They will have the same effect as other conditions that are associated with anal glands, which cause them to stop working as they should. 

However, anal sac tumors are known for quickly spreading to other tissues in the body. They are also more life-threatening than other anal conditions. It is thought that around 25% of cases of anal sac tumors can lead to hypercalcemia, which is a highly dangerous condition that can lead to kidney failure.

Why Does My Dog’s Breath Smell Like Fish?

If you have noticed a fishy odor that is coming from your dog’s mouth, then it is possible that they have a problem. Some of the things that can be associated with this are kidney disease, diabetes, or periodontal disease.

You should always make sure to brush your dog’s teeth around 2 or 3 times a week to prevent a build up of plaque and help to get rid of bad breath. You can also use dental treats that scrape off plaque and tartar as these will naturally clean your dog’s teeth.

If your dog has a fishy smell coming from their mouth, it could be:

  • Gingivitis
  • Tartar, plaque, and calculus
  • Stomach upset
  • Food caught in the teeth
  • Tumors, decaying teeth, tooth root abscess or infection

How Do I Stop My Dog From Smelling Like Fish?

When you notice that your dog has a fishy smell around the but, you should book them in to see a vet as soon as you can. Most of the time, your dog will need to have their anal glands emptied. This is typically a quick and painless procedure, and your dog will be in and out of the vet in no time if this is the case.

Once they have completed this procedure, their but will no longer smell like fish. However, some dogs, particularly smaller breeds, may need to have their anal glands expressed a few times a year. So, this fishy smell can come back and indicate that they need to have this procedure again.

It is possible for you to learn how to do this yourself at home, and you can ask your vet about it if this is something that you would like to do. You should always contact your vet before trying to do this yourself as you don’t want to do it wrong. Without the right knowledge and experience, you could cause further issues, like inflammation or permanent scarring.


More often than not, a fishy smell is simply a sign of impacted anal glands, and this is something that can be solved quite easily.

However, there are some instances where this problem could be much more serious, and it is important to be aware of other conditions that could be the problem.


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About the author


Kerry White is an avid dog lover and writer, knowing all there is to know about our furry friends. Kerry has been writing for PetDT for three years now, wanting to use her knowledge for good and share everything she can with new dog owners.Kerry has two dogs herself - a German shepherd called Banjo and a chocolate labrador called Buttons. Kerry knows more than anyone how adjusting to new life with a puppy can turn your life upside down, and she wants to ease some of the burdens through her articles.