Why do wet dogs smell so much worse than dry dogs?

If your dog is bathed every few weeks, they will probably never reach the stage of smelling really bad, and will generally smell (to humans at least) of their shampoo, nothing in particular, or simply mildly of “dog,” that intangible and indescribable scent that everyone recognises!

However, a dog that has not had a bath for some time and/or that is very dirty will tend to smell rather unpleasant, certainly up close-and you may have noticed this if you have ever patted a slightly stinky dog and then found that your hand smells afterwards!

Even bearing all of that in mind, there is one universal factor that most people can agree on-that a wet dog smells significantly worse than a dry dog, however clean or otherwise that dog was to start with!

This can be confusing for many dog owners-after all, if your dog pongs a bit, going out in the rain and rinsing some of the muck out of their skin and coat should surely have the opposite effect. But as anyone who shares their home with a working dog or a dog that loves to get rained on or jump in puddles (like the Springer Spaniel) will tell you, a wet or damp dog can really stink out the whole house!

If you have ever wondered why a wet dog smells so bad, or why your dog smells worse when they are wet than when they are dry, you are not alone-and in this article, we will attempt to answer these questions and more.

Dogs, coats and natural cleanliness

Dogs tend to go for several weeks at a time between baths (or even more in some cases) and they can usually go several weeks after a bath before they will start to smell really funky and have gotten really dirty right down to the skin.

Cats simply don’t need baths because they are so fastidious about their grooming, and spend significant portions of their day licking and tidying up their coats. The tongue of the cat is designed to do this, being covered in little barbs that comb through the coat, going right down to the skin and removing debris so that they don’t build up.

Dogs, on the other hand are not what we think of as being naturally very clean animals-while they do lick their coats, this does little to cleaning it in the same way that a cat does, and if your dog’s breath is not minty fresh, they can also transfer this smell onto their coats too. Additionally, dogs do not lift and part the fur and get down to the skin, so even if the surface of your dog’s coat looks clean, the undercoat and skin are highly unlikely to be!

Wet dog versus dry dog

We all know that a dry dog that hasn’t been bathed for a while can smell, but why does the smell get so much worse when they get wet, rather than getting better?

The answer to this comes from looking at the microorganisms present on your dog’s coat and skin. Bacteria, yeast and so on of a wide range of different types can thrive on the skin and coat of the dog-some of this is systemic to the dog and either harmless or beneficial, such as the bacteria that provides an invisible layer of protection to the dog’s skin. However, your dog can and will pick up all sorts of debris both visible and invisible when out on walks, as well as of course if they are apt to roll in stinky things-and the bacteria from their mouths too gets distributed over the coat when your dog licks themselves.

All of this contributes over time to the visible dirt, grease and shed skin on your dog’s coat and skin, and can lead to their having that unpleasant dirty dog smell that many dogs get between baths!

However, when your dog gets wet, such as if they roll in a puddle or go out in the rain, the smell gets worse-and this is because the water itself reacts with some of these microorganisms, releasing what are known as “volatile organic compounds” and unlocking the funky smell within! Additionally, the heat coming off your dog’s skin leads to a damp, moist environment on their body as they dry off, which further affects the microorganisms present and generates a smell all of its own.

If your dog is drying off inside, the humidity and bad smell that surrounds them will soon spread around the room, to the point that you may be able to smell it in other areas of the house as well!

Once your dog has dried off again, the smell will tend to reduce somewhat, and become more tolerable.

How to avoid that wet dog smell

A dog that is clean and/or that has had a bath recently will not have the chance to have picked up as much of the bacteria and microorganisms that can all lead to the signature smell of wet dog, and so when they do get wet, they will not be as unpleasant to be around as a dog that was dirty to start with.

Bathing your dog every few weeks will of course help to ensure that they do not smell horrendous either when wet or when dry, but over bathing can cause problems of its own too. If you bathe your dog too often or use overly harsh shampoos that strip the skin, it will also remove some of the dog’s good bacteria and skin flora that help to protect it from damage and disease, and other more harmful forms of bacteria.

Additionally, if your dog has bad breath, their coat will soon begin to smell bad too, even if they are recently bathed-so have your vet check out your dog’s teeth and gums if you have any concerns.