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What Does A Dog In Heat Smell Like?

What Does A Dog In Heat Smell Like?

As part of the natural canine reproduction process, female dogs go on heat twice a year.

If you are a first-time dog owner with a female dog that hasn’t yet been spayed, the period will fascinate you to the core.

No matter how guarded your dog is, male dogs will hang around your home looking for a chance to mate with the ready female.

But how did they know she was in heat in the first place?

They smelled her scent, of course. Trust a dog to pick up scents from up to three miles away.

That only means one thing; a female dog in heat releases a smell.

What is the smell like? We’ll find out shortly.

Heat Cycles in Dogs

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To best understand the process of “being in heat“, you need to know how the canine reproductive system works.

Typically, at the age of six months, a female dog reaches the child-bearing age.

Some arrive there pretty early—as early as three and half months and others at about 10 months of age.

So, if you are not ready to have puppies around your house, don’t wait until 6 months to have your female dog spayed as is the popular belief. You might just be too late.

As soon as your doggie is ready, she will go into her first heat cycle. The first stage is called proestrus and it is when the dog’s body prepares for mating.

You will notice her licking her vulva repeatedly, being clingy, rubbing her genitals on surfaces, and releasing a discharge with some blood spots on it. Her vulva will start to swell at this time.

Next, she will go into actual heat, or estrus. Here, she will be open to mating.

During this stage, her hormones are over the roof. She will urinate frequently as a way of marking spots to tell the males that she is receptive to them.

Her vaginal discharge will take on a pink color. She will also raise her tail as she moves around.

Diestrus follows next and this is basically the stage after the heat cycle.

Whether the dog mates or not, she will go into diestrus where the body either develops into pregnancy or goes back to normal.

The anestrus is the last phase. Here, the female dog has no signs of sexual behavior whatsoever.

Odor and Heat

When a female dog is in heat, particularly during the estrus stage, her body is going through all sorts of hormonal changes.

Naturally, she will release odors because of the high surge of hormones. Canines are designed this way to ensure the continuity of the species.

The odors come from the discharge leaving her body.

Essentially, during the proestrus stage, your fur baby will release a mucous-like discharge with bloody stains.

You will come across the discharge in her bed or play areas. Some dogs don’t have bloody discharges, though.

As she enters estrus, the discharge will look like straw. It is this specific one that gives off a distinct smell that male dogs love so much.

Granted, the smell may not appear strong to you but male dogs can sniff it even when they are far away, thanks to their remarkable sense of smell. This is the way canines were designed to reproduce.

The odor is what alerts male dogs of fertile females that require their services.

Considering that female dogs are only receptive to heat-related male attention during the estrus cycle, the odor helps the male dogs in detecting when ovulation has occurred and the female is absolutely ready or ripe for conception.

How Is The Smell Like?

Different dog owners interpret the smell of a dog on heat differently—depending on one’s olfactory sensitivity and the intensity of the dog’s heat odor.  

There are those that say their female dogs give off an unpleasant and strong odor that makes them undesirable.

Then there are those that insist the odor is very mild.

Others barely catch a whiff despite the colossal amounts of discharge throughout the house.

Generally, many have described the smell to be fishy and pungent.

Caution: The Pungent/Fishy Smell May Be Due To Other Causes Other Than Heat

While the unpleasant, pungent, or fishy smell may be a natural side effect of your dog’s estrus cycle, it can also be caused by underlying health conditions, including:

I. Anal Glands

Anal glands are basically small anal sacs on each side of your dog’s anus.

They produce certain doggy aromas that our canine friends use to mark their territories.

These glands get squeezed when dogs poop, releasing small amounts of their content (fluids) to coat dog poop.

Sometimes anal glands don’t get squeezed well, especially when the dog’s poop is too hard or soft.

This may cause the fluids to build up over time, leading to infections and a fishy smell.

You may also want to check: Why Does My Dog Still Smell After Her Glands Have Been Expressed?

II. Pyometra

This is a serious infection of the uterus of a female dog. According to Webmd, it occurs as a result of hormonal changes in the dog’s reproductive tract, which in turn, fills the uterus with pus.

III. Metritis

This is an inflammation of the uterus lining due to bacterial infection. It usually occurs within a week after your dog has given birth.

IV. Vaginitis

This is a medical term for inflammation or swelling of a dog’s vagina or vestibule. It may cause redness, discharge, and a fishy smell.

V. Skin Infection

Skin infections may also cause your female dog to smell bad.

Common causes of skin infections in dogs include yeast and bacterial infections, skin irritations, and allergies.

VI. Bad Breath

The pungent or fishy smell that you are noticing when your dog is in heat could also be due to bad breath.

Common causes of bad breath in dogs include oral infections, periodontal diseases, swollen gums, kidney disease, tumors, and diabetes among others.

It is critical to consider every potential problem that may be causing your dog to smell during heat (or any stage in life for that matter) as some issues can be serious and even life-threatening if not diagnosed and treated in time.

Related: Why Does My Dog’s Vag Smell Like Metal?

How to Get Rid Of Dog Heat Smell

Smelly estrus discharge can be a major turn-off for many dog owners. No one enjoys having their entire house reek of estrus odor for some days.

Plus, if you are not ready to be breeder, the presence of ten or more male dogs hanging around your compound will drive you up the wall.

Lucky for you, there are a few things you can do to mask the smell. These include the following:

I. Bathe The Dog’s Hindquarters

Your dog releases the discharge from her rear. The first defense mechanism against the smell would be to keep her hindquarters as clean as possible.

What better way than to clean the area more frequently than normal?

Grab your shampoo and get cleaning at least twice a day.

While you are at it, make sure that there are no male dogs around when you take her to the bathroom.

A lot can happen in the twinkling of an eye.

II. Use Diapers

A dog on heat leaves discharge everywhere—on the floor, sofa, dog bed, clothes, you name it.

Not only does this worsen the smell but the blood on the discharge can stain your surfaces.

A diaper will help trap any discharge from the dog’s body. That way, your house will stay clean and odor-free.

Plus, there’s a high likelihood that male dogs will not catch the scent of the discharge from the diaper.

III. Apply a Menthol Rub on Your Dog’s Tail

This is an ingenious trick of masking the smell and warding off male dogs from mating with your dog.

See, menthol rubs like the Vicks Vapor Rub bear a strong minty odor that is more powerful than the actual odor coming from your dog. It is also unpleasant compared to the estrus scent.

Even if a male dog approaches your doggie, he will be repulsed by it before he mates with the queen.

Related: How to Make Menthol Spray for Dogs

IV. Utilize Bleach

One of the most potent deodorizers, bleach gets rid of odors in a flash.

When your dog is on heat, you can mask the smell by spraying a solution of bleach and water where your dog has pooped or urinated. 


Besides the smell of a dog in heat concerns, we also bump into a lot of questions related to dog heat cycle from time to time.

We are not going to try to answer all of them in this post but here are quick answers to the most common ones:

How Often Do Dogs Go Into Heat?

On average, female dogs experience a heat cycle twice annually—about after every 6 months.

However, the interval may vary depending on a dog’s breed…

For instance, smaller dog breeds may experience up to three heat cycles per year while their giant breed counterparts may only get one cycle in a year.

It is also important to note that the cycle frequency may be somewhat irregular for young dogs that are beginning to cycle.

It can take up to around 2 years for such dogs to experience regular heat cycles.

How Long Does A Dog In Heat Smell?

On average, a heat cycle in dogs lasts between 2 and 4 weeks—depending on your dog.

So, if your dog is producing an unpleasant heat scent, this is basically how long you should expect the smell to last.

But this depends on your dog—the duration can be shorter or longer.

Again, there is a possibility of catching a whiff of the scent later—when the 2-4 weeks duration is elapsing.

In other words, you may detect the smell of a dog’s heat scent for a shorter duration than the indicated 2-4 weeks.

It is only male dogs that have the capacity to detect heat smell from the onset of the cycle to its end!

Considering that dogs are biologically equipped with the innate need to reproduce, they have hypersensitive nasal passages that are capable of sensing whenever a heat cycle is about to happen.

That’s why it is not uncommon to see male dogs going crazy for a female before you observe common heat signs like swelling of the vulva or vaginal discharge.

Irrespective of the duration that the heat scent lasts, you should be able to tell that the cycle is over (and probably that the smell may have other underlying causes) when your dog’s vulva returns to its normal size and there is no more vaginal discharge.   

Related: How Long Does A Dog In Heat Bleed?

Parting Thoughts

A dog on heat can give off a distinct pungent and fishy smell, thanks to her estrus discharge.

If you are like most people, the smell will drive you insane.

Your male dog will go crazy for it but you, on the other side, will find it unpleasant.

Fortunately, you have quite a number of options when it comes to masking it.

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