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How to Tell If a Dog Is in Heat: 9 Signs to Look For

Oliver Jones

By Oliver Jones

beagle on estrus cycle

Deciding to breed your dog is something that you should discuss with your vet. The question of whether to spay or neuter your pet is not always clear-cut. Researchers have identified links between an increased risk of health conditions, such as hip dysplasia and certain cancers. The chances vary with the breed.

The other thing to consider is weight gain. Some dogs become overweight or obese following the surgery due to hormonal changes. It’s safe to say that you should re-evaluate your pet’s diet based on the advice of your veterinarian. On the other hand, pregnancy also poses risks, especially for smaller dogs. You should only breed your female if she’s in tip-top shape.

After all, she must support the lives of the puppies for the approximate 63 days of gestation. If you’ve just bought a female pup and you’re uncertain about her status, several telltale signs can let you know for sure how to take care of your dog for the next few weeks. Here’s how to tell if a dog is in heat (with pictures):

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The 9 Signs Your Dog is in Heat:

1. Behavioral Changes

Often, one of the first things that you’ll notice is your dog is acting strangely. She may seem more agitated or nervous. Your pup may even snap at you. Hormonal changes are driving her behavior. These chemicals can have far-reaching effects. Your once happy-go-lucky pooch may get moodier during this time.

sad french bulldog
Image Credit: Mylene2401, Pixabay

2. Excessive Licking

Another telltale sign of a dog in heat or estrus is if she excessively licks her genital area. Hormones are the culprit, causing changes in your pup’s body, both externally and internally. Some pets are more obsessive about this behavior than others.

3. Vulva Swelling

One physical sign of estrus is vulva swelling. If your dog is long-haired, you may not see it. However, this structure will get noticeable larger and red. That can also explain the excessive licking. The swelling may cause itchiness.

jack russell in heat
Image Credit: Reshetnikov art, Shutterstock

4. Vaginal Discharge

As with humans, a dog will have bloody discharge coming from her vagina. Estrus lasts one to two weeks. You might consider confining your pet during this time to keep your house clean and prevent an unwanted pregnancy. The discharge will eventually clear up and turn watery. That’s when your dog is most fertile.

5. Increased Urination

Your dog may want to go out more often during estrus to urinate. Swelling of your pup’s genitals will put added pressure on her bladder, prompting your pet to go outside more than usual. Once it’s resolved, your dog will return to her regular routine.

dog peeing on floor
Image Credit: komkrit Preechachanwate, Shutterstock

6. Inappropriate Mounting

Canines play-act many events in their lives. That’s essentially the function of play. It applies to mating too. You may find your pet mounting anything she can find. Remember that your pooch is acting instinctively. Don’t scold her for behaving this way.

7. Loss of Appetite

Some pets may feel uncomfortable during this time. That could affect your dog’s diet. For a while, she may ignore the canned food that she usually devours. However, we suggest keeping an eye on your pup for any other symptoms, such as GI distress or lethargy, which may mean that something else is going on instead.

Sleepy sad King Charles
Image credit: Ella_87, Pixabay

8. Tail Position

You may see your dog holding her tail to the side, up, or in other odd positions. Part of the reason is the vulva swelling. It’s also an instinctive behavior to indicate that she’s ready to mate.

9. Flirting Behavior

As your pup gets closer to her fertile time, she may start acting flirtatious with other dogs. She may play and mount other pets, even male dogs. It’s all a part of the courtship ritual. You may also find that your pet gets quite bold in her behavior.

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Final Thoughts

We hope this guide helps you understand how to tell if a dog is in heat! If you choose not to spay your pet, it’s essential to know the telltale signs of estrus. It can help you understand your pup’s change in behavior. It will also alert you to keep a closer watch on your dog. It’s worth mentioning that over 6 million unwanted pets go into shelters annually. We strongly urge you to confine your pooch to avoid adding to these numbers.

Featured Image Credit: Sigma_S, Shutterstock

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