6 Signs That Your Dog Is In Heat

A dog cools off in front of an electric fan
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Companion piece to: 6 Signs That Your Cat Is In Heat

A female dog of reproductive age, who has not been spayed, is called a bitch. They will go into "heat" or estrus, seasonally -- in the spring and fall.

The age of the first heat is highly variable - the average age is 6 months of age, but varies from 6 to 12 or more months of age, depending on the individual and the breed/size of the dog. The first heat is earlier for small breeds than large breeds.

Unlike the signs you see when a cat is heat, dogs are typically messier and do not appear to be in "pain" during the heat cycle like cats sometimes do.

6 Signs That Your Dog Is In Heat

  1. Swollen Vulva - This non-painful swelling may noticeable a few days before any discharge or bleeding.
  2. Bleeding - This is usually the first sign noticed. Discharge varies during the cycle, initially bloody to clear or straw-colored. The amount of discharge varies from slight to heavy, depending on the individual, as does the length of time discharge is present.
  3. Mounting behavior - She may try to mount other dogs, objects, or your leg. She may also stand to be mounted by other dogs.
  4. Licking genital area - This may or may not keep the area clean. Some dogs need to wear "diapers" during the heat cycle to prevent soiling bedding, house, etc. Compare prices diapers.
  5. Agitated, nervous, or "nesting" behavior - She may appear more anxious than usual, more clingy, or collect toys and stuffed animals in a sleeping area.
  1. Urinating more often - Frequent urination is a way of marking and letting other dogs know she is in heat.

    Note: If you suspect urinary problems (also indicated by excessive licking of genital area or frequent urination), it is important to see your veterinarian as soon as possible.

The reproductive cycle of dogs

The signs mentioned above are an overview and will vary with each dog and during each phase of the canine estrus cycle.

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If your female dog has not been spayed, it is good to be familiar with these common signs of heat in dogs. Spaying is the best way at this time to prevent pregnancy.