Facts About Dogs in Heat

Cindy SmithDog Health, Senior Dogs

Female dogs are only receptive to mating when they are in heat, and it is also the only time they can get pregnant. A dog’s first heat usually occurs when they are between 6 months to a year old. Here we will separate the facts from the myths about female dogs and their heat cycles.

How long will a heat cycle last?
Between 21 to 28 days.

How often do dogs go in heat?
Most female dogs go into heat every 6 to 12 months. However, this can vary from breed to breed and dog to dog. Small breed dogs may cycle three times per year, while giant breed dogs may only cycle once every 12 months. … It can take up to two years for a female dog to develop regular cycles.

How can you tell if your dog is in heat?

  • Her vulva will look swollen or larger than normal.
  • She will begin to bleed although the amount is very small. Some owners use dog diapers.
  • May urinate more often and tense her rear legs.
  • She may begin “flagging” a male dog, moving her tail to the side and making herself available to a male dog.
  • She may be more clingy to you.
  • She may run away to practice hiding from male dogs.

When is a female dog most fertile?
A female dog is not most fertile right in the beginning. “The fertile period is actually when the bloody discharge starts to subside and it becomes pink or clear and there’s much less of it,” Dr. Kelso says. “Even the swelling of the vulva goes down substantially so a lot of people think the dog is out of heat, but no, that’s actually the prime fertile time.”

How do male dogs react to a female’s heat?
When your dog is in heat, she gives off pheromones which a male dog can smell from miles away. Males may become interested in her and may even fight over her. If you don’t want your dog getting pregnant at this time, keep her away from male dogs.

When should a dog be spayed?
Although there is much controversy on this subject, the best answer is to ask your veterinarian. Many will suggest you spay your dog before her first heat. With February being National Spay/Neuter Month and the number of dogs languishing in shelters, it is important to spay your dog. In females it will decrease the chances of mammary cancer and prevent uterine infections.

What is pyometra?
Pyometra is a uterine infection among unspayed female dogs that can result in death and almost always results in emergency spay surgery. If you notice any pus, or your dog stops eating or drinking, contact your veterinarian immediately.

One interesting note? Dogs do not experience menopause, meaning they remain fertile well into seniority.

It is strongly advised not to breed young female dogs during their first and second cycle. Their eggs are not yet mature and the dog hasn’t reached full maturity.

If you have a male dog with a neighbor female dog in heat, I hope you have a high fence between the two!