Canine Heat Cycle

canine heat cycle




Canine heat cycle...


Read all our information on spotting any illness symptoms that maybe very early signs of pregnancy, advice on your dogs gestation period, pregnancy calendar and a guide to spotting symptoms of a false pregnancy.

Take your time a read all the information for when your dog's in season...

Canine Heat Cycle
  • The heat cycle in dogs refers to the period when the female or bitch is in season where she is ready to mate or breed. The cycle is more technically known as the estrus.
  • The canine heat cycle normally occurs from the age of 6 - 12 months.
  • In larger breeds dogs can be in season much older, sometimes when they are 12 - 24 months old.
  • The heat cycle will normally last for about 3 weeks or 21 days. 
  • Although this lasts about 3 weeks they are only capable of breeding or getting pregnant for about 3 - 21 days in the entire 3 week period.
  • An interesting fact is that dogs will carry on having periods for their entire lives, which is of course different for humans who stop having periods at a certain age.
Symptoms of Pregnancy in Dogs
  • Your beloved little dog is now an adult and will start to lick and pay more attention to her vulvar.
  • Your dog's vagina may also be swollen.
  • It is very common for your dog to bleed from her vagina, the flow of bleeding maybe heavy or slow, but the amount of bleeding will decrease as the month goes on.
  • At the beginning of the cycle the blood will often be a dark red color but as the season progresses it will become more of a salmon color.
  • Although the vagina will appear swollen at the beginning it will begin to become softer later in the month, this is due to the progesterone levels rising which prepares her ovaries for the release of her eggs.
  • You may see your dog start to curl her up tail on either the right or left side and she may even urinate more often as she wants to spread her scent to the males.
Stages During the Canine Heat Cycle

Stage 1 - The first stage is known as the proestrus stage where your dog will urinate more, have swelling around the vulvur. Although male dogs will want to mate

Stage 2 - The second stage is known as the estrus. This is the stage where your dog will allow a male to mate with her, this can happen from anywhere from 3 - 21 days.

Stage 3 - The third stage of the cycle is known as diestrus where she is beginning to come out of season. At this point she will not be so keen to mate. This stage can also last for different amounts of time varying from 4 - 14 days.

The next canine heat cycle will start from about seven months from the last time she was in season.

Canine False Pregnancy


The cause of canine false pregnancy is due to a misunderstanding in the hormonal changes. An increase in prolactin and decreases in progesterone are a common cause canine false pregnancy.

A dog that is suffering from a false pregnancy may show some of the following symptoms...
  • She may start to nest.
  • Your dog may also start to mother obejcts around the House.
  • She may start lactating.
  • Believe it or not she may even look like she is going into labour.
  • Your dog may also suffer from abdominal distension.

Canine Pregnancy Calender


  • If you want to be accurate when using a canine pregnancy calendar, you need to know when your dog mated.
  • After about 24 - 48 hours the eggs will be fertilized in the oviducts.
  • After about 10 - 11 days the eggs will become what is known as blastocytes. The blastocytes will then develop into embryos. 
  • Your dogs nipples will start to become pink and enlarged after about 15 days.
  • After the pregnancy has reached 20 days your dog's fur on the stomach will become thinner.
  • From days 21 to 28 your dog mat develop morning sickness just like us humans.
  • After one month in the canine pregnancy calendar it is important that you feed your dog appropriately. A smaller meal is much better than a big meal during the pregnancy calendar. She will also spend more time grooming and her nipples will also be sore.
  • Six weeks into the pregnancy calendar your dog may completely lose her appetite and her abdomen will be really large.
  • Two months into the pregnancy calender your dog's nipples will ooze milk when squeezed. Your dog's rectal temperature drop from approximately 101 degrees to about 98 degrees.
  • After about 12 hours from this point the little puppies will be delivered.
We hope you found our guide to the canine heat cycle easy to read and informative.




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