Fertility Cycle in Dogs

Like all mammals, dogs go through fertility cycles that include heat, gestation, labor and birth. A dog's fertility cycle is very set and only takes place at certain times in the dog's life. The owner who wants to breed a female dog must keep a calendar to know the best times for conception.

  1. Heat Cycle

    • According to the Complete Guide of Responsible Dog Ownership, most female dogs only go into heat twice a year and may skip heats due to stress. These heat periods are the only times when a dog can conceive. Heats last around three weeks and come along every six to nine months. During the first stage of heat, the dog's vulva will be swollen and there will be a bloody discharge. However, it is during the second stage that the dog will actually be fertile. At this point, she will hold herself as if inviting herself to be bred and the discharge will change from pink to a yellow color. This is the point when the dog should be bred.

    Gestation Period

    • The gestation period is the time during which the dog is pregnant. This period becomes obvious as it progresses, with symptoms of pregnancy starting almost immediately. Depending on the breed of the dog, this phase lasts on an average of between 60 and 64 days.

    Symptoms of Pregnancy

    • If a dog is bred during her heat and the breeding is successful, she'll start showing symptoms at the start of her gestation. She may become lethargic and have a diminished appetite, similar to morning sickness. Her nipples will then start to grow, her appetite will return and her abdomen will swell. Toward the end of the gestation period, puppy movement in the abdomen will become obvious.

    Symptoms of Labor

    • Symptoms of impending labor include a dog becoming anxious and clingy, beginning to nest in her whelping box and turning to look at her tail. As labor progresses, her abdomen will begin to spasm and her water will break. Puppies generally will begin to appear with an hour of the dog's water breaking.

    Considerations

    • When you're breeding a dog, it's important to consider the age of the dog. A young dog should not be bred until her first heat has passed; her own growth may be affected by breeding too early. Older dogs have trouble conceiving and may have trouble completing the pregnancy. They may also have trouble during the birth. Always consider your dog's age before you breed her and keep the phone number of a 24-hour veterinarian on hand during the birth in case of emergencies.