Breeding & Reproduction - Animal Care Center of Castle Pines

Breeding & Reproduction


The reproductive cycle in female dogs has 4 phases. Female dogs who have not been spayed typically have 2 periods of heat per year, each lasting 2 to 3 weeks. The first heat typically occurs between 6 and 15 months of age depending on the size of the dog. Females can become pregnant during their first heat and any later heat period. Male dogs do not have a reproductive cycle. They respond to females in heat at any time of year. Pregnancy in dogs lasts about 63 days, but they can give birth as early as the eighth week of the pregnancy. Signs of pregnancy include a swollen abdomen that at later stages of the pregnancy may sway beneath her, weight gain, and swollen teats that may release milk when squeezed. The dog will also begin nesting, so it is important to have a comfortable and well-padded box prepared for her. Start getting her used to sleeping there before the puppies come, and make sure it is in a secluded area.


Cats also have a heat cycle. A female cat can enter her first heat at as young as four months of age, and she generally will have 2-3 heat cycles during the breeding season, which is normally February to October in the northern hemisphere. Pregnancy in cats lasts about two months, with an average litter size of about four kittens. Signs of pregnancy include a swollen abdomen, increased appetite, and swollen mammary glands that may release milk when squeezed. During the later stages of pregnancy, the cat will seek out a nesting area and place bedding in a quiet, secluded area. If breeding is your goal with your pets, we here at the Animal Care Center are available to help you through every stage of the pregnancy to ensure that the puppies or kittens are born healthy and safe, and that your pet is also happy, healthy, and safe throughout the process.