Explanation of Gestation in Dogs

A dog's gestation period usually lasts around nine weeks.
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In all mammals, gestation refers to the time between the conception and birth of babies. For dogs, this period lasts around nine weeks. If your dog becomes pregnant or if you plan on breeding her, understanding her gestation period and the changes it will cause in the expecting mother can help you provide for her needs and be better prepared for the arrival of the new puppies.

Determining Pregnancy

Just as in humans, dogs can visit the doctor to find out if they are pregnant. Several methods of determination are available. The doctor may be able to feel the dog's abdomen to detect the puppies approximately one month after conception. According to Paws and Claws Veterinary Clinic, however, this method is only 85 percent accurate and can be less accurate if your dog is anxious or overweight. X-rays can be used 45 days after mating and are more reliable, but the radiation they produce could potentially harm the embryos. Ultrasounds can also detect unborn puppies, starting at around three weeks after breeding. Another option is a blood test approximately one month after conception to look for elevated levels of the hormone relaxin because its production increases during pregnancy.

First Five Weeks of Gestation

During the first half of your dog's gestation, you will not notice many differences. She may gain weight, and some expectant mothers go through morning sickness. If she vomits occasionally, does not seem interested in food, and seems listless, then she may be experiencing morning sickness. According to WebMD, dogs experience this condition because of progesterone production and uterine stretching. Some veterinarians also recommend adding additional protein, such as eggs or lean meat, to your dog’s diet even during these early weeks of gestation.

Changes During Weeks Six Through Eight

One of the first noticeable changes in expecting dogs is the enlargement of their mammary glands. This enlargement can start just after the fifth week but becomes more obvious around the sixth or seventh week. However, milk production will not begin for another few weeks. She may also gain more weight, especially as she gets closer to the end of the gestation period. This weight increase does not just come from the growing puppies but also because of her increased nutritional needs. After the fifth week, pregnant dogs need to eat twice as much food, usually spaced out throughout the day in smaller meals. A veterinarian can tell you exactly how much to feed your dog daily and can provide suggestions on the best food for her nutritional needs. Although you may assume the expecting mother should be allowed to rest all of the time, regular, non-strenuous exercise is good for her even during the last half of her gestation.

Last Week of Gestation

During the last days of her gestation, your dog's mammary glands may begin to produce a milky substance. This sign indicates that the birth will be occurring soon. Additionally, she may behave differently. With her uterus growing, she will become increasingly uncomfortable, so you may notice her acting more restless than usual. She may also want to spend more time alone. Many expectant moms get ready for the new babies by preparing a "nest," so she may start destroying papers, blankets, or clothing to give her puppies a warm, soft home. Most veterinarians warn parents of young children to keep them away from the soon-to-be mom at this point because she may not be as tolerant as before. Within the 24 hours before she gives birth, the mother dog may start acting extremely anxious and may look for a place where she can be alone for the delivery.