Whether you are planning to breed your dog or are concerned your dog may be pregnant, you may want to get acquainted with the gestation period in dogs. The gestation period is considered to be the time frame between ovulation and birth. Many dog owners consider the gestation period to be the time frame between the actual mating and birth. This causes many owners to grow concerned when they notice that their dog’s pregnancy is not within what is considered the normal gestation period. To better understand the canine gestation period, it’s important to learn more about some basics of dog reproduction.
About Dog Fertilization
When a dog is in heat, a variety of hormonal changes take place. The word “estrus” is used to depict the period of time when the female dog is receptive to the male. The estrus phase is estimated to last an average of 9 days, but may last anywhere between 3 and 21 days, explains Arliss Paddock. During this time, the previously blood-tinged discharge turns into a straw colored discharge. Estrogen levels fall, progesterone levels rise and the pituitary gland starts releasing a surge of luteinizing hormones which trigger the release of eggs two days later, a process known as “ovulation”.
Despite the fact that there are high chances for pregnancy to occur, when mating takes place, there are ultimately no guarantees for successful fertilization. Fertilization occurs when the male dog’s sperm fuses with the female dog’s eggs in the uterine tubes. This occurs in the ampulla of the uterine tube. Because the egg is not ready to be fertilized immediately when ovulation takes place, optimal breeding should take place two days after ovulation, which is 4 days after the day when the progesterone levels rise, explains Margaret V. Root Kustritz, a veterinarian specializing in small animal reproduction.
The average gestation period in dogs is estimated to be around 9 weeks, which is about 63 days. However, as mentioned, things get a bit confusing depending from which day you start to count. The gestation period is pretty consistent when counted from the date of ovulation to the actual date of birth. Because it’s challenging figuring out when a dog exactly ovulates, it may difficult to calculate the gestation period accurately. Fortunately, there are tests that help predict when mother dog ovulates by testing her progesterone levels.
When the gestation period in dogs is counted from the actual day of mating, things get challenging. First off, if a dog mates multiple times, the owner may not know which mating day should be used to start counting. Should you count from the first mating or the last mating? This can cause great variances of even 2 weeks, according to P.W Concannon.
On top of that, consider that a dog’s sperm can live 10 to 11 days once inside the uterine tubes. This means that should the female dog be bred 10 days before her eggs can be fertilized, her gestation period may appear to be 70 days long! If on the other hand, she is bred right on the day her eggs can be fertilized, it will appear to be as short as 60 days long!
Signs of Problems
While 63 days is the average gestation period in dogs, dogs can give birth normally anywhere between 57 and 65 days according to VCA Animal Hospital. However, if birth takes place too early such as around 56 days counting from ovulation day, there are high chances the pups will be premature and not fully developed. On the other hand, if the dog is pregnant over 65 days counting from ovulation day, a vet should be consulted so to rule out complications.