Reproduction Basics: Dog Pregnancy & Birth
You've bred your bitch. But how do you know if she's pregnant? Human pregnancy tests don't work on dogs because the human tests detect the presence of human chorionic gonadatropin (HCG), which dogs don't produce. One problem with using other hormone tests for bitches is that both pregnant and nonpregnant bitches experience increased progesterone levels following estrus---the phenomenon that's responsible for false pregnancies. Although progesterone is higher in pregnant than nonpregnant bitches, there's enough overlap to make testing meaningless.
Pregnant bitches do, however, produce one hormone that nonpregnant bitches don't: relaxin. Relaxin is produced when the fertilized egg is implanted, and remains in the blood throughout pregnancy. It can takes about 21 to 25 days following fertilization for the egg to implant and produce detectable levels of relaxin in the blood, so for best results wait about 28 days post-breeding to test.
Traditionally, breeders have relied on palpation, in which a veterinarian carefully feels the bitch's abdomen for the developing puppies. Palpation is most successful between days 28 to 35 post-ovulation. The developing puppies have the consistency of a hard-boiled egg and, depending on the size of the dog, may range from grape- to egg-sized. They have distinct spaces between them, enabling them to be counted with a small degree of accuracy. After day 35 days post-ovulation, the developing pups have grown so large and are surrounded by so much fluid that there's no longer a distinct space between them, so they feel like one long tube and are impossible to count.
By 24 days post-ovulation, you may want to try ultrasound, which is not only a reliable way to confirm pregnancy, but a fair way to get a rough idea of the number of puppies. The more puppies there are, the less accurate the count is, because the spaces between puppies are compressed and it's difficult to see all the puppies at once.
The puppies' bones become visible on radiographs by about day 50 post-ovulation. At this time an experienced veterinarian can count the number of puppies, see if any are abnormally large or positioned abnormally, and even detect any that may be dead. This knowledge helps plan the whelping, for example knowing whether a Caesarean section might be needed, or knowing when the bitch has whelped the last puppy. Note, however, that in large litters the count may be off because the jumble of skeletal images can become confused.
Some non-technical signs of pregnancy include nausea around 18 days post-breeding, enlarged pink nipples after about three weeks post-breeding, and a clear mucous discharge also after that time. Enlargement of the mammary glands may begin as early as the 35th day of pregnancy, but more often don't do so until around the 45th day. A couple of days before delivery they will usually begin producing milk. Unfortunately, bitches in false pregnancies also have enlarged, milk-producing glands.
As the pregnancy progresses, she may start to gain weight after the fifth week of pregnancy, with abdominal enlargement in the last three weeks---especially if she has a large litter. But this can also happen with pyometra, a potentially dangerous infection of the uterus that is more likely to appear around this same time. Of course, if you can see puppies moving in there, kicking against the walls of the abdomen, that's a good sign she's pregnant, not sick. This usually occurs in the last week or so before whelping.
Dog gestation is approximately 63 days after the date of the first mating, but can vary depending on when she actually ovulated. If a pregnancy seems to go on past the due date, progesterone levels can give some information about whether dystocia, or difficulty whelping, may be the problem. In many breeds a planned Caesarean section is far safer than allowing the bitch to whelp naturally, especially if there is a chance of dystocia that may then require an unplanned Caesarean section.
Feed her as you normally would until her fifth week of pregnancy, at which time you can begin to add puppy food to the mix. Increase the proportion of puppy food until she is eating pure puppy food by her last week. Do not add supplements, especially calcium. Talk to your veterinarian before giving her drugs or parasite treatments.
Begin taking the expectant mother’s temperature morning and evening every day starting about a week before the due date. When her temperature drops dramatically, to around 98 degrees F (or 37 degrees C) and stays there, you can anticipate pups within the next 12 hours. She will become increasingly restless and uncomfortable; eventually she will begin to strain with contractions. The puppies are preceded by a water bag; once this has burst, the first puppy should be born soon. If a puppy appears stuck, you can use a washcloth and gently pull it downward along with her contractions. Never pull a puppy by a limb, tail, or its head, though. You may wish to help the mother clear the pup’s face so it can breathe, and you may wish to tie off the umbilical cord. Do this by tying dental floss around the cord about 0.75 inch from the pup, and then cutting the cord on the side away from the pup. Make sure that for every pup that comes out, a placenta comes out, too. Allow the dam to eat one placenta if she wants, as they contain important hormones, but they contribute to diarrhea and one is enough.
You may have a whelping emergency if:
- More than 24 hours have passed since her temperature dropped without the onset of contractions.
- More than two hours of intermittent contractions have passed without progressing to hard, forceful contractions.
- More than 30 minutes have passed of strong contractions without producing a puppy.
- More than 15 minutes have passed since part of a puppy protruded through the vulva and the puppy makes no progress.
- Large amounts of blood are passed during whelping
When in doubt, call your veterinarian.