Puppies are exciting. However, any experienced breeder will tell you they’re also a lot of work. A responsible breeder prepares long in advance—to identify the purpose of the breeding; to carefully plan and research the breed, the standard, the health history, and available healthy males of good temperament; to form partnerships with their veterinarians and build relationships with breed mentors—in order to have the best chance of producing beautiful, healthy puppies of great temperament and maintain the health of the dam.
Whether you are new to breeding or awaiting the birth of a reserved puppy from a breeder’s litter, the wait can seem eternal. Thank goodness, a bitch’s cycle and the gestation period in dogs is much shorter than in humans.
Hormones Drive Estrous
“A female dog enters puberty when she begins the estrous cycle by having her first season (a.k.a. heat),” explains Dr. Katherine Hollinger, veterinarian and breeder of Lagotti Romagnoli. Timing can vary, but most dogs begin coming into season between 6-to-18 months of age. A bitch can become pregnant as early as this first cycle, however, there is a lot a responsible breeder should do before breeding a dog:
- Complete health testing pertinent to the breed
- Consider showing or titling the dog in conformation or other activities and sports to compare them to other members of their breed
- Select a suitable healthy male of excellent temperament for breeding
- Prepare a safe, nurturing environment for mother and pups
Hormonally driven estrous cycles recur every 6-to-12 months throughout the life of the dog, varying depending upon the dog, environmental factors, nutrition, age, and breed. There are also some breeds that may go into heat only once a year, such as the Tibetan Mastiff and the Basenji.
“Successfully achieving a pregnancy involves correctly timing ovulation during estrus and breeding within a specific timeframe, depending upon the type of semen and mode of insemination that will be used to produce a litter (i.e., live cover, artificial insemination using fresh, fresh chilled or frozen sperm). This requires working closely with your reproductive veterinarian to pinpoint the ovulation date with progesterone tests or by using an intact male to gauge his interest in mating and the receptivity of the female,” says Dr. Hollinger.
Dog Reproductive Cycles Are Unique
The dog has a unique cycle among mammals, explains Dr. Hollinger. Upon ovulation, the eggs are not fully mature. They must divide, which can take 24-to-72 hours post-ovulation, before they are fully mature and can be fertilized by sperm. Healthy sperm, on the other hand, can fertilize a mature egg and can live 5–11 days in the reproductive tract of a female.
“Understanding the estrous cycle plays an important role in determining when to seek care, when to schedule testing and pregnancy examinations, and when to prepare for delivery of a litter. The ovulation date or best estimate of the ovulation date is often used to determine the best time to breed a bitch,” she says.
Proestrus
Proestrus lasts 6-to-11 days and is the first stage of the reproductive cycle when estrogen levels increase. Females start to attract males, although they are likely to reject their advances until estrus. The signs of proestrus are swelling of the vulva, bloody discharge, and standing or mounting behavior with other dogs. However, Dr. Fran Smith, DVM, a board-certified theriogenologist (a specialty dedicated to animal reproduction) and AKC Breeder of Merit, points out that the timescales for both the proestrus and estrus stages are highly variable— both can range from 3 to 21 days.
Estrus
Estrus is the time when the female is receptive to breeding, usually lasting 5-to-9 days but may vary between 10-to-20 days. A surge in luteinizing hormone (LH) occurs that triggers ovulation with concomitant decrease in estrogen and increasing progesterone levels. These hormonal changes are what influence the female’s receptivity to breeding. The signs of estrus are a soft and enlarged vulva and vaginal discharge that may become straw-colored, although many color variations exist between individual dogs.
Diestrus
Diestrus is characterized by the elevation of progesterone. Progesterone peaks 2–3 weeks after ovulation and plateaus for 1–2 weeks before slowly decreasing over 10–30 days. Progesterone, the pregnancy maintenance hormone, increases throughout this post-estrus stage whether a dog is pregnant or not. Diestrus ends when the dam delivers a litter or progesterone concentrations return to baseline. During diestrus, the bitch’s discharge tapers; she no longer permits mating; and the vulva slowly returns to normal.
Anestrus
Anestrus is the name of the timeframe between one heat cycle and the next. During this period, the uterus repairs and returns to a period of normal inactivity. This generally takes 4 months but is variable and can last as long as 6-to-12 months.
How to Tell if a Dog Is Pregnant
“Hopefully, a breeder has been working with the veterinarian to pinpoint the ovulation date for a successful breeding. The ovulation date or LH surge are the best predictors of the due date. The ovulation date is also critically important for scheduling pregnancy exams. These exams may include palpation or ultrasound to confirm a pregnancy or radiographs to identify the number of puppies performed after [around] day 55 of gestation. While there may be commercial pregnancy tests for dogs, these do not help with identifying important milestone dates such as ovulation date, best insemination date, pregnancy stage, or due date,” says Dr. Hollinger. A vet may also perform a relaxin test, a blood test which can be useful in evaluation if a bitch is pregnant at the time of the test, performed approximately 27–30 days after breeding.
Another test that may be helpful, according to Dr. Hollinger is a nomograph, a blood titer performed on the bitch to identify distemper and parvo antibodies to gauge the level of antibodies that will be transferred to the puppies in colostrum. This allows a breeder to plan a puppy vaccination protocol when maternal-derived immunity has adequately waned.
What Are the Stages of Gestation?
The normal gestation period in dogs is approximately 63 days as measured from ovulation, although this can vary slightly by several days. Calculation of a litter due date varies depending upon what parameter is used to begin counting, for example the due date is:
- 65–66 days from LH surge (day 0) and 63 days on average from ovulation (2 days after LH surge)
- 64–66 days from the initial significant rise in progesterone, or
- 58–72 days from the first time the bitch allowed breeding
Calculations of due dates based upon a breeding date have a wider range since the bitch may have bred several days prior to the LH surge and ovulation.
“Pregnancy in dogs is relatively short compared to humans, about 9 weeks total, and each day matters. Knowing the due date is important for the health of the pregnant bitch and the puppies and is used by the breeder to adapt changing nutritional demands and schedule veterinary care during pregnancy,” reports Dr. Hollinger.
Timeframe of Canine Pregnancy
Every canine pregnancy is unique, but here is the timeline of the reproductive cycle for dogs:
Weeks One to Four
A canine egg, once ovulated, will mature within 24-to-72 hours. The mature egg is viable and can be fertilized for up to 2-to-3 days after maturation. Spermatozoa present in the uterine horns may be capable of fertilization for 5-to-11 days. A fertilized egg takes from 18 to 23 days to implant in the dam’s uterus.
“Many dogs don’t show any symptoms during the first three weeks of their pregnancy. The fetus begins to take shape by day 22, and by day 28 or 30 a veterinarian using ultrasound can see signs of pregnancy in the dam’s uterus and may be able to detect fetal heartbeats. Around day 20-28 the embryos may be identified using gentle abdominal palpation,” Dr. Hollinger says.
Some symptoms to watch for during the first month are:
- “Pinking up” having enlarged and pink tipped nipples
- More affectionate behavior
- Decreased physical activity
- “Morning sickness” occurring post implantation
Weeks Five to Eight
Fetal development moves quickly during the second month. Eyelids form by day 32 and toes are visible by day 35. The nails form by day 40, and the coat and skeleton follow a few days later (day 45). By day 55, an X-ray can reveal the number of puppies in the litter, and a bitch may start looking for a place to nest around day 58 to 62.
Signs of pregnancy in the bitch are much more obvious during the second month:
- Noticeably increased appetite
- Weight gain
- Increased urination
- Behavioral changes
- Clear, odorless vaginal discharge
- Enlarged, firm abdomen (days 45 to 50)
- Decreased appetite (day 45)
- Visible puppy movement in abdomen (day 50)
Week Nine
The bitch is ready to whelp at nine weeks. Puppy development is almost complete around day 58, which means the puppies will begin to move into whelping position in the birth canal over the last few days of the bitch’s pregnancy.
Symptoms include:
- Waist may trim as puppies move into the birth canal
- Appetite loss around day 61 or 62
- Drop in body temperature 12-to-24 hours before labor
- Restless and extreme nesting behavior
- Pacing, panting, shivering, or digging
Stages of Labor in Dogs
Since you want your dog to be as comfortable and relaxed as possible during labor, she should be in a familiar, warm, dark, quiet area that’s not accessible to other household pets. You’ll also want to have a veterinarian you trust on call in case there are complications or dystocia. “At this point, the onset of labor is controlled by a complex interplay of hormones,” Dr. Hollinger says.
Stage One
The first stage lasts 12-to-24 hours and is often not outwardly noticeable. Contractions in the muscular wall of the uterus increase throughout stage one, both in strength and frequency, and the cervix dilates. You may observe:
- Change in disposition and behavior including restlessness, nesting, and desire to be alone
- Refusal to eat
- Vomiting
- Panting
- Clear vaginal discharge
Stage Two
Puppies are delivered during stage two. The birth of each puppy is close when you see a sac protrude from the bitch’s vulva. This stage can take anywhere from 1-to-24 hours, and bitches deliver one puppy at a time. Each delivery should not last more than 1-to-2 hours and normally occurs every 30-to-60 minutes. Pups may safely present head-first or tail-first. If there’s a green discharge, the placenta may have separated and the puppy must immediately be delivered. Knowing the total number of expected puppies will allow you to recognize when the bitch is finished with stage two.
Stage Three
The placenta is delivered in stage three. Stage two and stage three occur simultaneously, and stage three is complete when all placentas are delivered. You should contact your veterinarian if your dog’s labor takes more than 24 hours, or if more than 2 hours pass in between puppies. Dogs may deliver two fetuses at a time and then deliver two placentas because they may come from two uterine horns.
Signs of Dystocia
Dystocia, or difficulty during birth, can occur due to many factors affecting the bitch or the puppy. The most common cause in dogs is called uterine inertia, which can be inherited, age-related, or result from nutritional imbalance, disease, or an obstruction in the birth canal. Other causes of dystocia include stress, pain, abnormal position of the fetus, abnormally long gestation or whelping periods. There are situations when a Cesarean-section may be called for.
Canine dystocia is estimated to occur in less than 5% of deliveries, although research found it may be considerably higher in certain breeds such as the Chihuahua, Pug, Boston Terrier, and French Bulldog. It’s critical for all breeders to discuss the signs and causes of dystocia with their veterinarian and to call for veterinary help immediately if it’s needed. An experienced breeder will have made an action plan with their veterinarian in advance of the due date for getting the bitch care should she have difficulty in delivering.
Caring for Your Dog After Delivery
After your dog gives birth, you’ll want to monitor her temperature, vaginal discharge, mammary glands, and milk supply. “Sanitation, including frequent handwashing and maintenance of a clean whelping box are important during the early life of the puppies to reduce risk of infection for puppies and dam,” says Dr. Hollinger.
You may observe the following changes following whelping:
- A discharge called lochia, varying in color from green to red or brown lasting from 3-to-8 weeks. If the lochia has a foul odor or increases in flow, it could be a sign of infection and requires veterinary attention.
- Some dogs may suffer from inflammation/infection of the breasts called mastitis or of the uterus, called metritis, may occur. It’s a good idea to monitor the dam’s mammary glands for heat, redness, or hard nodules and if noted to take her temperature and contact your veterinarian.
- It’s rare for a dog not to produce enough milk for the puppies (agalactia) but can occur if there are underlying conditions. Making adequate fluids available by offering water and supplementation with calcium and calcium-rich foods postpartum will help.
- The mother dog may experience heavy shedding of her coat while nursing. This is temporary.
- At first, she may be reluctant to leave the pups, requiring you to bring nutritious food and fresh water to her.
- For the first few days after whelping, stools may be soft
- The nursing bitch is under physical and emotional stress and may become easily annoyed and even aggressive, most commonly 2-to-3 weeks after whelping.
As time goes on, even the most dedicated mother will be ready for short breaks from her pups. Allow her to get some exercise and alone time. All parents deserve a break. The puppies will grow quickly. Good breeders, the pups’ first teacher, realize they have much to learn during the first 8-to-10 weeks. Soon they’ll be ready for their new families and forever homes.