Pregnancy and whelping

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During Pregnancy

What should I feed my pregnant dog?

First 4 weeks of pregnancy

Feed as per normal: you do not want to let your bitch get overweight, as this will compromise her whelping. We recommend high-quality, commercial dry dog food, either a performance or gestational diet that meets all her nutritional requirements. General guidelines include 28-32% protein and 17-20% fat. Do not supplement with pure calcium at any stage of pregnancy. Gradually introduce the performance or gestation food into her diet – do not suddenly change your bitch’s diet.

Last 2-4 weeks of pregnancy

Gradually increase the amount of the performance or gestation food starting about 2-3 weeks before expected due date. Fetal growth is significant after day 42 or so and caloric need will begin to increase during this time. Weight gain should be monitored during this time to ensure appropriate body condition for delivery and lactation. After whelping and during lactation, she will experience significant energy requirements. Multiple small meals are the best way for your bitch to get all her nutritional requirements as her stomach capacity may become reduced with pregnancy, especially if she has a large litter.

During lactation

Feed ad lib during lactation to meet all her energy requirements. Her energy requirements will be highest about 3-4 weeks post whelping. Most require at least two times their normal caloric intake during this time. Starting about 4 weeks post whelping, gradually begin to decrease caloric intake (on a smooth curve), until she is eating her normal number of calories at weaning. Be sure to monitor weight and body condition during this time, as individual requirements vary.

Exercise and Routine During Pregnancy

It is important not to change your bitch’s routine or environment dramatically during pregnancy to avoid significant stress. It is also important she keeps doing what she normally does, especially during the first half of gestation. This is particularly true for exercise, as she needs to remain fit. This will help her to whelp efficiently and without complications. The only recommended change in routine is to avoid taking her to shows, dog trials, or environments where many other dogs from unknown backgrounds will be present. If possible, try and keep her isolated from your other dogs that you take to shows. This will help reduce any chance of exposure to viruses such as herpesvirus, which are easily transmitted by an oronasal route. Herpesvirus is very detrimental to fetal viability if a bitch who was previously not exposed is exposed at any stage of pregnancy.


Intestinal parasites can cause serious problems during pregnancy to both the dam and the offspring. It is generally recommended to deworm the pregnant bitch 10 days prior to expected whelping and every 2-3 weeks while nursing. It is important to use veterinary-only medication that is safe for use during pregnancy and nursing (e.g. fenbendazole, pyrantel pamoate). It is best to refrain from deworming during early stages of pregnancy if possible and not start prior to 40 days of gestation.

Pre-Whelping: Predicting the Onset of Labor

Information on gestational age is crucial for planning clinical assistance during whelping or planning an elective Cesarean section. Accurate gestational age cannot be determined by breeding dates in the canine. If puppies are removed by C-section even 12 to 24 hours too early, they can be premature, and their survival prognosis is significantly reduced. Ways in which we can determine the exact age of the fetuses and when your bitch is due to whelp include:

Ovulation Timing (during breeding)

Progesterone testing and vaginal cytology are the most common methods used to estimate the LH surge and ovulation to accurately determine due dates. LH hormone peak can also be measured; however, daily blood draws are necessary. Whelping generally occurs 63 (+/- 1 day) days post ovulation and 65 (+/- 1 day) days post LH peak. Remember, due to the unique physiology of the canine, breeding dates cannot accurately determine due dates.

Progesterone Drop Prior to Whelping

Serum progesterone levels drop to <2.0 ng/ml 12-24 hours prior to onset of stage one labor. When this occurs, we know it is safe to perform a C-section. However, in bitches with small litters (one or two), the drop in progesterone is inconsistent and must not be solely relied upon.

Temperature Drop Prior to Whelping

The onset of labor can be predicted by taking rectal temperatures twice a day during the week before your bitch is due. Approximately 80% of bitches will have this pre-whelp temperature drop. This drop (usually 2-3˚F lower than baseline and typically to around 97-98˚F) is associated with the drop in progesterone (<2ng/ml) that occurs 12-24 hours before the onset of labor and parturition.

If you can take the temperature at the same time each day, and at the same time in relation to feeding, it will allow you to establish a normal temperature curve for your bitch and accurately detect the “drop.” One-off and random measurements have little predictive value.

How to take rectal temperature:

  • Use a digital thermometer
  • Apply a lubricant (Vaseline) to the tip as to not irritate the rectum
  • Gently insert the thermometer into the rectum placing it against the wall (instead of directly into feces)
  • Hold thermometer in place until it beeps
  • Record results

Abdominal Ultrasound

Early Pregnancy Diagnosis 3-4 weeks after artificial insemination

  • 3-4 weeks after breeding is the most accurate time for pregnancy diagnosis to be determined by an abdominal ultrasound.
  • This is the most accurate time to predict puppy numbers, although not nearly as accurate as confirmation by a radiograph (X-ray) performed a week prior to the expected due date.
  • Measuring the size of the “gestational sac” at this time allows conformation of the whelping date, often within accuracy of 2 days.

Late Pregnancy and “at term” fetal aging and “readiness for birth”

In later pregnancy, measurement of the fetal head diameter becomes more accurate for predicting the whelping date (after 40 days). As the whelping date approaches, changes in puppy organ development help us to determine if the puppies are ready to be born or not. This is very important if a C-section is being considered. Within the last 48 hours, the fetal organs will have completed their development. We can make several measurements and observations at this time that allow us to confirm the puppies are “ready to be born.” For example, the internal structure of the kidney is visible, and the intestinal tract will begin its normal peristaltic movement. We can also measure puppy heart rates at all stages of gestation. This is another parameter that helps us to determine if the puppies are ready to be born or more importantly, are showing any signs of distress. This is especially important when natural whelping is not progressing as expected.

X-Ray Confirmation of Puppy Numbers

A very helpful piece of information before your bitch whelps is to know exactly how many pups she is having. It is harder to determine the number of pups in a litter by ultrasound after Day 40 of pregnancy. By one week prior to the expected whelping due date the puppy skeletons are fully formed. Therefore, the exact number of pups can be confirmed by taking a radiograph. The puppies will not be negatively affected by radiation exposure at this time. There is no anesthetic or sedation required. Your bitch just lies on her side for a few seconds and a quick image is taken. We are then able to count the heads and spines of each of the pups. It is not only good to know when your bitch has finished whelping (especially in the middle of the night) but also to know if she has one or even a few pups left but appears to have stopped progressing with her labor. You are then able to confidently seek veterinary advice more rapidly and reduce pup mortality.

When to seek veterinary attention

Before Whelping

  • Your bitch has reached her due date for whelping without any signs of labor or temperature drop. This is particularly important if she is pregnant with only 1-2 pups (determined by X-ray or ultrasound).
  • Your bitch is unwell, very lethargic, vomiting or not eating anything.
  • Unusual vulvar discharge, especially if it is bloody, green, or black.

During Whelping

  • Green-black vulvar discharge with no puppies born in 15 minutes (at any stage of pregnancy).
  • Profuse bloody vulvar discharge.
  • Active contractions for 20-30 minutes with no puppy born.
  • Weak or intermittent abdominal straining that fails to result in the birth of the first puppy within 2 hours or when the interval between the delivery of two pups is greater than 2 hours.

After Whelping

  • Your bitch is unwell, fever, very lethargic, vomiting or not eating anything.
  • Your bitch has abnormal vulvar discharge.
  • Your bitch is not nursing pups appropriately or exhibiting good maternal behavior.