A pre-breeding veterinary exam is important in establishing baseline data and to plan for the care of the dog during pregnancy. All bitches should be current on required vaccinations, heartworm tested negative, and dewormed with a broad spectrum anthelmintic (dewormer).  Older bitches should have blood work completed, including a complete blood count, serum biochemistry profile, and a urinalysis to evaluate the dog’s general health status. 

 

Brucella canis testing and, if desired, canine herpes virus titers can be performed.  B. canis is a bacterial agent which causes abortion in the dog.  Canine herpes is a fatal viral infection of puppies from 1 – 3 weeks of age.  The veterinarian will need to submit a sample of blood serum to a diagnostic lab for this testing. 

 

Pregnancy is then diagnosed by palpation or ultrasonography. The bitch’s body condition is again assessed and her appetite & diet evaluated.  Changes in her activity can be discussed during this appointment and the need for isolation in later pregnancy stressed.  A final prenatal vet evaluation can be done at 10 – 14 days prior to delivery.  Abdominal radiography can help determine puppy count.  Ultrasonography can be performed to assess health of the fetuses and monitor fetal heart rate.  Digital vaginal examination can be performed on any bitch that had a previously diagnosed vaginal stricture, as some do relax as parturition (delivery) approaches. 

 

The veterinarian should evaluate the dog’s packed cell volume (test for anemia), serum glucose, and serum calcium levels at this time.  This is an excellent time to discuss indications of dystocia (birthing problems) with the breeder and to instruct the breeder to monitor the bitch’s body temperature twice daily to help predict the onset of labor.  Success has been seen in monitoring uterine activity in late-term bitches to better determine the arrival and normalcy of labor.

The diagnosis of pregnancy may begin with abdominal palpation and then be more accurately diagnosed with radiography (x-rays) and ultrasonography.  Abdominal palpation for pregnancy is best performed between 21 and 28 days of gestation, when the fetuses can be felt like small “golf balls”. 

 

Ultrasonography can identify fetuses as early as 17 days of gestation.  More reliable identification of gestational sacs (fetal vesicles) is obtained at 25 – 30 days from the last breeding.  Fetal movement and heartbeats can be seen at 28 days gestation.  The presence of intestinal gas can interfere with observation of the fetal sacs. 

 

Radiography can identify fetal skeletons at 43 – 45 days of gestation.  Because potential disparity between days from breeding and gestational age may exist, lateral (side) and ventrodorsal (belly) views at or after 50 days from the last breeding is recommended to prevent false negative results. The bitch should be radiographed with an empty stomach and colon to enhance the ability to observe all pups present.  Radiography is relatively insensitive to identifying fetal distress, as fetuses must be dead for at least 24 hours before radiographic signs are present. 

 

Obese bitches should undergo weight reduction before breeding to improve conception rate and decrease the risks of dystocia and poor lactation (milk production).  Pregnancy is never a good time to attempt weight loss. 

 

During the first 3 weeks of gestation, the well-conditioned bitch may undergo little or no weight gain.  The consumption of a high quality adult dog food is sufficient unless the dog is underweight.  Bitches that enter pregnancy excessively thin should eat a growth or performance food to rapidly correct their condition.

 

At about 3 weeks gestation, many bitches experience a loss of appetite that persists for about a week.  Nausea and mild vomiting occasionally accompany the anorexia.  Appetite will return at about week 4.

 

 Occasionally, bitches have poor appetites throughout pregnancy.  During the last half of pregnancy, energy requirements increase, as does the need for protein and carbohydrates.  This is usually provided by increased intake of a feed for growth, pregnancy, and lactation.  Too rapid alteration of diet may lead to bloat, gastrointestinal distress, or diarrhea. 

 

The amount of food required by a pregnant dog in later gestation increases in proportion with litter size and growth.  A 40% average increase in food consumption accompanies the 20 – 55% increase in body weight.  Because of increased intra-abdominal pressure from the enlarging uterus, multiple small meals are easier for the bitch to consume. 

 

Bitches carrying large litters may have abdominal discomfort the last week of gestation and experience a decrease in appetite.  Many, but not all, bitches will stop eating 24 – 48 hours before delivery.

 

The administration of supplemental vitamins, minerals, and supplements to pregnant bitches is discouraged.  Calcium supplementation must be avoided.  Although calcium requirements increase in the pregnant bitch, they are met by the increased amount of food ingested.  Excess calcium above the amount provided by a high quality diet suppresses parathyroid hormone production and increases the bitch’s risk of puerperal hypocalcemia. Puerperal hypocalcemia is an acute, life-threatening condition that usually occurs 2-4 weeks after whelping.  It results from the loss of calcium into the bitch’s milk.  Dogs suffering from this disease become restless, pant, and soon develop weakness, muscle tremors, gait abnormalities and occasionally, generalized seizure activity.

 

Excess vitamin A has been associated with congenital defects, including cleft palates. Folate deficiencies have been associated with fetal defects in humans.  Dogs produce sufficient vitamin C of their own and do not require supplementation.  Excess vitamin D may complicate the calcium mobilization ability of the bitch.  Supplementation of omega 3 fatty acids will maximize cerebral (brain) and retinal (eye) development in the fetuses.

Regular exercise during pregnancy is important in maintaining body condition.  Brisk walking and short swims are the safest form of exercise.

 

In late gestation, bitches carrying large litters may need to limit this to short walks. Performance bitches should stop heavy work activities during pregnancy; herding, agility, field and advanced obedience work are discouraged due to the risk of abdominal trauma and the potential stress to the fetuses.

 

During pregnancy, moderate uterine contractions occur approximately every 20 to 120 minutes and last 3 to 15 minutes.  During the contractions, the fetus does not breathe or undergo REM sleep.

 

Significant mental or physical stress on the bitch can cause adrenaline secretion by the bitch that decreases blood flow to the uterus and placenta, resulting in decreased fetal oxygen and can impair development and threaten survival. 

 

Routine vaccinations should be current or done prior to breeding. A puppy’s early immunity is dependent upon consumption of colostrum (bitch’s first milk) containing high levels of antibodies and, therefore, dependent on the bitch’s immune status.

 

Canine distemper and parvo titers can be measured for the pregnant bitch to assure appropriate levels are present.  Administration of modified live vaccines must be avoided during pregnancy.

 

Toxocara canis (roundworms) larvae encysted in muscle tissue of the pregnant bitch may be reactivated during the last trimester and migrate transplacentally to the developing fetuses.  It is important to realize that routine deworming of the bitch will not affect this process.  

 

The infection of developing fetuses can be interrupted by the administration of fenbendazole at 50mg/kg body weight from day 40 of gestation to day 14 after whelping.  Ancyclostoma caninum (whipworms) can also be transmitted through the placenta and is responsive to the above treatment.

 

External parasites are best controlled with environmental management and using a flea comb on the bitch.  Non-toxic environmental controls are now available.  Avoidance of organophosphates during pregnancy is recommended.  The newer flea control products are not, at this time, approved for use on pregnant bitches. 

 

Microfilaria of Ddirofilaria immitis can cross the placenta.  Pregnant bitches should be routinely tested for heartworms and maintained on heartworm preventive in at-risk areas.  The currently used heartworm preventives are safe in pregnant dogs.

 

Certain blood values are altered by pregnancy.  The packed cell volume (PCV) may decrease to approximately 40% by day 35 of gestation.  At delivery time, the PCV may be below 35%.  The immune system is moderately depressed during pregnancy, resulting in a decrease in serum IgG immunoglobulins.  Serum creatinine may decrease by 25 – 35%.  Fibrinogen and other coagulation proteins increase during pregnancy.

 

Hypoglycemia (low blood glucose) of pregnancy is also known as pregnancy toxemia.  This serious illness is most common in the thin, poorly conditioned bitches.  These dogs have inadequate fat stores, muscle mass, and carbohydrate diets.  They often present with nonspecific signs of gastrointestinal distress or seizures.

 

Because hypocalcemia presents with similar signs and can occur in term bitches, the veterinarian should evaluate both serum glucose and serum calcium. Treatment of hypoglycemia is with slowly administered dextrose-containing intravenous fluids.

 

Nutritional supplementation will be needed in bitches that do not voluntarily eat.  Termination of pregnancy may be necessary in severe cases.  Pregnant bitches that are maintained on diets deficient in carbohydrate may develop hypoglycemia in the last 2 weeks of gestation.  This can result in a significant increase in stillborn pups and in neonatal death in the first 3 days of life.

 

Pre-existing subclinical (disease present in dog without clinical signs) diabetes mellitus may be aggravated by pregnancy.  Sensitivity to insulin is decreased as early as 35 days of gestation and continues to decrease as pregnancy progresses.  Insulin should be given if indicated by carefully veterinarian-monitored blood glucose levels.

 

The varying demands and hormonal alterations during pregnancy and whelping may make glucose control difficult to obtain.

 

Although uncommon, failure to maintain an appropriate serum progesterone level throughout pregnancy is a potential cause of fetal loss.  Monitoring serum progesterone levels allows accurate diagnosis of this problem.  Serum progesterone above 2ng/ml are required to maintain pregnancy.

 

Monitoring of serum progesterone levels can be performed weekly if the bitch’s levels are 20 – 50 ng/ml or daily if the levels are 5 – 10 ng/ml.

 

Treatment of low progesterone can be performed with injections of progesterone in oil ( 2 – 3 mg/kg intramuscularly every 24 hours) or alternatively, trenbolone acetate (Regumate) at 0.088 mg/kg orally once daily.

 

Administration of any medication is best avoided in the pregnant bitch.  Some drugs have proven to be relatively safe, while others are definitely dangerous to the developing fetuses.  Many other drugs carry potential risks that have not been researched at this time.

The safest course is to avoid any medication of questionable safety and to only administer medications if absolutely necessary.

 

Drugs considered SAFE in pregnancy:

cephalosporins (antibiotic)

fenbendazole (dewormer)

penicillins (antibiotic)

ivermectin (dewormer)

amoxicillin with clavulanic acid (antibiotic)

praziquantel (dewormer)

clindamycin (antibiotic)

pyrantel pamoate (dewormer)

erythromycin (antibiotic)

diethylcarbamazine (dewormer)

milbemycin oxime (dewormer)

 

Drugs to AVOID during pregnancy:

aminoglycosides (antibiotic)

enalapril (cardiac medication)

tetracyclines (antibiotic)

theophylline (respiratory bronchodilator)

sulfonamides (antibiotic)

misoprostol (reduces risk of stomach ulcers)

chloramphenicol (antibiotic)

Diethylstilbestrol (estrogen)

metronidazole (antibiotic)

organophosphates (pesticide)

griseofulvin (antifungal)

omeprazole (reduces risk of stomach ulcers)

ketoconazole (antifungal)

aspirin (anti-inflammatory)

ketamine (anesthetic)

acepromazine (tranquilizer)

diazepam (anti-anxiety drug)

barbituates (sedatives)

glucocorticoids (hormones)

mitotane (pesticide)