Pregnancy

Question 1

what is the normal canine gestation length from the following events:
a. breeding
b. LH peak
c. ovulation

Answer 1

a. breeding – 58-72 days
b. LH peak – 65 days
c. ovulation – 63 days

Question 2

what hormones are important for maintaining pregnancy in dogs?

Answer 2

1. progesterone – comes from CL and maintains pregnancy
2. relaxin – comes from placenta
3. prolactin – from the pituitary gland; luteotrophic and maintains normal progesterone levels

Question 3

how can we diagnose pregnancy in small animals?

Answer 3

palpation – string of pearls
ultrasound
radiographs
relaxin test (not commonly used)

Question 4

what things are important to consider in regards to the management of a pregnancy bitch?

Answer 4

1. biosecurity – 3 wk prior and after birth (herpes)
2. nutrition – eat puppy or all life stages food; 1.5-2x more calories in last 3 wk gestation, 3x more during lactation; avoid large breed formulations (low in Ca and calories)
3. vaccinations – have UTD prior to breeding
4. deworming with fenbendazole at d41, d42, and d43

Question 5

When can you perform a pregnancy check?

Answer 5

~ 28 days after ovulation

Question 6

when can you perform a pre-whelping radiograph in reference to ovulation

Answer 6

~ 56 days after ovulation

Question 7

what are you evaluating when you perform ultrasound on a pregnant bitch?

Answer 7

1. fetal viability (heart flutter and relative size of fetus)
2. approximate # of fetuses

Question 8

You are performing ultrasound on a pregnant bitch and you see no embryo proper in one of the cranial embryos. When you move caudally, you see an edematous “sphere” with fluid inside.
What is your interpretation of these findings?

Answer 8

these findings are indicative of non-viable embryos/fetuses.

Question 9

If you perform an ultrasound on a pregnant bitch and you determine that she has had a couple of embryo resorptions, but still has a few vital embryos and is otherwise healthy, what should be your plan for the next steps in managing her pregnancy?

Answer 9

1. monitor her by rechecking ultrasound in 1 week to ensure no additional pups are resorbing.
2. progesterone level check (this hormone maintains pregnancy and if levels are too low, this could be why she lost the embryos)
3. vaginal cytology – to look for any evidence of infection or inflammation
4. CBC/Chem – to look for any evidence of infection or inflammation

Question 10

what are a few common causes for fetal resorption?

Answer 10

1. infectious causes: bacterial (E. coli, strep, staphs, salmonella, campylobacter jejuni, mycoplasma, ureaplasma), or viral (herpes, parvo, distemper, adenovirus)
2. physiologic reduction (overcrowding or genetic abnormality of embryo)
3. inadequate nutrition
4. toxin exposure
5. some drugs
6. cystic endometrial hyperplasia
7. hypoluteoidism
8. endocrine disorders
9. trauma

Question 11

Before how many days is pregnancy loss considered “embryonic resorption”?

Answer 11

less than 35 days

Question 12

progesterone levels must be maintained above ___ ng/mL to maintain pregnancy.

Answer 12

2

Question 13

T/F: progesterone levels decrease throughout the pregnancy

Answer 13

true

Question 14

If you perform an ultrasound on a pregnant bitch and you determine that all of the embryos are nonviable, what should be your plan for treatment?

Answer 14

complete emptying of the uterus either spontaneously, through medical management (PGF2a, aglepristone, or cabergoline), or spay.

Question 15

What recommendations do you make to an owner that is preparing their dog for whelping?

Answer 15

1. prepare the whelping box
2. monitor her temperature 2-3x/day (when it drops below 99, she will whelp within 24 hr)
3. make sure she continues to eat
4. biosecurity

Question 16

How can you recognize stage 1 of labor (this stage can last up to 18 hr)?

Answer 16

anorexia, nesting, panting, temperature drops

Question 17

Stage ___ of labor is charcterized by active contractions and pushing.

Answer 17

2

Question 18

What is the most important thing to occur in stage 3 of labor?

Answer 18

passage of placentas

Question 19

T/F: it is considered normal for a dog to push for 1 hour prior to the first puppy being born and subsequent puppies should arrive every 30 min

Answer 19

true
anything >1 hr without 1st puppy is bad; >30 min of pushing without the rest of the puppies is also bad.

Question 20

What are alarming things to see during labor that should prompt an owner to call the vet right away?

Answer 20

1. black vulvar discharge
2. mod to large amt fresh blood
3. foul-smelling purulent discharge
4. green vulvar discharge and no puppies

Question 21

What options can you offer to an owner whose dog was mismated today?

Answer 21

1. ultrasound the dog in 25-30 adys to confirm a pregnancy
2. give prostaglandins to lyse her CL and cause resorption AFTER confirming pregnancy at 25-30d post-mating.

Question 22

You can use aglepristone (a progesterone-receptor blocker) to terminate a pregnancy up to ______ after mating.

Answer 22

45 days.

this medication will prevent implantation and cause embryo resorption.

Question 23

T/F: the side effects of aglepristone are extensive

Answer 23

false they are actually minimal.

Question 24

T/F: you can give prostaglandinF2a to a clients dog who was mismated today.

Answer 24

false – you need to confirm the pregnancy first.

Question 25

What effects does PGF2a have on pregnacy? (3)

Answer 25

1. luteolysis
2. myometrial contractions
3. cervical dilatation

this drug has many side effects