Repro 8 Lecture 45 Parturition and Lactation

Question 1

What are the two stimulants of oxytocin release in the cow?

Answer 1

External Stimuli
Suckling

Question 2

Time for endometrial repair in the dog?

Answer 2

130-140 days

Question 3

Fetal stress leads to the release of __________ from the fetal ______________

Answer 3

CRH - corticotrophin releasing hormone
Hypothalamus

Question 4

The release of CRH from the fetal hypothalamus leads to the release of ___________ from the fetal ___________

Answer 4

adrenocorticotrophic hormone (ACTH)
pituitary

Question 5

The release of adrenocorticotropic hormone from the fetal pituitary leads to the release of _____________ from the fetal _____________

Answer 5

cortisol
adrenal gland

Question 6

List the endocrine events following fetal stress that initiate parturition?

Answer 6

Fetal stress –> CRH released from fetal hypothalamus –> ACTH released from fetal pituitary –> cortisol released from fetal adrenal gland

Question 7

3 enzymes involved in converting P4 to E2

Answer 7

Hydroxylase
Desmolase
Aromatase

Question 8

What does fetal cortisol do in relation to hormones?

Answer 8

Promotes the conversion of progesterone to estradiol

Question 9

Fetal corticoids promote conversion of __________ to __________ and cause the placenta to synthesize PGF2-alpha (prostaglandins)

Answer 9

Progesterone to estradiol

Question 10

Fetal corticoids promote conversion of progesterone to estradiol and cause the placenta to synthesize________________

Answer 10

PGF2-alpha (prostaglandins)

Question 11

What hormone serves to facilitate myometrial contractility?

Answer 11

Oxytocin

Question 12

As fetal cortisol levels rise progesterone levels ________

Answer 12

fall

Question 13

What hormone is stimulated by prostaglandins being produced by the placenta?

Answer 13

Relaxin

Question 14

What are the 3 stages of parturition and what are they generally characterized by?

Answer 14

Stage I - fetal stress leads to a cascade of hormones which leads to fetal maturation and positioning and priming of the birth canal
Stage II - expulsion of the fetus
Stage III - expulsion of the fetal membranes

Question 15

What does relaxin do?

Answer 15

Causes softening of the connective tissue in the cervix and increases the elasticity of the pelvic ligaments

Question 16

In the cow: Cortisol mediated synthesis of __________from placenta leads to ______ and initiation of myometrial contractions

Answer 16

PGF2alpha
Luteolysis

Question 17

Waterbag (other name/proper anatomical term)

Answer 17

Chorioallantois

Question 18

What marks the end of stage 1 of parturition in cattle?

Answer 18

Dilation of cervix and entry of fetus into the birth canal + the rupture of the chorioallantois

Question 19

What is the fetal orientation in birth canal? (cows)

Answer 19

Anterior presentation; dorsal presentation; head extended over fetlock joints

Question 20

Ferguson reflex

Answer 20

Fetal distension on cervix stimulates a series of endocrine responses leading to oxytocin release and more myometrial contractions

Question 21

In cattle what is stage III of parturition characterized by?

Answer 21

Detachment and expulsion of cotyledonary placenta

Question 22

The dislodging of cotyledons is faciliated by strong _________ of chorionic villi.

Answer 22

vasoconstriction

Question 23

The chorionic vili should be dislodged from the maternal side to avoid potential trauma which can lead to:

Answer 23

hemorrhage and metritis

Question 24

Which species can withstand retained fetal membranes?

Answer 24

Cattle

Question 25

Time taken for endometrial repair in cows

Answer 25

25-30 days

Question 26

Time taken for resumption of ovarian function in cow

Answer 26

4 weeks

Question 27

What purpose do myometrial contractions serve during the puerperium period? (3)

Answer 27

prevent hemorrhage expulsion of lochia involution

Question 28

The mare may show estrus within how many days after foaling?

Answer 28

8-12 days

Question 29

In the mare, how long for endometrial repair?

Answer 29

12-15 days

Question 30

time for involution in mare:

Answer 30

12 hours (fast af boi)

Question 31

Characteristic appearance of sow lochia

Answer 31

creamy coloured - will appear for a week

Question 32

Involution time in the sow

Answer 32

21 days

Question 33

Nursing sows are in what stage of the ovarian cycle?

Answer 33

Anestrus

Question 34

How long before sows go into estrus after weaning?

Answer 34

5-7 days

Question 35

How long are Does (sheep) expulsing lochia? what concern about their lochia should be noted?

Answer 35

4 weeks - potential for pathogens so this should be monitored but is not the same as postpartum metritis

Question 36

How long and what is the appearance of lochia in dogs?

Answer 36

dark green mucoid lochia will be discharged for up to 12 hours and then it will be reddish brown for a week

Question 37

time until next estrus for dogs after parturition?

Answer 37

7 months

Question 38

The role of cortisol during parturition is to A. Induce fetal maturation B. Stimulate the conversion of progesterone to estradiol C. Promote synthesis of PGF2a D. All of the above

Answer 38

D - All of the above

Question 39

What is the best indication of stage 1 of foaling in mares?

Answer 39

Sweating

Question 40

About how long is stage II in the mare?

Answer 40

20 minutes

Question 41

Among the following which statement is true with respect to foaling A. Expulsion of the fetal membrane does not occur until 3 h after foaling B. Foals are usually born in intact chorioallantois C. Foals may born in intact amnion D. Disconnecting the foal from the mare by severing the umbilical cord is a common management procedure

Answer 41

C - Foals may born in intact amnion

Question 42

How long are stages I, II, and II in ovine and caprine?

Answer 42

Stage I - 2-12 hours Stage II - 1-3 hours Stage III - 1 hour

Question 43

How long can fetal membranes remain in ovine and caprine before concern of retained membranes?

Answer 43

12 hours

Question 44

How are fetal membranes expelled in porcine?

Answer 44

Usually expelled after the last piglet

Question 45

How long between piglet births before there is cause for concern?

Answer 45

more than 15 minutes between piglets is abnormal

Question 46

what is the colour of the first discharge before the first pup is born?

Answer 46

Pink to dark red During parturition dark green to black dischage is present due to breakdown of marginal hematoma

Question 47

What actions happen during the puerperal period?

Answer 47

Myometrial contractions endometrial repair resumption of ovarian function elimination of bacterial contamination

Question 48

A healthy normal sow that farrows, nurses, and subsequently weans a litter of pigs at 28 days postpartum is most likely to exhibit a fertile estrus: A. 2 to 3 days after weaning B. Within 5 to 7 days after weaning C. 60 days after farrowing D. 21 days after weaning

Answer 48

B - Within 5 to 7 days after weaning

Question 49

How long are stages I, II, and II in cattle

Answer 49

Stage I - 6 hours Stage II - 30-60 minutes Stage III - 8 hours

Question 50

The role of cortisol during parturition is to A.Induce fetal maturation B.Stimulate the conversion of progesterone to estradiol C.Promote synthesis of PGF2a D.All of the above

Answer 50

D - all of the above

Question 51

How long are stages I, II, and II in horses

Answer 51

Stage I - 1-4 hours Stage II - 20 minutes Stage III - 3 hours

Question 52

How long can placenta remain in the horse before concern?

Answer 52

3 hours

Question 53

Cervical star

Answer 53

contact area between the cervical folds and chorion - usually the site of rupture

Question 54

Which fetal membrane layer is most closely associated with the fetus?

Answer 54

Amnion

Question 55

During suckling, what cell type are stimulated in the mammary tissue that facilitates release of milk?

Answer 55

Myoepithelial cells