Pregnancy And Parturition Flashcards
What is the function of the hormone relaxin
- Prevents uterine contractions before parturition
- Loosens connective tissue + ligaments in the cervix before parturition
What hormone causes uterine contractions
Oxytocin
Which animals have an endometrial cup
Mares (horses)
What hormone stimulates the growth of mammary glands
Placental lactogen
What does foetal presentation mean
Whether they are longitudinal, transverse or vertical
What does foetal position mean
The relationship of the foetal back to the dorsal surface of the birth canal
Ex) dorsal, ventral, right,left
What does foetal posture means
Placement of movable appendages ex) flexure + extension
What is the function of the placenta
Transport metabolic substances (O2 and nutrients) to embryo
Describe the 1st stage of parturition
Cervical dilation
Pelvic ligaments relax due to relaxin
Oestrogen secreted
Progesterone inhibited, allowing contractions
Foetal reposition
What function of progesterone in parturition
Inhibits uterine contractions
Describe the 2nd stage of parturition (delivery)
Abdominal wall contractions move foetus towards pelvic inlet
Oxytocin secreted due to foetal pressure
Placental membrane (chorioallantois) ruptures releasing allantoic fluid
Water bag expelled
Foetal structures show
Umbilical could ruptures
Describe the 3rd stage of parturition (expulsion)
Oxytocin and PGF2 cause myometrial contractions
Foetal membrane disconnects to endometrium
Foetus is expelled
Which species expel the foetus and placenta separately
Monotocous
(Horse, cow, primates)
Describe polytocous birth
(Dog cat pig)
expel the foetus then placenta, then next foetus then next placenta.
