module 7-estrous cycle

Question 1

who is considered the pioneer of hormone contraception

Answer 1

Dr. Wayne Bardin

Question 2

what did Dr. Wayne Bardin do

Answer 2

developed long lasting contraception that provided an alternative to daily oral pill

Question 3

what is Mirena? when was it FDA approved?

Answer 3

-an intrauterine device that releases a progesterone agonist(levonorgestrel)
-FDA approved in 2000

Question 4

hormones used in cosynch method, and their purpose

Answer 4

-GnRH: induce follicular waves/growth, induce ovulation
-Prostaglandin: regress CL
-CIDR(progesterone): Blocks ovulation

Question 5

timeline for cosynch method

Answer 5

-Day 0: GnRH injection, insert CIDR(grows new dominant follicle)
-Day 7: remove CIDR, give prostaglandin injection
*day 7: Place estrotect patch
and moniter for estrus(2-3
days)
OR
*Day 9: give GnRH injection and AI

Question 6

method for estrus synch in pigs

Answer 6

feed matrix for 14 days, then expose to boar, then breed

Question 7

what is prostaglandin secreted by

Answer 7

the uterus

Question 8

how does prostaglandin get to the ovary

Answer 8

counter-current exchange to ovarian artery

Question 9

does prostaglandin go through a counter-current exchange in horses? why/why not?

Answer 9

no, prostaglandin is not metabolized as well in horses so there is still enough left after traveling through the body to regress the CL

Question 10

division of estrous cycle based on ovarian structures

Answer 10

-follicular phase
-Luteal phase

Question 11

division of estrous cycle based on hormone profile

Answer 11

-proestrus
-estrus
-metestrus
-diestrus

Question 12

follicular phase traits
-dominant structure
-dominant hormone
-start
-end
-relative length

Answer 12

-dominant structure: follicle
-dominant hormone:estradiol
-starts with luteolysis
-ends with ovulation
-30% of cycle

Question 13

luteal phase traits
-dominant structure
-dominant hormone
-start
-end
-relative length

Answer 13

-dominant structure: CL
-Dominant hormone: progesterone
-starts with ovulation
-ends with luteolysis
-70% of cycle

Question 14

proestrus traits

Answer 14

-2-3 days
-increase estradiol
-decrease progesterone

Question 15

estrus traits

Answer 15

-24 hours(approximately)
-peak estradiol
-LH surge

Question 16

metestrus traits

Answer 16

-5 days
-decrease estradiol
-increase progesterone

Question 17

diestrus

Answer 17

-longest phase
-peak progesterone

Question 18

polyestrus

Answer 18

display estrus throughout the year

Question 18

seasonally polyestrus

Answer 18

display more than one estrus cycle during specific time of year

Question 19

monestrus

Answer 19

display estrus once a year
Ex: bear, foxes, dogs

Question 20

what animal is in constant estrus

Answer 20

rabbits

Question 21

length of menstrual cycle

Answer 21

28 days

Question 22

what is the start of the menstrual cycle

Answer 22

menses

Question 23

phases of menstrual cycle

Answer 23

-menses(CL regression)
-proliferative(rebuilding what was sloughed off)
-secretory

Question 24

agonists for estradiol

Answer 24

ethynyl estradiol mestranol

Question 25

agonists for progesterone

Answer 25

norethindrone levonorgestrel

Question 26

anestrus

Answer 26

no ovarian structures(not cycling)

Question 27

start of estrus cycle

Answer 27

ovulation

Question 28

proportional length of luteal and follicular phase in menstruation

Answer 28

50/50 split

Question 29

length of menses

Answer 29

2-5 days

Question 30

who was the last northern male white rhino, when did he die?

Answer 30

Sudan, 2018

Question 31

what is the possible hope for northern white rhinos

Answer 31

two viable embryos were produced that will likely be carried by southern white rhinos

Question 32

parts of the follicle

Answer 32

-granulosa cells -theca cells -follicular fluid -oocyte

Question 33

theca cells

Answer 33

-from stroma -respond to LH -convert cholesterol to testosterone

Question 34

granulosa cells

Answer 34

-from cortex -respond to FSH -convert testosterone to estrogen

Question 35

jobs of FSH

Answer 35

-granulosa cell mitosis -increase LH receptors -Steroidogenesis -effect preantral and antral follicles

Question 36

jobs of LH

Answer 36

-steroidogenesis -effect antral follicles -surge starts ovulation -resume meiosis

Question 37

gonadotropin independent

Answer 37

-initial development of follicle growth -primordial--->primary(preantral)

Question 38

gonadotropin responsive

Answer 38

-follicle can respond to gonadotropins but its not required(antrum formation)

Question 39

gonadotropin dependent

Answer 39

removal of gonadotropins results in atresia(tertiary and on)

Question 40

initial follicular recruitment

Answer 40

recruited from primordial follicle pool (gonadotropin independent)

Question 41

cyclic follicular recruitment

Answer 41

antral follicles recruited towards ovulation during specific estrous cycle(gonadotropin dependent)

Question 42

how many follicular waves occur throughout the estrous cycle

Answer 42

2-4

Question 43

what gonadotropin are dominant follicles more dependent on

Answer 43

LH and E2

Question 44

what gonadotropin are selected follicles more dependent on

Answer 44

FSH

Question 45

Selection phase -number selected -hormone profile

Answer 45

-1 follicle for single bearing, more for litter bearing -decreased FSH, LH dependence

Question 46

recruitment phase -number selected -hormone profile

Answer 46

-many follicles recruited -increased FSH

Question 47

dominant phase -number selected -hormone profile

Answer 47

-selected follicle becomes dominant -estrogen and inhibin(prevent FSH production)