Week 2 Flashcards
Label the female reproductive tract
Label the ovary histology
Describe the cells of follicular development
What kind of follicle is this
Primordial
Primary oocyte surrounded by simple squamous epithelial granulosa cells
What kind of follicle is this
Primary follicle
First developmental stage of growing follicle
Primary oocyte surrounded by simple cuboidal epithelial granulosa cells
What kind of follicle is this
Secondary follicle
Granulosa cells proliferate & form stratified epithelium (multiple layers of granulosa cells)
What kind of follicle is this
Early antral follicle
Characterised by fluid-containing cavity (antrum)
Theca cells differentiate into 2 layers
What kind of follicle is this
Antral follicle
Granulosa cells form thickened mound (cumulus oophorus) which projects into antrum
What is corpus haemorrhagicum
early corpus luteum
Label the corpus luteum histology (bovine)
Label the ovary cross section
Where would you find primordial & primary follicles
in cortex near ovarian surface epithelium
Label the antral follicle
Label the corpus luteum
What cell types in the CL produce progesterone
small & large luteal cells
What are the origins of small and large luteal cells
Theca (small)
Granulosa (large)
label the layers of the oviduct wall
Label the uterine tube (oviduct)
What parts of the uterine tube are shown
What are the 3 layers of the uterus wall
Label the uterus
Label the uterus
What hormone suppresses oestrus and why
Progesterone
To prepare uterus for pregnancy. Blocks LH surge (further ovulation)
What does FSH do in dioestrus
stimulates development of antral follicles
Draw graph of progesterone & FSH in oestrus cycle
Describe the cow oestrous cycle
21 day oestrous cycle
17 day luteal phase
3 days proestrus (falling progesterone)
1 day standing oestrus
LH surge mid-oestrus
- ovulation 24 hours after LH surge
- thus ovulation 12h after end of oetrus
When to mate a cow
Fill in the table
Describe timing of insemination/mating in cow
detecting problem because they dont show a lot of signs
Describe timing of insemination/mating in ewe
Describe timing of insemination/mating in sow
Describe timing of insemination/mating in mare
hard to predict because length is so variable
Describe timing of insemination/mating in bitch
obligatory anoestrus after oestrus so problem if opportunity is missed
Describe oestrous behaviour in cows
standing to be mounted is golden standard (optimum timing)
Bloody discharge on tail shows she was in oestrus 2-3 days ago (not menstruation)
why is oestrous detection in cow critical
What are some key strategies for oestrous detection in cow
Examine cow >4x per day for >30 min (not when they come in for milking or feeding as they might be distracted)
Classic detection aids (change color)
Remote/electronic aids (monitors position)
Van Eerdenburg’s scoring
How can oestrous be detected in cow by clinical assessment
- low plasma/milk progesterone (indicates oestrous is imminent if previously high)
- clinical detection of large dominant follicle in absence of CL
What factors might inhibit oestrous behaviour in cow
What hormones can be used to synchronise ovulation (for AI)
GnRH & PGF2a
What are signs of oestrous in ewe and how is it detected
What are signs of oestrous in sow
What are signs of oestrous in mare and what are some important considerations
How can oestrous be detected in mare by clinical assessment
What are signs of prooestrus and oestrus in bitch
How can oestrous be detected in bitch by clinical assessment
- assessment of vaginal epithelial cells (shape changes as she comes into oestrus)
- assessment of vulval softening
- examination of appearance of vaginal wall - plasma progesterone concentrations
- detecting rise in progesterone that precedes ovulation
- follicles release progesterone just before ovulation
describe oestrous and its signs in the queen
Has to mate to have LH surge - driven by mating not hormones (often need multiple matings for surge)
What features of this cat indicate that she might be in oestrus
What is anoestrus
Period where oestrus doesnt occur (not cycling)
Can be normal process
Pigs anoestrus until piglets are removed, mare in winter and dogs after luteal phase
What are some reasons for anoestrus occuring (physiological & pathological)
What is silent oestrus
Describe silent oestrus in dairy cows
List the 2 gonadotrophins and their functions
Where are the gonadotrophins (LH & FSH) produced
How is the production/release of LH & FSH (gonadotrophins) controlled
controlled by GnRH, inhibin, oestradiol
Draw the female HPO axis
Draw the hormones of a typical 21 day oestrus cycle
What stages of oestrus cycle are in follicular phase
What stages of oestrus cycle are in luteal phase
Draw a schematic representation of polyoestrus cyclicity
Draw schematic representation of pregnant vs non-pregnany sow
Describe bitch oestrus cycle
non-seasonal
monoestrus (7 month interval between oetrus)
spontaneous ovulator
Draw schematic representation of oestrous cycle of bitch
What is the role of prolactin in the bitch
How can termination of the luteal phase of bitch be achieved
Describe pseudopregnancy in bitch
Draw a progesterone profile during non-pregnant luteal phase of cow vs bitch
Describe cat oestrus
Seasonal (long day breeder)
polyoestrus
induced ovulator (also ferret & rabbit)
- absence of stimulation = ovulation doesnt occur
- absence of ovulation = regression of follicles & no luteal phase
Which phase is longer follicular or luteal
Luteal
Fill in the oestrus cycles characteristics table
Describe ovarian cysts
No/small LH surge:
- Poor follicle quality with low oestradiol production –> insufficient negative feedback on the hypothalamus and pituitary gland.
- Stress or nutritional deficits can also impair GnRH release
Follicular type characteristics:
- prolonged production of estrogen by the cystic follicle –> constant estrus or hyperestrogenism.
Luteal type characteristics:
- Derived from the corpus luteum, these cysts produce progesterone, which suppresses estrus behavior, resulting in no evident signs of heat.
What causes anovulatory anoestrus
tiny ovaries
What causes persistent corpus luteum
luteolysis gone wrong (not enough prostaglandin)
Label the ovary
What are the 2 major structures of the ovary
What takes longer preantral or antral follicle growth
Preantral (months) compared to antral (days-weeks)
Describe antral follicle selection
Describe oocyte growth & communication
zona pelludica protects oocyte
What are the phases of antral follicle growth
- recruitment (of small antral follicles)
- selection (medium)
- dominance (large)
Most follicles die by atresia
Describe antral follicle recruitment
Describe antral follicle dominance
Describe what is happening here
In what stages of follicle growth are these follicles
How is follicular oestradiol produced
Describe FSH & LH in oestradiol production
Theca cells have LH receptor
LH binding to receptor causes cholesterol to be converted to testosterone
Testosterone goes into granulosal cell
FSH binds to FSH receptor in granulosal cell and causes testosterone to be converted to oestradiol
Describe hormones leading to ovulation
Describe the role of PGE2 and PGF2a in ovulation
Preovulatory LH surge causes increase in PGE2 and PGF2a
PGE2 => increased blood flow to ovary and dominant follicle => oedema => increased follicular pressure => ovulation
PGF2a => release of lysosomal enzyme which weakens follicular wall and increased contraction of ovarian smooth muscle which increases follicular pressure => ovulation
Describe oocyte maturation
Where does the corpus luteum grow from
remnants of follicle
Define luteinisation
role of LH
pituitary hormone
causes ovulation & subsequent development & maintenance of CL
Define luteotroph
hormone that stimulates CL (e.g. LH)
define luteolysis
process whereby luteal tissue undergoes regression & cell death
define luteolysin
a luteolytic factor
describe the formation of the CL