Exam - Ovarian and Estrous Cycle Flashcards
what does the timing of formation and activation of primordial follicles differ between
species
when does clusters (cysts) of primordial follicles occur in rodents
birth
when do primordial follicles form in human and cows
mid gestation
what is the formation of primordial follicles independent of in mammals
gonadotropin (LH; FSH)
what is the primary follicle defined by
simple cuboidal cells surrounding the oocyte
what phase of prophase I does meiosis arrest in
diplotene stage
for oocyte growth, where is a lot of nutrients stored
in granules and vesicles
during oocyte growth what des the Golgi apparatus do
export ZP glycoproteins; cortical granules
when the centriole disappears during oocyte growth, which will be used
the male centriole
what is critical to prevent meiosis to proceeed
the communication through gap junctions between granulosa cells and oocyte
what do the multiplying theca cells on the outside of the basal lamina form
internal theca
external theca with muscular layer
how does nutrients and waste get to the secondary follicle
diffusion through the theca layer due to no blood vessels being within the follicle
what is cavitation
appearance of a fluid filled cavity
what are the 4 stages of antral follicular cavitation
small
medium
large
preovulatory
what multiples with antral follicles
both granulosa and theca cells
what is the theca externa
muscular innervated layer
what is the theca interna
produced androgens under the control of LH
when does the final maturation of oocytes occur
immediately prior to ovulation
when does the resumption of meiosis occur
during ovulation sequence
what is cytoplasmic maturation essential for
monospermic fertilization
processing of sperm
preparation for development to preimplantation
what does cytoplasmic maturation include
ability to release intracellular Ca upon fertilzation
production of proteins which will prepare male pronucleus
accumulation of mRNA, proteins, substrates and nutrients
what does the release of intracellular Ca do
triggers exocytosis of cortical granules
is it possible to observe several waves per cycle
yes
which are the only follicles that ovulate
dominant follicles present during estrus
why do only dominant follicles present during estrus ovulate
high levels ov progesterone during diestrus have negative feedback on GnRH
when should the oocyte encounter spematozoa in the oviduct
within 15-20 minutes of ovulation
what is mounting in cows stimulated by
Estradiol-17B
factors promoting mounting behaviour
size of sexually active group
time of day
footing
age/health of cow
head room
lack of distractions+human activity
temperate weather
what should the size of the sexually active group be
2+
what is the best time of day for mounting behaviour
night
what is the best footing for mounting behavour
dirt
non-slippery
why does the age/health of the cow matter for mounting behaviour
agility
what are non-behavioural changes at estrus
copious cervical mucous discharged
vulva reddening/swelling
low progesterone
high estradiol-17B
estrus-related odor
LH/FSH surge
met-estrus bleeding in cattle