quiz 8 Flashcards
(49 cards)
describe the luteal phase
it takes several days for a CL to form and P4 to rise
what occurs when P4 levels fall
inhibin is removed from the surge center
when does the corpus hemorrhagicum present itself
1-3 days after ovulation
what are granulosa and theca cells turned into
large and small luteal cells
describe large luteal cells
undergo hypertrophy, which increases muscle mass 3 fold
describe small luteal cells
undergo hyperplasia, which increases cell production 5-fold
what does the vascularization of the CL cause
steroid synthesis and delivery of hormones
what does insufficient CL functions cause
failure to remain pregnant
where do waves come from
the tonic center
what supports the embryo before the placenta forms
endometrial glands
what is the primary hormone
PGF2a
describe luteolysis in:
normal uterus
total hysterectomy
contralateral hysterectomy
ipsilateral hysterectomy
normal CL lifespan
longer CL lifespan
normal CL lifespan
longer CL lifespan (35+ days)
mares do/do not have a countercurrent exchange
do not
when is PGF not effective in most animals? in swine?
in the first five days
in the first 10 days
what do luteal cells use to react
Ca second messenger
when does P4 increase
when oxytocin is low
define auto-amplification loop
PGF2a induces PGF2a production in the CL
self-sustaining loop
define feedback loop
PGF2a induces oxytocin in the CL, which releases more PGF2a
positive feedback loop
what does luteolysis cause
decreased blood flow
cellular response
immune response
what is the CL lifespan in a human
12-14 days
what are the 5 causes of manipulating estrus
grouping females for parturation
reducing/eliminating estrus detection
needed for artificial insemination
embryo transfer
schedule for male availability (in horses)
what hormones help with time
PGF2a, GnRH, progestins
what hormones help with superovulation
FSH, eCG
when is PGF2a active for most animals? for swine?
on days 5-17
12-15
