Exam 4- Female Reproductive Physiology I Flashcards
what is an estrous cycle?
period of heat, followed by ovulation and complex changes of the uterine lining
what is the physiology definition of an estrous cycle?
repeating physiological changes that are influenced by hormones controlling reproduction in placental animals other than humans and greater apes
what does the estrous cycle include?
behavioral heat/estrus
estrous cycle is events between two heats/estrus
ovulation
changes in uterus
what hormones control the estrous cycle?
ovarian and CNS hormones
what is anestrus?
time when animal not exhibiting estrous cycles
ovulatory follicles/corpora lutea not present
is anestrous part of the estrous cycle?
no
what animals have a polyestrus estrous cycle?
cows and pigs
what animal has a seasonally polyestrus estrous cycle- long day- spring breeding?
mare
what animals have a seasonally polyestrus estrous cycle- short day- fall breeding?
sheep and goats
what animal has a monestrus estrous cycle?
dog
what is transition?
right before and right after anestrus
who has transition periods?
irregular estrous cycle animals- short and longs cycles and silent heats
when does the follicular phase occur?
between luteolysis and ovulation
what does FSH induce without progesterone in the follicular phase?
ovulatory (Graafian) follicle
what does the ovulatory follicle produce?
estrogen
what does estrogen elicit in the follicular phase?
heat/estrus
without ______________, LH can spike, inducing _______________
progesterone
ovulation
what happens in the luteal phase?
growth and development of the corpus luteum
progesterone produced by corpus luteum
progesterone leads to changes in uterus
prostaglandin F2 alpha lyses corpus luteum
during the luteal phase, there is still some ____________________, but ___________________ do not form
follicular growth
ovulatory follicles
when does proestrus end?
at onset of estrus
during proestrus, ____________________ grow
preovulatory follicles
when does proestrus begin?
at luteolysis
what hormone influences the development of the ovulatory follicle, and therefore the start of the increase of estrogen production?
follicle stimulating hormone
what is the primary hormone in estrus?
estrogen
what induces ovulation?
luteinizing hormone spike
when does ovulation occur?
at end of estrus
when does metestrus occur?
ovulation to development of corpus luteum and progesterone dominance
what is formed in the metestrus phase?
corpus luteum
what starts to be secreted during metestrus?
progesterone
what is the longest stage of the estrous cycle?
diestrus
what happens during diestrus if pregnancy is not established?
corpus luteum is lysed
what is spontaneous ovulation?
ovulation occurs whether or not female mates
corpus luteum is produced
progesterone produced by corpus luteum
what is induced ovulation?
female must be mated to induce ovulation
physical stimulation
semen factors: ovulation induction factor
what species have induced ovulation?
domestic cat, camelids, rabbits, ferrits
true/false: a domestic cat will not form a corpus luteum (and therefore no progesterone or diestrus) unless she is mated
true
what happens if a ferret is not bred?
prolonged estrus
estrogen production
what is special about rats?
corpus luteum only lasts 4 days
will persist if mates: depends on prolactin production
is there estrus during the menstrual cycle?
no
what hormones play a role in the follicular phase?
decrease progesterone
increase GnRH
stimulates release FSH and LH
what does the dominant follicle secrete in the follicular phase?
E2 and inhibin
what stimulates the release of PGF2-alpha from the uterus in luteolysis?
oxytocin
what is the feedback in ruminant luteolysis?
double positive feedback
what happens when progesterone is no longer being produced?
no more negative feedback on hypothalamus
increase in GnRH leads to increased FSH and LH
increased follicular growth and production estradiol from follicles
what does increased estradiol lead to?
estrus
surge of GnRH from surge center
surge of LH
ovulation
what happens to ferrets if there are not mated?
prolonged estrus and estrogen production
what lyses the corpus luteum?
prostaglandin F2 alpha
