What is the function of GnRH?
Triggers the release of FSH and LH
what does Prostaglandin target
ovary
What are the 4 stages of the estrous cycle?
proestrus, estrus, metestrus, diestrus
What does the hypothalmus produce
GnRH
What is the CL?
hormone-secreting structure that develops in an ovary after an ovum has been discharged
What is the function of FSH?
stimulates growth and development of eggs and estrogen production
what is the function of Prostaglandin
signals to cause corpus luteum to become non-functional if fertilization does not occur
What happens during proestrus
restarts the cycle
begins after CL regression and ends at the onset of estrus, period of follicle(egg) growth, increase of estrogen
What does the ovary produce?
What are the 2 phases of the estrous cycle
1.follicular phase – short phase; period from regression of the CL to ovulation
2.luteal phase – long phase; period from ovulation to CL regression
What is the function of LH?
triggers ovulation(release of an egg), simulates the growth and development of corpus luteum
what does oxytocin target
Mammary Gland (myoendothelial cell)
Myometrium(layer of the uterus)
What happens during estrus
period of sexual receptivity to male, high estrogen levels
surge of LH
sometimes referred to as “heat”
Ovulation starts near the end of this stage
What does the anterior pituitary gland produce
FSH and LH
Which is the step and which is the cycle
Estrous and Estrus
Estrous with a O is the hormone cycle
Estrus without the O is the stage/step
What is the function of oxytocin?
causes contractions and leads to milk let down
what does estrogen target
Hypothalamus
what happens during metestrus
early postovulatory period
CL begins to develop and produce progesterone
Prepares the environment
what does the posterior pituitary gland produce?
oxytocin
What is polyestrous
uniform, regularly occurring estrous cycles throughout the year (example: cattle and swine)
What are 3 functions of Estrogen
Visual signs of estrus
Growth and development of the female reproductive organs
Growth and development of the mammary system
Development of female sexual characteristics and features
increase GNRH
What are 3 functions of Progesterone
prepares uterus for pregnancy and helps female animals cycle regularly
prepares uterus for implantation of the embryo
stops other eggs from forming
maintains pregnant condition
develops mammary glands which produce milk to feed young after they are born
decrease GnRH
what happens during diestrus
begins approximately four days after ovulation and ends with the regression of the CL
Find out if pregnant or not
what does the uterus produce?
Prostaglandin
What is the difference between menstruation and estrous cycle?
Menstrual
is calculated from menses to menses, ovulation occurs in the middle of the cycle. (it is what we can see!; humans, primates, etc.)
Estrous
is calculated from standing heat to standing heat, ovulation occurs 36 hours later (it is what we can see!; domestic animals)