Reproduction 2
Control of reproduction in male
Organs involved
Hypothalamus
Pituitary
Testes
Hormones
Gonadotropin releasing hormone
(GnRH)
Gonadotropins
Luteinizing hormone (LH)
Follicles stimulating hormone
(FSH)
Testicular hormones
Testosterone
inhibin
sperm
Dr. Craig
Darroch
Reproduction 2
Control of Reproduction in female
hypothalamus
pituitary
pineal gland
ovaries
Uterus
Dr. Craig
Darroch
Reproduction 2
Hormones
Melantonin from pineal gland affects hypothalamus to
control reproductive cycles in females that are
seasonally active
Mare is seasonally polyestrous
Estrous cycle evident in spring and early summer in NA
Tied to lengthening daylight hours in spring which affect
pineal gland and lower levels of melatonin
GnRH from hypothalamus controls release of
gonadotropins: FSH and LH from anterior pituitary
Dr. Craig
Darroch
Reproduction 2
Hormones
FSH (follicle stimulating hormone) from pituitary acts
on ovary to stimulate development of follicles
LH (lutenizing hormone) helps develop follicles and
then surge triggered by estrogen leads to ovulation
Estrogen produced in ovary from mature follicles
responsible for female sex behavior when in estrus
(heat) and for release of GnRH that brings about LH
surge and ovulation at end of estrus
Progesterone from CL in ovary inhibits release of LH
and FSH and responsible for maintenance of pregancy
Prostaglandin F2a from uterus brings about regression
of corpus luteum and decrease in progesterone
Dr. Craig
Darroch
Reproduction 2
Estrous cycle
Dr. Craig
Darroch
Reproduction 2
Estrous Cycle
See table 10.5 for species variations
Know for test!
Ovulation
Spontaneous ovulators
which release egg at or towards end of estrus
(heat) regardless if copulation occurs
Induced ovulators
which release egg in response to copulation
Dr. Craig
Darroch
Reproduction 2
Estrus (heat)
Stage of the estrus cycle when estrogen is being...