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Puberty (ability to accomplish reproduction successfully) - Coggle Diagram
Puberty (ability to accomplish reproduction successfully)
hormones
testosterone
from fetal testis "defeminizes" the brain
female does not have testis to secrete testosterone and she therefore develops a GnRH source center in the hypothalamus
crosses BBB converted to estradiol in the brain and the estradiol "defeminizes"
alpha-fetoprotein binds to estradiol and prevent from crossing the BBB, estradiol cannot affect the hypothalamus
ovaries of prepubertal females will respond by producing follicles and estradiol when stimulated with FSH and LH
sudden bursts of GnRH: preovulatory GnRH surge
GnRH neurons must fire frequently and release large quantities of GnRH
requirements for puberty
secretion of the GnRH at the appropriate frequency and quantities to stimulate gonadotropin release by the pituitary
female
age at first estrus (heat)
become sexually receptive and displays her first estrus
age at first ovulation
need to manual or visual to valuate. Palpation or ultrasonography of ovary, difficult to determine
Male
age when behavior traits are expressed (mounting and erection)
age at first ejaculation (coordinate nerves)
age when spermatozoa first appear in the ejaculation
age when the ejaculation contains a threshold number of spermatozoa
puberty will be initiated when the GnRH neurons can respond completely to positive and negative feedback
external factors
the photoperiod that the animal is experiencing during the onset of puberty
the presence or absence of the opposite sex during the peripubertal period
season during which the animal is born
density of the groups (within same sex) in which the animals are housed
social cues (transmitted by pheromones)
group size
genetics
fatness
energy towards maintenance of vital physiologic functions
adipocytes (fat cells) secretes leptin