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THERIO L1-3 Cow Cycle Spermatogenesis Oogenesis Fertilization

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drhartz's version from 2017-09-14 03:16

Cow Cycle

Question Answer
Proestrus begins with the completion of what?luteolysis
Proestrus what hormones dec/inc ?increase --> estrogen & baseline LH
decrease --> progesterone, rapidly
Late proestrus is the onset of what?Estrus!
During Estrus how does the female act standing heat - stands to be mounted by male
During Estrus what does estrogen do? (2) rises to a peak then declines after surge
During Estrus what hormone surge follows estrogen surge?LH
During estrus what triggers ovulation? when does ovulation occur? LH surge
ovulation DOES NOT occur in estrus. it occurs in metestrus 12-18 hours after estrus
AI admin when?before ovulation within 12 hours of estrus --> takes sperm 10-12 hours to get to oviduct/oocyte only receptive 10 hours
during metestrus what is developing?corpus hemorrhagicum is developing into CL
during metestrus what hormones are high and low?low blood estrogen and LH
increasing progesterone
metestrus causes what behavorial change in the female?low estrogen and dominant progesterone causes END to standing heat
during metestrus what is happening with CL?maturation of CL to mature progesterone production
during diestrus what is happening with CL?the CL is mature at onset of diestrus it produces significant progesterone secretion until luteolysis
PGF2a secreated at the end of diestrus causes a drop in what? what day does this occur?progesterone on day 16
the presence of an embryo in diestrus prevents what surge? and causes release of what instead?PGF2a surge instead IFN tau is released!
during luteolysis what is released? where is it released from? what is its function?PGF2a --> from the uterus --> regression of CL & its progesterone production
what is "maternal recognition of pregnancy"?process whereby the conceptus signals its presence to the maternal system and prolongs the lifespan of the corpus luteum
when does ovulation occur?24-30 hours after estrus onset or 12 hours after estrus ends
when does mucus drip from vagina?during estrus
when does vaginal bleeding occur? for how long?metestrus for 3 days
how many days is proestrus?3 days .. begins on day 18 to day 21
how long does LH surge last during late proestrus?8-12 hours
LH triggers what to happen? (2)resumption of Meiosis 1 & ovulation
how long is estrus?12-18 hours
how long is metestrus? what day does it begin?4-5 days ... 18 hours after day 0 to day 5
when is CL unresponsive to PGF2a ?4 days after ovulation or until day 5 (end of metestrus)
what day is the onset of estrus?day 0
is the CL responsive to PGF2a during metestrus?NO
what days of the cycle is the CL mature and producing progesterone?day 5.. until luteolysis at day 16-17
what day does diestrus end and proestrus start?day 18
how long is PGF2a secreted by the uterus?36 hours at day 16
disruption/ hysterectomy of what 3 things delays lutealysis? why?endometrium, uterine vein ipsilateral to CL, uterine horn ipsilateral to CL --> endometrium produces PGF2a and ipsilateral uterine vein from uterine horn brings it to CL for regression
PGF2a is transfered from uterine vein to uterine artery in which speciesewe, cow, sow ( not horse )
PGF2a admin in what days of cycle will cause luteolysis ?day 6-18
after luteolysis how many days until estrus begins ?3 days
what 3 things does conceptus do for recognition of pregnancy?elongates from sphere to tube to fialmentous form, contacts entire surface of uterus, produces IFN-tau
by what day must an embryo be ipsilateral to ovary with CL to prevent luteolysisday 16
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Hormones used as drugs

Question Answer
implication of big vs small molecules?M.W > 5000 is antigenic
large antigenic moleculesLH, FSH , eCG, hCG
Progesterone - where produced?CL & placenta
Progesterone - roleessential for maintenance of pregnancy, decrease causes parturition
which part of cycle prevents ovulation with progesterone admin?proestrus - prevents GnRH/FSH/LH surge no estrogen/LH surge
Progesterone big or small ?small
Testosterone - where produced ?leydig cells of seminiferous tubules & theca cells of primary follicle
testosterone - role?spermatogenesis & conversion to estrogen in granulosa cells for estrogen surge
testosterone - big or small?small
Estrogen produced where?granulosa cells of primary follicle
estrogen - role?estrus! estrus behavior, activates LH surge!
estrogen big or small ?small
PGF2a produced where ?nonpregnant uterus
PGF2a role ?luteolysis .. starts new estrus cycle
PGF2a admin during what part of cycle causes luteolysisdiestrus day 6-18
GnRh produced wherehypothalamus
GnRH rolestimulates FSH/LH release
GnRH sizesmall
Oxytocin producedposterior pituitary and CL
Oxytocin rolesimulates endometrium to produce PGF2a
Oxytocin sizesmall
LH produced where?anterior pituitary
LH roleLH surge --> inititates lutelization of follicle to produce progesterone, progression of meoisis 1, OVULATION! :)
LH sizelarge
FSH producedanterior pituitary
FSH rolefollicular maturaion / folliculogenesis
FSH sizelarge
eCG (horse LH) roleacts as FSH in other species
eCG sizelarge
hCG roleacts as LH in other species
hCG sizelarge
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