Reproduction Flashcards
What is the function of FSH? LH? Prolactin?
FSH - Gametogenesis
LH - Secretion of estrogen, progesterone , and testosterone
Prolactin - Lactation and development of the ovary during pregnancy
When does the hypophysis respond to hormonal influences?
D6 in male and D12 in female
When does ovarian follicle development begin? When does it mature? How is this correlated with signs of sexual maturity?
Begins at 3 weeks, matures by 30 days, and occurs concurrently with signs of sexual maturity.
When does puberty occur in the female? What changes are noted? How does this compare to onset of puberty in the male?
Estrogen-dependent changes in the female (cornification of the vagina) occur at 24-28 days. Puberty up to 2 weeks later in males.
Describe the mouse estrous cycle.
Polyestrous with 4-5day cycle
What visual signs signal proestrus and estrus?
Patency of vaginal orifice and swelling of the vuvla.
When does postpartum estrus occur? What is the comparative fertility, and why?
14-24 hours post birth. Less fertile and cornification of vagina not complete
Describe ovulation in mice.
Spontaneous, do not ovulate every estrus.
Why don’t mice ovulate every estrus?
Estrus is dependent on gonadal hormones, ovulation responds to gonadotropins.
What controls the cyclicity of estrus and ovulation?
Diurnal rhythm of photoperiod
How quickly does the Whitten effect take effect?
Estrus within 3 days of exposure to male/male urine.
What is the vaginal plug consist of? What area of tissue does it fill?
Mix of vesicular and coagulating glands. Fills cervix to vulva.
What is the result of physical stimulation of the cervix/vagina during mating?
Physical stimulation results in prolactin release. Prolactin causes CL to produce progesterone which causes a pseudopregnancy for 13 days. If pregnant, the placenta will take over progesterone production at 13 days.
Where and when does fertilization occur?
Ampulla, within 10-12 hours
How does lactation affect implantation and gestation?
Lactation can delay implantation, prolonging gestation by 12-13 days.
When are female breeders typically retired?
6 months
How does maternal care impact neonate body weight?
Accounts for up to 70% of variation in neonatal body weight.
Describe lactation length.
Occurs for 3 weeks, peaks at day 12.
What is the function of oxytocin?
Needed for nursing, not parturition or reproductive behavior.
How do neonates receive antibodies? When does maternal immunity begin to wane?
Majority through colostrum. Ab are secreted in milk throughout lactation. Decay of maternal immunity several months after weaning.
During proestrus, what is present on vaginal smear, in the uterus, and in the ovary and oviduct?
Smear - Epithelial to epithelial-cornified or epithelial-cornified cells; leukocytes to epithelial cells
Uterus - Increasing hyperemia and distension, active mitoses in epithelium, few leukocytes
Ovary/OD - Follicles enlarged and distended with liquor folliculi, few mitoses in germinal epithelium and follicular cells
During estrus, what is present on vaginal smear, in the uterus, and in the ovary and oviduct?
Smear - Epithelial-cornified to cornified + cells
Uterus - Max distension and activity, then decrease. No leukocytes
Ovary/OD - Ovulation, followed by distension of upper end of oviduct. Active mitoses in germinal epithelium and follicular cells
During metestrus, what is present on vaginal smear, in the uterus, and in the ovary and oviduct?
Smear - Cornified ++ cells, epithelial cells, leukocytes ++
Uterus - Decreased distension. Leukocytes in epithelium. Walls collapsed. epithelium degenerates. Mitoses rare
Ovary/OD - Follicles undergo atresia. Growing CL. Eggs in oviduct. Few mitoses in germinal epithelium and follicular cells
During dieestrus, what is present on vaginal smear, in the uterus, and in the ovary and oviduct?
Smear - Epithelial cells, leukocytes, more or less mucus.
Uterus - Pale, walls collapsed. Epithelium healthy with many leukocytes. Some secretion by uterine glands.
Ovary/OD - Follicles begin rapid growth towards end of period.
How is superovulation induced? What is the function of each hormone? What age of animals?
Females at 3-4 weeks of age.
PMSG Day 1 @1pm - Mimics oocyte maturation of endogenous FSH.
HCG Day 3 @11am - Mimics ovulation effects of LH. Endogenous release of LH happens 15-20 hr after midpoint of second dark cycle following PMSG, so give hCG a few hours before endogenous release.
Mating occurs at midpoint of third dark cycle.
At what age is a cell a zygote, morula, and blastocyst.
Day 0: Zygote
Day 1: 2 Cell
Day 1-2: 4 Cell
Day 2: Multicell
Day 2-3: Morula
Day 3-4: Blastocyst
What animals are used as recipients for embryo donation? How is pseudopregnancy induced?
8-10 week old females. LHRH for large cohorts, then mate to vasectomized male.
Males at what age should be used as donors for sperm cryopreservation?
12-24 weeks. Proven breeders.
