Review of Reproduction in Female Domestic Animals

Question 1

where is GnRH produced

Answer 1

hypothalamus

Question 2

where is LH produced

Answer 2

anterior pituitary

Question 3

where is FSH produced

Answer 3

anterior pituitary

Question 4

where is progesterone produced

Answer 4

CL

Question 5

where is inhibin and activin produced

Answer 5

granulosa cells

Question 6

where is estradiol produced

Answer 6

granulosa cells

Question 7

where are prostaglandins produced

Answer 7

uterine endometrium

Question 8

reproductive function of dopamine

Answer 8

inhibits production of prolactin

Question 9

reproductive function of oxytocin

Answer 9

stimulates smooth muscle contractions of uterus and milk letdown

Question 10

reproductive function of progesterone

Answer 10

maintenance of pregnancy

Question 11

what is the fergueson reflex?

Answer 11

pressure in the birth canal or on the cervix: stimulates release of oxytoxin to further stimulate contractions

Question 12

what hormone is stimulates by high frequency pulses of GnRH?

Answer 12

LH

Question 13

what hormone is stimulated by low frequency pulses of GnRH?

Answer 13

FSH

Question 14

what hormones are associated with proestrus

Answer 14

declining progesterone, increasing estradiol

Question 15

what hormones are associated with estrus/heat

Answer 15

high estrogen

Question 16

what hormones are associated with metestrus

Answer 16

declining estrogen, increasing progesterone

Question 17

what hormones are associated with diestrus

Answer 17

high progesterone

Question 18

what hormones are associated with anestrus

Answer 18

low hormonal action

Question 19

what is the follicular/luteal phase

Answer 19

follicular: rising estrogen, intense LH pulses, LH surge, ovulation
luteal: progesterone higher than estrogen, inhibition of LH, no heat

Question 20

estrus vs estrous

Answer 20

estrus: noun : cycle itself
estrous: associated occurrences like behaviors

Question 21

Describe a primordial, primary, secondary, and tertiary (antral) follicle

Answer 21

a. primordial – single layer of flat granulosa cells
b. primary – single layer of cuboidal granulosa cells
c. secondary – multiple layers of cuboidal granulosa cells
d. tertiary (antral) – presence of a fluid filled antrum, multiple layers of granulosa, theca cells, has FSH and LH receptors

Question 22

function of thecal cells

Answer 22

convert cholesterol to androgens

Question 23

function of granulosa cells

Answer 23

convert androgens into estrogens (FSH)

Question 24

hormonal process of ovulation

Answer 24

LH surge stimulates relaxin and prostaglandins from granulosa, connective tissue of follicle weakens and leads to rupture

Question 25

what are species that are induced ovulators

Answer 25

cats, camelids, ferrets, rabbits

Question 26

what is special about progesterone production in the dog?

Answer 26

progesterone rises before ovulation

Question 27

what hormone causes CL regression

Answer 27

prostaglandins

Question 28

what species don't use prostaglandins

Answer 28

dogs and cats

Question 29

what species experience unilaterla ovarian development

Answer 29

avians

Question 30

can you spay a bird

Answer 30

no

Question 31

can you spay a reptile/chelonian

Answer 31

yes

Question 32

what is a seasonal breeder? what causes changes in seasonal cyclicity?

Answer 32

only breed during certain times of year melatonin

Question 33

what is a determinate layer?

Answer 33

failure to lay additional eggs in case of egg loss chelonians, reptiles, budgies, parakeets, most avians but NOT CHICKENS DUCKS ETC

Question 34

what species would you perform an ovariectomy on?

Answer 34

large animal

Question 35

what species would you perform an ovarihysterectomy on?

Answer 35

small animal

Question 36

what are progestin contraceptives for dogs and associated outcomes?

Answer 36

1. ovaban: megestrol acetate: suppresses estrus, mammary development, weight gain, adrenal suppression 2. depo provera: medroxyprogesterone acetate: weight gain, adrenal suppression, MAMMARY NEOPLASIA!

Question 37

what are progestin contraceptives for horses and associated outcomes?

Answer 37

regu mate/altrenogest: blocks secretion of LH from anterior pituitary depo provera: not effective or recommended

Question 38

how do anti progestins work

Answer 38

binds progesterone receptor and prevents action of natural progesterone, not used in animals

Question 39

how do androgens work?

Answer 39

inhibits secretion of gonadotropins thru negative feedback decreases follicular development and inhibits ovulation

Question 40

what is a type of androgen contraceptive and side effects?

Answer 40

mibolerone: decreased incidence of CEH/pyometra, clitoral hypertrophy, discharge, increased aggression

Question 41

how do GnRH agonists work?

Answer 41

higher affinity than natural GnRH, downregulates the anterior pituitary with large doses to reduce FSH and LH to prevent follicular development and ovulation = absence of cyclicity

Question 42

how do GnRH antagonists work

Answer 42

binds to GnRH receptor, biologically inactive, rapid onset, short duration, prevents synthesis/secretion of FSH/LH to inhibit ovulation

Question 43

how do GnRH toxins work

Answer 43

binds to GnRH receptor and kills cell, decreases FSH and LH

Question 44

GnRH vaccine

Answer 44

GnRH bound to larger molecule, anti GnRH antibodies bind up circulating GnRH and prevent it from acting on its receptor = prevents FSH/LH production - antibodies must wane before cyclicity returns! - works in males and females

Question 45

ZP vaccine

Answer 45

- antibodies against ZP proteins block sperm binding site to inhibit fertilization: this does NOT INFLUENCE OVULATION OR ESTRUS - immune mediated pathology can occur

Question 46

what would you administer to induce ovulation?

Answer 46

- GnRH or GnRH agonists: stimulate anterior pituitary release of LH to induce ovulation - LH - hCG acts like LH almost (required ovarian stimulation for ovulation) - coital stimulation

Question 47

what is superovulation

Answer 47

causes ovulation of multiple follicles

Question 48

what hormones produced by the dominant follicle cause only one follicle to ovulate?

Answer 48

inhibin and estradiol

Question 49

how could you induce superovulation?

Answer 49

administer exogenous FSH or eCG or prevent action of inhibin thru immunoneutralization to allow for the action of endogenous FSH

Question 50

what would you administer to synchronize estrus?

Answer 50

- progesterone for 10-14 days to suppress LH (act as a fake CL) - could also administer estradiol to suppress FSH - 2 prostaglandin injections 14 days apart - ovsync protocol

Question 51

pathologies of cystic ovaries

Answer 51

- dairy cows with mis-timed LH surge or insufficient estrogen production by follicle - failure to ovulate, partial luteinization, persistent estrus - masculinized, persistent estrus/anestrus, elevated tail head, CEH, vulva enlargement - luteinization of cyst from hCG/gNRH or luteolysis via PGF

Question 52

if you have an animal who appears to be short cycling what might this indicate?

Answer 52

uterine infection or endometritis causing persistent release of PGF and CL lysis

Question 53

what are some causes of pseudopregnancy?

Answer 53

- inadequate PGF release, embryonic loss after maternal recognition of pregnancy, severe uterine pathology preventing release of PGF

Question 54

how might acute infection alter PGF? chronic?

Answer 54

acute: causes PGF release chronic: inhibits PGF release

Question 55

what happens in a cow that has ingested too much fescue?

Answer 55

high dopamine, low prolactin, no milk production

Question 56

what may happen when cows/ewes ingest large amounts of phytoestrogens?

Answer 56

CEH

Question 57

can you tell systemically if an animal has a uterine infection?

Answer 57

large: no small: yes

Question 58

what stage of the estrus cycle does a pyometra occur in a dog?

Answer 58

diestrus