ANSC 4045 Exam 2 Study Guide || solved correctly.
Define estrous cycle. correct answers series of reproductive events starting with estrus (heat) and
ending with subsequent estrus
What is the difference between estrus and estrous? correct answers Estrus is a noun. The cow is
displaying estrus
Estrous is an adjective. The length of the estrous cycle is 21 days.
What are the three types of estrous cyclicity? correct answers polyestrus
seasonal polyestrus (long day)
seasonal polyestrus (short day)
monoestrus
What are the two major phases of the estrous cycle? correct answers follicular
luteal
List each stage of the estrous cycle and describe what happens during each stage. correct answers
pro estrus- Formation of ovulatory follicles, E2 secretion
estrus- Sexual receptivity. Peak E2 secretion
metestrus- CL formation. Beginning of P4 secretion
diestrus- Sustained luteal secretion of P4
,What defines the start of the estrous cycle? correct answers ovulation/estrus
Cow estrous correct answers polyestrus
length- 21d
duration- 15h
time from onset of estrus to ovulation- 24-32h
time from LH surge to ovulation- 28h
ewe estrous correct answers seasonally polyestrus
length- 17d
duration- 30h
time from onset of estrus to ovulation- 24-30h
time from LH surge to ovulation- 26h
Mare estrous correct answers seasonally polyestrus
length- 21d
duration- 7d
, time from onset of estrus to ovulation- 5d
time from LH surge to ovulation- 2d
Sow estrous correct answers polyestrus
length- 21d
duration- 50h
time from onset of estrus to ovulation- 36-44h
time from LH surge to ovulation- 40h
Define anestrus. correct answers Condition when the female does not exhibit estrous cycles
What are some factors that cause anestrus? correct answers Pregnancy, lactation, presence of
offspring, season
What causes a silent ovulation and when does it happen? correct answers After a period of
anestrous (seasonal or gestation)
Follicles develop secrete E2 but there will be no behavioral estrus (Silent Ovulation)
What stimulus causes secretion of melatonin? correct answers Light sensed through by eyes to
optic nerve
Through brain to pineal gland. Secretion of melatonin
Define estrous cycle. correct answers series of reproductive events starting with estrus (heat) and
ending with subsequent estrus
What is the difference between estrus and estrous? correct answers Estrus is a noun. The cow is
displaying estrus
Estrous is an adjective. The length of the estrous cycle is 21 days.
What are the three types of estrous cyclicity? correct answers polyestrus
seasonal polyestrus (long day)
seasonal polyestrus (short day)
monoestrus
What are the two major phases of the estrous cycle? correct answers follicular
luteal
List each stage of the estrous cycle and describe what happens during each stage. correct answers
pro estrus- Formation of ovulatory follicles, E2 secretion
estrus- Sexual receptivity. Peak E2 secretion
metestrus- CL formation. Beginning of P4 secretion
diestrus- Sustained luteal secretion of P4
,What defines the start of the estrous cycle? correct answers ovulation/estrus
Cow estrous correct answers polyestrus
length- 21d
duration- 15h
time from onset of estrus to ovulation- 24-32h
time from LH surge to ovulation- 28h
ewe estrous correct answers seasonally polyestrus
length- 17d
duration- 30h
time from onset of estrus to ovulation- 24-30h
time from LH surge to ovulation- 26h
Mare estrous correct answers seasonally polyestrus
length- 21d
duration- 7d
, time from onset of estrus to ovulation- 5d
time from LH surge to ovulation- 2d
Sow estrous correct answers polyestrus
length- 21d
duration- 50h
time from onset of estrus to ovulation- 36-44h
time from LH surge to ovulation- 40h
Define anestrus. correct answers Condition when the female does not exhibit estrous cycles
What are some factors that cause anestrus? correct answers Pregnancy, lactation, presence of
offspring, season
What causes a silent ovulation and when does it happen? correct answers After a period of
anestrous (seasonal or gestation)
Follicles develop secrete E2 but there will be no behavioral estrus (Silent Ovulation)
What stimulus causes secretion of melatonin? correct answers Light sensed through by eyes to
optic nerve
Through brain to pineal gland. Secretion of melatonin
