Ruminant/Porcine Estrous Cycles

Question 1

FSH in cattle is __ producing __waves of follicles per cycle

Answer 1

cyclic, 2-3

Question 2

the LH surge in cattle __ ovulation

Answer 2

induces

Question 3

estrogen produces what behavior in cattle?

Answer 3

standing behavior

Question 4

progesterone is high in the __ phase

Answer 4

luteal

Question 5

if a follicular wave forms when progesterone is high, what happens to the dominant follicle?

Answer 5

it undergoes atresia

Question 6

t/f: most follicles undergo atresia

Answer 6

T

Question 7

Proestrus in cattle

Answer 7

starts after luteolysis and develops a dominant follicle with estrogen being the dominant follicle. This is when the uterus starts to develop some tone

Question 8

estrus in cattle

Answer 8

LH peaks triggering ovulation to happen 27-30 hours later. During this phase estrogen is the dominant hormone and the uterus is toned

Question 9

the cardinal sign of a cow in estrus is __

Answer 9

standing to be mounted

Question 10

metestrus starts after __ and __ begins to increase, there may be __

Answer 10

ovulation, progesterone, metestral bleeding

Question 11

diestrus in the cow

Answer 11

the CH becomes the CL which produces progesterone for 8-9 days and is lysed by PGF if the cow is not pregnant

Question 12

t/f: the CL is not responsive to PGF prior to Day 5

Answer 12

T

Question 13

estrus happens for longer and is more obvious in __ than __ (small ruminants)

Answer 13

does, ewes

Question 14

in sheep/goats, during short photoperiods __stimulates the release of GnRH which initiates __ increasing FSH and LH leading to __

Answer 14

increased melatonin, cyclicity, ovulation

Question 15

swine have a __ wave of follicles in their __ day cycle with ovulation occurring __ of the way though estrus

Answer 15

single, 21, 2/3

Question 16

in swine, ovulation occurs 24 hours after the __ peak with __ follicles rupturing over a 1-4 hour period

Answer 16

LH, multiple