ANSC 4402 EXAM QUESTIONS AND ANSWERS A+
GRADED
What is estrogen produced by?
follicles
What are the 3 hormones produced by the ovaries?
Estrogen, progesterone, relaxin
What's the difference between estrous and estrus?
Estrous is the 21 day in length, and estrus is when mare is In heat about 6 days.
Describe A transitional mare
When a mare is coming out of anestrus (winter) and when ovaries start working again
What is the term of mares having no cycles in the winter?
Mares are seasonally polyestrous
Since mares are seasonally polyestrous - corresponds to day length - when do
you expose them to light ?
No later than thanksgiving
What does increased light do for the mares? Explain
Increased light Will decrease melatonin from pineal gland, when it decreases then gnrh
is released which
Then FSH is released _ once FSH is released then ovaries develop follicles and start
cycling again
What are signs of heat name 3
Frequent urination, labia winking, squatting and backing up toward stallion, moody,
irritable mares
Why are twins not popular or desired?
Because they are hard to keep healthy all usually will have health problems
What hormone is responsible for final follicular maturation and ovulation
LH
Is the length of estrus the same for every mare?
No because estrus last 3-7 days
When does ovulation occur?
24-48 hrs prior to end of estrus
When do you want to breed? Like the best time
36 hrs prior to ovulation
Explain how CL becomes CL
Corpus hemorrhagicum is formed from cavities left by ovulating follicles which form
blood clot - then luteinizes and becomes CL
What's another term for diestrus?
luteal phase
What hormone does the CL produce?
Progesterone
If a mare is not pregnant - after 14 days the endometrium secretes prostaglandin
which causes a destruction in what ?
GRADED
What is estrogen produced by?
follicles
What are the 3 hormones produced by the ovaries?
Estrogen, progesterone, relaxin
What's the difference between estrous and estrus?
Estrous is the 21 day in length, and estrus is when mare is In heat about 6 days.
Describe A transitional mare
When a mare is coming out of anestrus (winter) and when ovaries start working again
What is the term of mares having no cycles in the winter?
Mares are seasonally polyestrous
Since mares are seasonally polyestrous - corresponds to day length - when do
you expose them to light ?
No later than thanksgiving
What does increased light do for the mares? Explain
Increased light Will decrease melatonin from pineal gland, when it decreases then gnrh
is released which
Then FSH is released _ once FSH is released then ovaries develop follicles and start
cycling again
What are signs of heat name 3
Frequent urination, labia winking, squatting and backing up toward stallion, moody,
irritable mares
Why are twins not popular or desired?
Because they are hard to keep healthy all usually will have health problems
What hormone is responsible for final follicular maturation and ovulation
LH
Is the length of estrus the same for every mare?
No because estrus last 3-7 days
When does ovulation occur?
24-48 hrs prior to end of estrus
When do you want to breed? Like the best time
36 hrs prior to ovulation
Explain how CL becomes CL
Corpus hemorrhagicum is formed from cavities left by ovulating follicles which form
blood clot - then luteinizes and becomes CL
What's another term for diestrus?
luteal phase
What hormone does the CL produce?
Progesterone
If a mare is not pregnant - after 14 days the endometrium secretes prostaglandin
which causes a destruction in what ?
