Non-surgical Control of Reproduction Flashcards
where is GnRH produced?
hypothalamus
Pulsatile secretion of ______ causes gonadotropin secretion (FSH, LH)
GnRH
What hormone is dominant in the follicular phase to allow for follicular growth?
FSH
Which hormone is key for dominant follicles and surges just prior to ovulation in dogs/cats?
LH
__________ has negative feedback on the hypothalamus and pituitary and increases as a result of growing follicles.
estradiol
If estradiol has negative feedback on the hypothalamus and the pituitary, what hormones does this down-regulate?
GnRH, FSH, LH.
Which hormone is dominant during the luteal phase?
progesterone
which hormone is luteotrophic and involved with lactation?
prolactin
Estradiol is the hormone produced by the ovaries. When does estradiol peak in the canine cycle?
Estradiol is produced by the ovaries during proestrus and PEAKS ~1-2 days before estrus.
proestrus lasts ~6-11 days
What hormone elevation marks the start of estrus in the dog?
LH
This is caused by decreased estrogen and increasing progesterone.
When does progesterone peak in reference to ovulation?
2-3 weeks AFTER ovulation.
T/F: anestrus is the stage of the canine cycle that occurs either at the end of the heat cycle or after having a litter of puppies
true
progesterone remains low
uterus undergoes involution
Estrus control is NOT considered a good non-surgical population control option for which of the following scenarios?
A. when needing irreversible results
B. breeding animals
C. high-risk surgical or anesthetic candidates
D. risks involved with pursuing surgery
A. when needing irreversible results
this is a reversible type of non-surgical control.
Which of the following is FALSE about Megestrol Acetate (MGA)?
A. MGA is a progestin
B. MGA has temporary effects
C. MGA comes in oral or injectable forms
D. MGA blocks the production and release of GnRH
E. MGA upregulates LH surge
E. MGA upregulates LH surge
inhibits the LH surge as a result of blocking the production/relase of GnRH
What is the MAIN use of Megestrol Acetate (MGA)?
suppress or prevent cycling for 4-6 months.
State for each stage of the canine cycle when you should administer Megestrol Acetate (MGA) if you are desiring to suppress cycling for 4-6 months?
In anestrus:
In proestrus:
In anestrus: 1 week prior to expected proestrus
In proestrus: within the first 3 days of proestrus
T/F: when giving MGA during proestrus, the bitch will still be attractive to males until her clinical signs resolve
true
Which of the following is NOT a contraindication for the use of progestins?
A. prior to pubertal heat
B. use for 2+ consecutive cycles
C. if repro tissue disease is present
D. if animal needs to have the ability to get pregnant in the future
E. if older bitch
F. if bitch has liver disease
D. if animal needs to have the ability to get pregnant in the future
you should NOT give these drugs prior to pubertal heat because they can force puberty before the bitch is ready. Using progestins for more than 2+ consecutive cycles increases pyometra risks and other uterine pathology.
Name 6 risks associated with progestin use
- uterine pathology
- mammary tumors
- metabolic and growth hormone??
- acromegaly
- adrenal suppression
- break through estrus signs
T/F: there is a high risk for pyometra when using progestins, despite the dose.
false – low risk when used at recommended dose in anestrus