Female Fertility Flashcards
(27 cards)
What is oestrus?
Time when the female becomes sexually receptive to the male
Vary in lengths and intensity
Timing of ovulation varies between species
Oestrus in the mare
4-8 days
Ovulate 1-3 days before end of oestrus
Seasonally polyoestrus (long day breeders)
Oestrus in Cow
5-18 hours
Ovulate 12 hours from end of oestrus
Polyoestrus
Oestrus in ewe
24-36 hours
Ovulate 30-36 hours from onset of oestrus
Sesonal polyoestrus (short day breeders)
Oestrus in Queen
7-10 days
Induced ovulators
Need sufficient stimulation to reach threshold for LH surge to induce ovulation
Seasonal polyoestrus
Oestrus in bitch
7-14 days
Variable time of ovulation
Often 2 days after onset of standing oestrus
When does oestrus occur?
- Once a animal has reached sexual maturity - after puberty has been initiated
- After parturition/lactational anoestrus
- After seasonal anoestrus
Occurs in latter part of follicular phase
Driven by increasing oestradiol conentrations
* Required prior fall in progesterone
* LH surge occurs prior to ovulation
Considerations in females for optimal time to mate
- Period of pre-ovulatory follicle growth maturation
- Increasing oestradiol that induces oestrus and LH surge
- Oocytes in most species are short lived so need to be mated around ovulation
- Can synchronise ovulation - artificial insemination
Fertilisation Period
- When oocytes are available to be fertilised by sperm
* Usually immediately after ovulation - Within fertile period
Fertile period
- Time when mating could result in pregnancy
- Longer than fertilisation period - sperm can last within female reproductive tract
Progesterone concentrations in Oestrus cycle
- Decreases during luteolysis which precedes follicular phase
- Fall indicates that oestrus will occur soon - needs to be low for oestrus
- In dogs - increase in progesterone indicates lutenisation and therefore ovulation is imminent
Oestradiol concentrations in Oestrus cycle
- Elevated during follicular phase
- Often similar to oestrus profile
GnRH concentrations in Oestrus cycle
- Surge triggered prior to ovulation - triggers LH surge
- Short lived
LH concentrations in Oestrus cycle
- LH surge at end of follicular phase triggers ovulation
In what animals can you transrectally ultrasound ovaries?
Mare
Cow
What does presence of a CL mean?
Ovulation has occurred
Progesterone will be high
Ovulation can no longer occur
In luteal phase
What does an antral follicle look like?
Black - anechoic (fluid filled)
* Cow - 10mm at least
* Mare - 30-50mm
Likely to be multiple - one will be largest - dominant will ovulate
Oestrogen dominated Uterus Tonicity Mare
Late follicular phase/ during oestrus
Broad and soft cervix
Uterus is large and oedematous
Oestrogen dominated Uterus Tonicity Cow
Late follicular phase/ during oestrus
Narrow and tense cervix
Uterus is oedematous with increased tone
Progesterone dominated Uterus Tonicity Mare
After Ovulation - presence of CL
Hard and narrow cervix
Uterus is smaller with increased tone
Progesterone dominated Uterus Tonicity Cow
After Ovulation - presence of CL
Flaccid and soft cervix
Flaccid and reduced tone of uterus
Anoestrus Canine Vaginal Cytology
++ Parabasal cells (look like eggs)
+ Small intermediate epithelial cells
+ Neutrophils
Early Proestrus Canine Vaginal Cytology
+++ Parabasal cells
+++ Small intermediate epithelial cells
+ Erythrocytes
+ Neutrophils
Late Proestrus Canine Vaginal Cytology
+ Parabasal cells
++ Small intermediate epithelial cells
++ Large intermediate epithelial cells
++ Keratinised anuclear cells
+++ Erythrocytes
