Oestrous Cycle Flashcards
When does a dog reach puberty and how many cycles per year?
7-12 months old.
Have 1-3 cycles per year.
Describe the stages of the oestrous cycle in the bitch and what you would look for, what hormone is dominant at each stage.
Pro-oestrous - Vulva swelling, blood, attractive to males, 5-9 days
Oestrous - Allows mating, 6-12 days
Dioestrous - Progesterone dominant hormone
Anoestrous - Resting period. Low progesterone.
Why are mating dates so unreliable?
Sperm can stay in the uterus for 7 days when mating.
What is the major indicative sign of day 4 of oocytes?
Drop in superficial cells by 20%
What does oestrogen do in the cycle?
Oedema - vulva swell and thickening.
Makes all tissue thick, full and oedematous.
What is the purpose of progesterone in the oestrous cycle?
Develops endometrial glands, closes the cervix, cause no uterus contractility and uterus immunosuppression.
Describe the oestrous cycle of the queen.
Induced ovulators
Seasonal polyoestrous
When not mated they have continuous waves of oestrogen
How is vaginal turgidity a good indicator of monitoring the oestrous cycle?
Goes turgid during pro-oestrous
Doughy during oestrous
What are some methods of monitoring the bitches oestrous cycle?
Vaginal turgidity Reflexes (perineal area) Behaviour Vaginoscopy Vaginal cytology
Will you use lubricant when doing vaginoscopy?
No!
On vaginoscopy what will you see in every stage of the oestrous cycle?
Pro-oestrous - swollen pink moist folds
Oestrous - oedema subsides, pale-pink, dry
Dioestrous - small pink round folds, foul brown discharge, rosey shaped.
At what stage of the cycle do you want to breed?
Late oestrous
When folds are small angular pale and dry
Why do we use vaginal cytology?
See when bitch is in oestrous and tell us when D1 is.
What do superficial cells indicate?
Determine the stage of oestrous cycle.
Superficial cells indicate there has been oestrogen (thickening and loss of blood supply killing the cells)
Describe how the following cell types look:
a) Superficial cells
b) Intermediate cells
c) Parabasal cells
d) Basal cells
a) dead, cornified, large & angular
b) good nucleus, partly angular
c) like intermediate but smaller and rounder
d) smaller and darker than parabasals
