Lecture 4: Canine Ovulation Timing & Breeding Management (Kelleman) Flashcards
most common cause of infertility**
breeding at the wrong time
The Old Way of breeding dogs
breed EOD as long as bitch will stand.
- most effective non-timed method
- works for fresh semen, but not as well for cooled or frozen semen
- some bitches won’t stand or stand at wrong time
how long does fresh semen live**
7-9d
dogs have what type of sperm deposition?**
intrauterine
3 stages of breeding in dogs
1) first stage coitus
2) the turn
3) second stage coitus
bitch
intact female
dog
intact (stud) dog
what does “heat” or “in season” mean
estrus + proestrus
-time when vulvar discharge seen
canine estrous cycle
proestrus -> estrus ->diestrus ->anestrus
What does leutinizing hormone (LH) do?***
causes ovulation
progesterone produced by:**
pregnant AND non-pregnant bitches
estrogen controls:
- vaginal lining epithelial cells & wall thickness
- behavioral and physical signs
when does LH peak occur?
On day 0. Marks the end of proestrus and beginning of estrus.
Describe what estrogen, progesterone, FSH, and LH are doing during proestrus
(see slide 9)
- Estrogen rising and peaking
- Progesterone negligible, then starts to rise at very end of proestrus
- FSH declining, then sharply rises at end of proestrus
- LH low, then peaks at end
Describe what estrogen, progesterone, FSH, and LH are doing during estrus
- Estrogen declining
- Progesterone rising
- FSH peaks early then rapidly declines
- LH declining off peak
Describe what estrogen, progesterone, and LH are doing during diestrus
- estrogen declining
- progesterone peaks then declines
- LH low
Gold standard for timing ovulation and estrus cycle of the bitch uses:**
endocrinology
Events of canine estrous cycle can be described in terms of:
- behavior
- vaginal cytology
- endocrinology**
- anatomy
Behaviora/anatomical signs of estrus
- flagging: estrus behavior in bitch (NOT horses) in which tail goes off to side when perineum is touched
- vulvar turgidity and discharge
T/F: female dog’s urethra comes into vagina
T
first pat of female tract =
vestibule
Clicker: Which hormone is responsible for vaginal cytology cornification?**
Estrogen
Is vaginal cytology used for ovulation timing?**
NO. Gives you a basic idea of where bitch is in the estrous cycle.
- useful when used in conjunction with progesterone
- can run bioassay off it for presenceof estrogen***
cornification**
progression of epithelial cell death from tissue thickening due to estrogen
parabasal –> intermediate –> superficial–>anuclear squamous (“corn flake”)
superficial cells defining chars.
have pyknotic nuclei (condensed chromatin)
PMN =
polymorphonuclear neutrophil