Canine Estrus Cycle Flashcards
Describe the physical changes during proestrus
- turgid swelling of vulva
- hemorrhagic vulvar discharge
Describe the proestrus vaginal cytology
early - cornified epithelial cells, parabasal and small intermediate cells
late - superficial and large intermediate cells increase
What is found on vaginal speculum during proestrus?
early - vaginal mucosa edematous
late - starts shrinking, less edema
Describe behavior during proestrus
attracts males (sex pheromones) but non-receptive
Describe the hormone profiles during proestrus
- estrogen dominates
- LH and FSH low
- progesterone low but rising
What is the average duration for proestrus?
7-9 days
Describe the physical changes during estrus
- softening of vulvar swelling
- scant blood discharge
Describe the behavior during estrus
- stands to be mounted
- tail elevated and deviated to side
- muscles around vulva contract and raise vulva
- stiffening of back legs
- rolling of skin on back
What is found on vaginal speculum during estrus?
early - shrinking of mucosa
late - max shrinkage called crenulation
Describe estrus vaginal cytology
- > 90% cornified epithelium
- no WBCs, few RBCs
Describe the hormone profiles during estrus
- estrogen begins to fall
- progesterone starts to rise
- high LH and FSH
Describe the behavior during diestrus
female begins to refuse mating
Describe diestrus vaginal cytology
- superficial cells decrease
- parabasal and small intermediate cells increase
What is found on vaginal speculum during diestrus?
- rounding/smoothing mucosa
- may see variegated red/white areas
What is the dominant hormone during diestrus?
progesterone
Describe the behavior during anestrus
no sexual interest from male or female
What is seen of vaginal speculum during anestrus?
vaginal wall is very thin and pale
Describe anestrus vaginal cytology
- few non-cornified cells
- superficial cells absent
When does LH peak?
24-48 hours into estrus
When does ovulation occur?
24-48 hours after LH surge
day 3-4 of estrus
LH surge occurs when progesterone is at what concentration?
2 ng/mL
Ovulation occurs when progesterone is at what concentration?
5 ng/mL
When should the bitch be bred naturally or with fresh semen AI?
48-72 hours after P4 concentration of 5
When should the bitch be bred with cooled/chilled semen?
72-96 hours after P4 concentration of 5
When should the bitch be bred with frozen semen?
at least 96 hours after P4 concentration of 5
What is superfecundation?
when two males breed the same female during a single estrus
What is superfetation?
where a female may be bred and pregnant, then go through another receptive period and get pregnant again
