Cecere Flashcards
Interestrus Interval (IEI) of the Bitch Estrous Cycle
Period b/w outwardly apparent heat cycles
- consists of diestrus & anestrus
- minimum = 4 months, maximum = 12 months
Proestrus in bitches
- dominant hormone
- physical effects
- behavioral effects
- Estrogen
- vulvular swelling, hemorrhagic vulvular discharge
- Non-acceptance of male dog (early = growling, snapping, aggression -> late = passive: tail-tucking, sitting when male attempts mounting)
Estrus in bitches
- dominant hormone
- behavioral effects
- Standing behavior
- Peak LH & FSH @ beginning => ovulation
- P4 rises, E2 falls
Estrus = “stands to be mounted”
Diestrus in bitches
- dominant hormone
- secondary hormone
- physical effects
- behavioral effects
- Progesterone (P4), pekas 25-35 days post ovulation
- Prolactin = 2º hormone = luteolytic
- vulvar swelling disappears; scant purulent discharge dissipates
- begins w/ non-acceptance of male
- pseudopregnancy = normal in the bitch
How do queens ovulate?
They are induced (chemically or are bred)
Are Seasonally Polyestrous (20% still cycle year-round)
Purebred cats cycle more like dogs
Dominant hormone of diestrus in the queen
Progesterone
- only occurs when ovulation has been induced by breeding, hormonal or mechanical means
If the queen ovulates, corpora lutea are formed and secrete progesterone. Elevated progesterone levels are the hallmark of diestrus.
If the queen is not pregnant, diestrus is also termed pseudopregnancy and lasts for 35 to 40 days.
