Cecere

Question 1

Interestrus Interval (IEI) of the Bitch Estrous Cycle

Answer 1

Period b/w outwardly apparent heat cycles
- consists of diestrus & anestrus
- minimum = 4 months, maximum = 12 months

Question 2

Proestrus in bitches
- dominant hormone
- physical effects
- behavioral effects

Answer 2

• Estrogen
• vulvular swelling, hemorrhagic vulvular discharge
• Non-acceptance of male dog (early = growling, snapping, aggression -> late = passive: tail-tucking, sitting when male attempts mounting)

Question 3

Estrus in bitches
- dominant hormone
- behavioral effects

Answer 3

• Standing behavior
• Peak LH & FSH @ beginning => ovulation
• P4 rises, E2 falls

Estrus = “stands to be mounted”

Question 4

Diestrus in bitches
- dominant hormone
- secondary hormone
- physical effects
- behavioral effects

Answer 4

• 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

Question 5

How do queens ovulate?

Answer 5

They are induced (chemically or are bred)

Are Seasonally Polyestrous (20% still cycle year-round)

Purebred cats cycle more like dogs

Question 6

Dominant hormone of diestrus in the queen

Answer 6

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.