CAS Avian Reproduction & Breeding 2 — Questions and Answers
Question 1: What is the primary environmental cue that triggers the hormonal cascade initiating reproductive behavior in most bird species?
- Increased melatonin production
- Changes in photoperiod (day length) (Correct answer)
- Ambient temperature fluctuations
- Barometric pressure changes
Correct answer: Changes in photoperiod (day length)
Photoperiod (day length) is the primary environmental cue detected by the hypothalamic-pituitary-gonadal axis to initiate reproductive activity in most birds.
Question 2: What relative humidity level is generally recommended during the first two-thirds of incubation for most parrot eggs?
- 20–30%
- 40–50% (Correct answer)
- 65–75%
- 80–90%
Correct answer: 40–50%
A relative humidity of approximately 40–50% is recommended during most of incubation to allow for the correct rate of moisture loss from the egg.
Question 3: The technique of 'double clutching' in avian breeding refers to:
- Breeding two pairs of birds in the same aviary simultaneously
- Removing the first clutch to stimulate the hen to produce a second clutch (Correct answer)
- Providing two nest boxes per breeding pair
- Cross-fostering eggs between two parent pairs
Correct answer: Removing the first clutch to stimulate the hen to produce a second clutch
Double clutching involves removing the first clutch for artificial incubation, which stimulates the hen to produce a second clutch and effectively doubles annual egg production.
Question 4: How frequently should eggs be turned during artificial incubation to support proper embryonic development?
- Once daily in the morning only
- At least 3–5 times per day (Correct answer)
- Only during the first three days
- Turning is unnecessary with forced-air incubators
Correct answer: At least 3–5 times per day
Eggs should be turned at least 3–5 times daily (ideally every 1–2 hours) to prevent embryo adhesion to shell membranes and ensure even heat distribution.
Question 5: What does the term 'lockdown' refer to during the artificial incubation process?
- Lowering temperature to slow embryo development
- Stopping egg turning and raising humidity for the final hatch period (Correct answer)
- Sealing the incubator to prevent contamination
- Temporarily cooling eggs for transport
Correct answer: Stopping egg turning and raising humidity for the final hatch period
Lockdown refers to the final 2–3 days before hatch when egg turning stops and humidity is increased to facilitate the chick's internal and external pip.
Question 6: In hand-rearing chicks, at what point should feeding stop to avoid crop stasis or aspiration?
- When the crop is visibly full and slightly firm (Correct answer)
- When food begins backing up into the esophagus
- When the chick stops vocalizing
- When the crop feels completely rigid
Correct answer: When the crop is visibly full and slightly firm
Feeding should stop when the crop is visibly full and slightly firm; overfilling can lead to crop stasis, regurgitation, or aspiration pneumonia.
Question 7: Imprinting in hand-raised birds primarily affects which of the following?
- The bird's foraging technique and food preferences
- The bird's social identity and future bonding/breeding partners (Correct answer)
- The bird's territorial vocalizations
- The bird's migration instinct
Correct answer: The bird's social identity and future bonding/breeding partners
Imprinting causes a hand-raised bird to identify humans as its own species, which can significantly affect social bonding, mate selection, and breeding success later in life.
CAS Avian Reproduction & Breeding 2
What is the primary environmental cue that triggers the hormonal cascade initiating reproductive behavior in most bird species?