Question

Read the following statements:
A. Laying cycle includes clutch and pause
B. Frequency with which laying and pause recurs is known as laying rhythm
C. Each egg is laid little later in the successive day and the last egg is laid in the late afternoon, where the cycle is terminated.
D. Laying rhythm and cycles are fairly constant
Choose the correct answer from the options given below:

• A. A only
• B. A and B only
• C. A, B and C only
• D. A, B, C and D

Hint:

Egg formation takes about 25 to 26 hours, which explains why hens lay eggs later each day until a pause day occurs to reset the cycle.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The reproductive biology of the domestic hen involves complex hormonal and physiological cycles that coordinate ovulation and egg laying (oviposition).
These patterns are described using terms like clutch, pause, and laying rhythm.

Step 2: Detailed Explanation:
Let us analyze each statement:
- Statement A: A clutch refers to the number of eggs laid by a hen on consecutive days without interruption. A pause is the day or days of rest between clutches when no egg is laid. The laying cycle includes both of these phases. This statement is correct.
- Statement B: The regular, recurring pattern of clutches and pauses over time is called the laying rhythm. This rhythm is controlled by the bird's internal circadian clock and light-dark cycles. This statement is correct.
- Statement C: The time required to form an egg is slightly longer than 24 hours (typically around 25 to 26 hours). Because of this, a hen ovulates and lays each egg slightly later each day. Eventually, the oviposition time shifts to the late afternoon. When this occurs, the release of luteinizing hormone (LH) is blocked by the dark phase, preventing ovulation and ending that clutch. The following day is a pause day, and the cycle resets the next morning. This statement is correct.
- Statement D: Laying rhythms and cycles are not constant. They vary based on the age of the hen, environmental light patterns, nutrition, and genetic strain. Young, high-producing hens have long clutches and short pauses, while older hens have shorter clutches and longer pauses. This statement is incorrect.

Step 3: Final Answer:
The correct statements are A, B, and C only.