Question

Find the correct answer based on the following statements:
Statement (I): In sheep and goats, 1-8 corpus luteum are formed following ovulation depending upon breed and plane of nutrition.
Statement (II): In cows and buffaloes following ovulation, the corpus luteum attains maximum size on day 11-12 of the cycle.

• A. Both Statement (I) and Statement (II) are correct.
• B. Both Statement (I) and Statement (II) are incorrect.
• C. Statement (I) is correct but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

The ovulation rate in small ruminants (sheep and goats) can be increased by "flushing," which is the practice of providing extra feed/nutrition 2-3 weeks before mating.
In cattle, the corpus luteum is fully functional and mature during mid-diestrus (days 11-12).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The corpus luteum (CL) is a temporary endocrine structure formed from the mature ovarian follicle after ovulation.
It plays a critical role in the estrous cycle by secreting progesterone, which prepares the uterus for pregnancy.
The number of corpora lutea formed depends on the ovulation rate, which varies significantly among different livestock species.

Step 2: Detailed Explanation:
Let us analyze both statements in detail:
Statement (I): Sheep and goats are polytocous (or multitocous) species, meaning they regularly ovulate more than one oocyte during each estrous cycle.
The exact number of ovulations, and consequently the number of corpora lutea formed (ranging from 1 to 8), is highly variable.
This number is strongly influenced by the specific breed (e.g., highly prolific breeds like Garole in sheep or Black Bengal in goats) and the plane of nutrition (such as flushing, which involves feeding high-energy diets before breeding to increase ovulation rate).
Therefore, Statement (I) is correct.
Statement (II): Cows and buffaloes are monotocous species that typically ovulate a single follicle per cycle.
Following ovulation, the ruptured follicle undergoes luteinization to form the corpus luteum.
In these species, which have a standard estrous cycle of about 21 days, the corpus luteum grows progressively and reaches its maximum physical size and secretory capacity (peak progesterone levels) during the mid-luteal phase, specifically on days 11 to 12 of the cycle.
Therefore, Statement (II) is correct.
Since both statements are correct, option (A) is the correct choice.

Step 3: Final Answer:
Both Statement (I) and Statement (II) are correct.