Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).
Assertion (A) : Benzimidazole resistance is common in Haemonchus contortus infecting sheep and goats at organized farms in India
Reason (R) : Benzimidazole resistance is diagnosed by faecal egg count reduction test (FECRT)
In light of the above statements, choose the correct answer from the options given below.

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
• C. (A) is true but (R) is false.
• D. (A) is false but (R) is true.

Hint:

Always ask "Why?" after reading the Assertion. If the Reason answers "Why", then (R) is the correct explanation. Here: "Benzimidazole resistance is common... because it is diagnosed by FECRT." This statement does not make logical sense, meaning (R) is not the explanation.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Anthelminthic resistance occurs when a parasite population develops the ability to tolerate drug doses that are normally lethal.
This is a major challenge in small ruminant production, especially with gastrointestinal nematodes.
Detailed Explanation:
Let us analyze the statements:
- Assertion (A) analysis: Haemonchus contortus (barber's pole worm) is highly pathogenic and has developed widespread resistance to the benzimidazole group of anthelmintics on sheep and goat farms globally, including in India. This is due to frequent, repetitive, and under-dosed deworming regimes. Thus, Assertion (A) is true.
- Reason (R) analysis: The Faecal Egg Count Reduction Test (FECRT) is the standard, globally recommended in vivo diagnostic method used to evaluate and confirm anthelmintic efficacy and resistance in livestock. Thus, Reason (R) is also true.
- Evaluating the connection: While both statements are true, the reason describes the *diagnostic method* used to detect the resistance. It does *not* explain the biological or operational *reasons why* the resistance developed in the first place (which is due to selection pressure, genetic mutations, and treatment frequency). Thus, (R) is not the correct explanation of (A).

Step 2: Final Answer:
Both (A) and (R) are true, but (R) is not the correct explanation of (A). This corresponds to Option (B).