Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).
Assertion (A): Anticholinergic drugs are not commonly used as antisialogogue in ruminants.
Reason (R): Administration of anticholinergic agents make the salivary secretions of ruminants thick and viscid, and thus predisposes them to airway obstruction.
In light of the above statements, choose the most appropriate answer from the options given below.

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

Hint:

Instead of using atropine to control saliva in ruminants, the standard clinical practice is to intubate the trachea rapidly and position the animal in lateral recumbency with the head lower than the neck to allow saliva to drain out of the mouth freely.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Salivation in ruminants is continuous and voluminous, playing an essential role in buffering the rumen.
Anticholinergic drugs like atropine reduce salivary flow in monogastric animals but have undesirable and dangerous consequences in ruminants.

Step 2: Detailed Explanation:
Let us analyze Assertion (A):
Anticholinergic drugs (such as atropine) are indeed not recommended or commonly used as antisialogogues in ruminants prior to general anesthesia. (True)
Let us analyze Reason (R):
Ruminants secrete massive amounts of saliva.
Administering an anticholinergic does not completely stop salivation, but rather alters the composition of the saliva.
It selectively reduces the water content of the secretions, making the remaining saliva highly thick, viscous, and ropy.
This thick, sticky mucus cannot be easily swallowed or cleared and tends to accumulate in the pharynx and larynx, predisposing the anesthetized ruminant to life-threatening airway obstruction.
Therefore, Reason (R) is correct and provides the direct physiological explanation for Assertion (A).

Step 3: Final Answer:
Both (A) and (R) are correct, and (R) is the correct explanation of (A).