Which NSAID is discouraged for off-label use in cattle due to its long withdrawal time and zero residue tolerance?

• A. Meloxicam
• B. Ketoprofen
• C. Phenylbutazone
• D. Aspirin

Answer: (C)

Phenylbutazone is an NSAID that is specifically discouraged for off-label use in cattle because it has a long withdrawal time and a zero tolerance for drug residues in food-producing animals. This means that if phenylbutazone is used in cattle, the meat or milk produced will not be safe for human consumption as it may contain residues that exceed acceptable limits.

In the context of food animal production, the presence of drug residues in animal products can pose significant health risks to consumers, leading to strict regulations about which medications can be used and under what circumstances. Phenylbutazone is associated with potential adverse effects such as agranulocytosis and has been banned in many jurisdictions for use in food animals primarily to safeguard public health.

Other NSAIDs listed either have established withdrawal periods or are deemed safe for use in cattle under certain conditions, making them more appropriate choices for managing pain and inflammation in these animals.