What is a rarely used sampling method for livestock due to its destructive nature?

• A. Sponging
• B. Excision
• C. Moving window
• D. Swabbing

Answer: (B)

Destroying tissue to obtain a sample is not compatible with routine livestock testing. Excision involves surgically removing a piece of tissue, which destroys that portion of the animal or carcass and can affect welfare, product value, and contamination risk. Because of these drawbacks, this method is rarely used in regular surveillance and is reserved for special diagnostic or research needs. In contrast, sponging and swabbing collect surface material without removing tissue, and moving window sampling is designed to sample without causing tissue removal, making them preferable for routine testing. Hence, tissue removal through excision is the rarely used, destructive sampling method.