When submitting laboratory samples for a systemic disease in pigs, what tissue should always be included for classical swine fever surveillance?

When submitting laboratory samples for a systemic disease in pigs, what tissue should always be included for classical swine fever surveillance?

• A. Brain
• B. Tonsil
• C. Liver
• D. Spleen

Answer: (B)

Tonsil tissue is the best choice for classical swine fever surveillance because the virus replicates extensively in lymphoid tissues and is shed from the tonsils, often persisting there longer and at higher levels than in other organs. This makes tonsil samples the most sensitive for detection by methods like PCR or virus isolation, even in subclinical or later-stage infections. While brain, liver, and spleen can be affected, they are less consistently positive for CSF, so including the tonsil greatly improves the chance of identifying infected pigs.

Tonsil tissue is the best choice for classical swine fever surveillance because the virus replicates extensively in lymphoid tissues and is shed from the tonsils, often persisting there longer and at higher levels than in other organs. This makes tonsil samples the most sensitive for detection by methods like PCR or virus isolation, even in subclinical or later-stage infections. While brain, liver, and spleen can be affected, they are less consistently positive for CSF, so including the tonsil greatly improves the chance of identifying infected pigs.