For diagnosing porcine parvovirus, which fetal sample should be submitted for testing?

• A. Placental swab
• B. Live neonate
• C. Maternal serum
• D. Entire mummified fetus

Answer: (D)

Diagnosing porcine parvovirus hinges on finding the virus in fetal tissues, not just in the dam. PPV causes fetal death and often mummification, so the most reliable way to confirm fetal infection is to submit the entire mummified fetus. This provides intact fetal tissues for direct detection of viral DNA or antigens and for histopathology, increasing the chance to observe characteristic fetal lesions and to obtain a clear positive result.

Submitting a placental swab can be less definitive because the virus may be unevenly distributed and could reflect maternal or environmental contamination. Maternal serum shows whether the dam has been exposed but does not prove that a particular fetus was infected. A live neonate may test negative even if the dam was infected and the fetus died earlier; maternal antibodies can also complicate interpretation. Therefore, the entire mummified fetus is the best sample for confirming PPV infection in the fetus.