Chromogenic in situ hybridization technique for detecting porcine circovirus 3 in lung and lymphoid tissues

Background and Aim: Porcine circovirus 3 (PCV3) was recently reported in Malaysian commercial pig population 2020 by conventional polymerase chain reaction (PCR), revealing a molecular prevalence of 17.02% the sampled domestic population. This study aims to describe chromogenic situ hybridization (ISH) technique using digoxigenin (DIG)- labeled cloned PCV3 open reading frame 1 (ORF1) fragment DNA detect localize antigen formalin-fixed, paraffin-embedded lung, lymphoid tissue specimens. Materials Methods: Since mainly detected lung tissues, we obtained specimens from these organs previous study. Digoxigenin-labeled ISH probes were designed target 69 bp region ORF1 spanning nucleotide positions (282–350). Results: Light microscopy analysis revealed that staining antigens visualized within cytoplasm pneumocytes lymphocytes, indicating positive results. The results detection PCR showed high agreement 90.91%, including for negative status all samples. Conclusion: reports DIG-labeled targeting tissues. Despite limited availability antibodies, remains relevant investigating replication pathogenesis can be used complementarily with evaluating localization infected Keywords: hybridization, porcine type 3, circoviruses, pigs.