Figure 1: Detection of porcine circovirus type 2 (PCV2) with PCR method. The primers designed on the basis of the ORF2 of the PCV2 virus genome to produce a 416 bp long amplicon. The BOOP lung tissues from five pigs were positive. In the agarose gel, three representative cases were shown. Neg: negative control. M: leader. Lanes 1–3: BOOP lung samples. Lanes 4–6: normal lung samples from SPF pigs ( , six replicates in each individual BOOP or normal pig).