Figure 1

The schematic diagram of PCV2 strains of different genotypes in detail. Analysis of the ORF2 gene in PCV2b/YJ indicated a one-base deletion at position 1039 in the genome, resulting in an ORF2 gene of 708 nt. For PCV2d/BDH strain, a shift from TTA to CTT in the genomic sequence resulted in the stop codon mutation (from UAA to AAG) in the ORF2 (at the anti-sense chain of the genomic sequence of PCV2), being an ORF2 gene of 705 nt in another stop codon.