Fig. 4.

The sensitivity of the panCoV RT-PCR assays. The RdRp genes were amplified from recombinant plasmids that subcloned the RdRp genes of PDCoV, PEDV and TGEV into the pGEM-T Easy vector. The detection limit of the panCoV RT-PCR assay was determined through 10-fold dilutions of each plasmid (from 1 × 10⁷ to 1 × 10¹ copies/μL) and amplified by panCoV RT-PCR assays. Lane M, DNA marker DL2000; Lane N: negative control; Lanes 10⁷–10¹: recombinant plasmids of PDCoV, PEDV, and TGEV with 10-fold dilutions (1 × 10⁷–1 × 10¹ copies/μL).