Supporting Information Available The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.jproteome.0c00592.Supplementary Figure S1: Repeatability analysis of different biological replicates used for iTRAQ-coupled LC–MS/MS proteomic analysis; Supplementary Figure S2: The original images of the entire PVDF membranes containing the target Western blots of Figure 2C (PDF) Supplementary File S1: A total of 5502 proteins identified in PDCoV- and mock-infected IPEC-J2 cells using iTRAQ-coupled LC-MS method (XLSX) Supplementary File S2: Viral proteins identified in PDCoV-infected IPEC-J2 cells (XLSX) Supplementary File S3: GO function annotation of the 78 differentially expressed proteins (XLSX) Supplementary File S4: COG function classification of the 78 differentially expressed proteins (XLSX) Supplementary File S5: KEGG pathway analysis of the 78 differentially expressed proteins (XLSX) Supplementary File S6: The top 20 KEGG pathway of the 23 significantly upregulated proteins (XLSX) Supplementary File S7: The top 20 KEGG pathway of the 55 significantly downregulated proteins (XLSX)