DHA and EPA inhibited PEDV in a dose-dependent manner. (A–F) PEDV, TGEV, and PDCoV were infected in vero cells, PK-15 cells, and LLC-PK1 cells, respectively; 30 µM, 50 µM, and 100 µM of DHA and EPA were added, and replication in vero cells, PK-15 cells, or LLC-PK1 cells was determined by qPCR at 12 h. (G) Replication of TGEV, PEDV, or PDCoV (MOI = 0.1) in vero cells, PK-15 cells, or LLC-PK1 cells was determined by IFA at 24 h. Cells were fixed with 4% paraformaldehyde and stained with anti-TGEV-N, anti-PEDV-N, or anti-PDCoV-N antibody and FITC-conjugated secondary antibody (green); nuclei were stained blue with DAPI. (H–I) In postinfection experiments, cells were first infected with virus for 1 h, and then DHA or EPA was added at different time points (1, 3, 5, 7, and 9 h). Cells were collected after 12 h for qRT-PCR. P values <0.05 were considered statistically significant. Bars represent standard deviations. Results were presented as mean ± SD, and the asterisks indicate significance relative to controls (Student’s t test, *P < 0.05; **P < 0.01).