Quantification of PEDV-specific IgA and IgG antibody titers in clinical samples of PEDV infected sows. Samples were collected from the uninfected and post PEDV-infected sows as indicated in the Table 1. PEDV specific IgA (A–E) and IgG (F–J) antibody titers were quantified by ELISA, with plates coated either using PEDV whole virus-derived antigen (A–C and F–H), S protein (D, I) or M protein (E, J); in plasma (A, D–F, I, J), oral fluid (B, D, E, G, I, J), and fecal (C–E and H–J) samples. Each bar represents mean OD450 value ± SEM from six sows. Lowercase alphabet indicates statistically significant difference between uninfected and PEDV-infected corresponding parity sow groups, and asterisk indicates statistical difference between the indicated PEDV-infected sow groups (“a” or *P < 0.05, “b” or **P < 0.01 and “c” or ***P < 0.001).