Fig. 5.

Distribution of cumulative IgG ELISA sample-to-positive (S/P) ratios in serum samples collected from diarrheic pigs at commercial pig farms. Various indirect ELISA assays based on PEDV whole virus (WV) (A), S1 (B), ORF3C (C), and E proteins (D) were used to test serum samples from commercial sows and pigs with diarrhea at different ages with unknown PEDV infectious status. Sera from naïve piglets were used as negative controls; samples above the determined S/P cutoff (dashed line) were considered positive. One-way analysis of variance (ANOVA) was used for multiple comparisons between different ages among the individual antigens with an alpha value of 0.01. The “ns” denoted no statistical differences.