IgG response to ApfA and VacJ proteins. IgG response in convalescent pigs against ApfA (A) and VacJ (B) proteins. IgG response is shown as area under the curve (AUC), calculated from sera dilution curves of an ELISA assay (1:500 to 1:1 093 500 dilutions) against 100 ng/well of protein. Data sets were transformed to log10 and submitted to D’Agostino & Pearson omnibus normality test to verify the assumption of Gaussian distribution of the data (alpha = 0.05). After conversion of the data sets to AUC units, differences between mean AUC values of each group were analyzed by Ordinary one-way ANOVA, followed by Holm-Sidak post hoc test when overall statistical significance was determined by ANOVA (P < 0.05). Asterisks indicate statistical difference between individual groups and controls by Holm-Sidak (P < 0.05).