Serum antibody titres of different immunization groups.

<p>Mean titres of (A) IgA, (B) IgG1 and (C) IgG2 of EspA-, Intimin-, Tir- and H7 flagellin (H7)-specific antibodies within the serum of calves 2 days prior to the first immunization (Pre) and 6 days after the final immunization (Post) with either EspA, intimin and Tir (<i>E-I-T</i>), EspA and intimin (<i>E-I</i>), EspA, intimin and H7 flagellin (<i>E-I-H7</i>), or adjuvant alone (Control). Each bar represents the mean (on log₁₀ scale) and corresponding error bar shows the standard error of mean. Overall statistical significance of immunization group for each antibody titre post-immunization was assessed using a linear mixed model and indicated by a <i>p</i>-value below each graph. The mean difference in titres between pre- and post-immunization for each immunization group was investigated using a linear mixed model, and statistically significant (adjusted for false discovery rate, <i>p</i>_<i>f</i> < 0.05) changes are indicated by an asterisk (*).