Figure 4.

Postvaccinate OMPs-specific antibody response in chickens vaccinated orally with OMPs-F-PNPs.

Notes: Layer chickens were inoculated orally three times at 3-week intervals with PBS (Group 1), or soluble OMPs and F-protein (Group 2), or OMPs-F-PNPs (Group 3). (A–C) OMPs-specific IgG antibody response in serum was analyzed by ELISA. Each bar is the mean ± SEM of 8–10 chickens, and the data were analyzed by nonparametric Kruskal–Wallis test followed by P-value differences in between the groups determined by Mann–Whitney test. Asterisk refers to statistical difference between the two indicated groups (^**P<0.01). OMPs-F-PNPs, OMPs and F-protein-entrapped and surface F-protein-coated PNPs.

Abbreviations: F, flagellar; OMPs, outer membrane proteins; PNPs, polyanhydride nanoparticles; SEM, standard error of the mean.