Antibody production in immunized and challenged chickens.

<p>Panel A, anti-LPS antibodies after oral vaccination and oral challenge on day 42 of the chicken’s life. Panel B, the same as in panel A except for the data shown for anti-flagellin antibodies. Panel C, anti LPS antibodies after oral vaccination and i.v. revaccination followed by oral challenge on day 63 of the chicken’s life. Panel D, the same as in panel C except for the data shown for anti-flagellin antibodies. As competitive ELISA was used, the increase in anti-flagellin antibody is characterized by a decrease in absorbance. Diamonds, SPI1-<i>lon</i>::Cm vaccinated chickens; squares, SPI1- <i>lon</i>::Cm-<i>fliC</i> vaccinated chickens; triangles, SPI1- <i>lon</i>::Cm-<i>fliC</i>-<i>rcsB</i>::Kan vaccinated chickens; circles, non-vaccinated chickens. * - significantly different from the non-infected controls sacrificed on day 42 by Kruskal-Wallis and post hoc Dunn’s test at P<0.05 (panels A and B) or day 46 (panels C and D).