Lethality of embryos inoculated with Y. enterocolitica strains ( flhD and fliA mutants). The ELA was performed with Y. enterocolitica 8081v, as well as with the flhD and fliA mutants in 8081v. Control groups of embryos were either uninoculated or inoculated with PBS. Embryos were inoculated with 108 CFU of the Y. enterocolitica strains. Lethality of the infected embryos was determined for five consecutive days. The experiment was performed three times. Panel A combines the number of dead embryos across the three experiments for each inoculum. Data are expressed as percentage of the total number of embryos for that inoculum. White capital letters in the Y. enterocolitica data bars represent the different groups from the Duncan's multiple group comparison. Panel B shows the bacterial counts in the allantoic fluid for dead (dark bars) and live embryos (light bars). Data are expressed as mean over the three replicate experiments and error bars indicate 1 s.