Strain designations are coded as follows: species/subspecies name_strain name_MLST clonal complex_pathotype. Abbreviations: Cjj, Camplyobacter jejuni subsp. jejuni; Cjd, Camplyobacter jejuni subsp. doylei; Cj, Camplyobacter jejuni, no subspecies indicated; NC, no colonization; C, colonization with no enteritis; E, colonization with enteritis; HE, colonization with hemorrhagic enteritis; CN, colonization with neurological signs but no enteritis; EN, colonization with enteritis and neurological signs; HEN, colonization with hemorrhagic enteritis and neurological signs. Pathotypes of C. jejuni strains 33560T, D0121, D0835, D2586, D2600, and NW were derived from passage 1 data in a previous serial passage study reported by Bell et al. [17]. Maximum likelihood tree generated using utilities at (http://www.phylogeny.fr/; [23]. Bootstrap support values (% of 1000 runs) are shown for major nodes; tree rooted with C. coli strain 12526.