Kirchner, MargaretMiller, William G.Osborne, Jason A.Badgley, Brian D.Neidermeyer, JeffreyKathariou, Sophia2023-01-202023-01-202023-01-19Kirchner, M.; Miller, W.G.; Osborne, J.A.; Badgley, B.; Neidermeyer, J.; Kathariou, S. Campylobacter Colonization and Diversity in Young Turkeys in the Context of Gastrointestinal Distress and Antimicrobial Treatment. Microorganisms 2023, 11, 252.http://hdl.handle.net/10919/113318Young turkeys are vulnerable to undifferentiated gastrointestinal distress, including &ldquo;irritable and crabby syndrome&rdquo; (ICS), which compromises flock performance and is typically treated with a combination of penicillin and gentamicin (P/G). However, the effects of ICS and P/G treatment on <i>Campylobacter</i> remain poorly understood. We investigated the impact of ICS and P/G treatment on <i>Campylobacter</i> levels and diversity in four flocks from three turkey farms. Cecum and jejunum samples were analyzed weekly from day of hatch to week 4&ndash;5. All four flocks became colonized with multidrug resistant (MDR) <i>Campylobacter jejuni</i> and <i>C. coli</i> by week 2&ndash;3, and two developed ICS. ICS and P/G treatment did not significantly impact total <i>Campylobacter</i> levels or strain genotypes but impacted species and antimicrobial resistance (AMR) profiles. One flock was raised under antibiotic-free (ABF) conditions while another flock at the same farm was raised conventionally. The ABF flock did not develop ICS while its counterpart did. However, <i>Campylobacter</i> strains, AMR profiles and sequence types were generally shared between these two flocks. Our findings suggest that ICS and P/G treatment impacted <i>Campylobacter</i> population dynamics in commercial young turkey flocks, and that ABF flocks may become readily colonized by MDR strains from non-ABF flocks at the same farm.application/pdfenCreative Commons Attribution 4.0 InternationalturkeysCampylobacterantimicrobial resistancemultidrug resistanceirritable and crabby syndromeCampylobacter Colonization and Diversity in Young Turkeys in the Context of Gastrointestinal Distress and Antimicrobial TreatmentArticle - Refereed2023-01-20Microorganismshttps://doi.org/10.3390/microorganisms11020252