Convergence of the turkey gut microbiota following cohabitation under commercial settings

Background: Microbiota development is a critical aspect of turkey poult maturation, and the succession of microbes in the turkey gut has been shown to correlate with poult performance. The purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing birds. Turkey poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood system. After 11 days of growth, hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 days. Sampling of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study, and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon sequencing. Results: Alpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move, but the difference between systems was not observed post-move. Using beta diversity metrics, bacterial community succession appeared delayed in the hatch brood system birds pre-move, but post-move community composition quickly converged with that of the conventional pen birds. This was validated through assessment of significantly different genera between hatch brood system and conventional pen birds, where numbers of significantly different taxa quickly decreased following the move. Some key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood birds. Conclusions: Overall, this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota, but its impact is resolved quickly once the birds are introduced into a conventional brood environment. Therefore, the benefits of pathogen reduction with hatch brood systems may outweigh negative microbiota impacts due to isolation.