Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Veterinary Microbiology and Preventive Medicine


Microbiolo gy

First Advisor

Torey Looft


The intestinal microbiota has a profound impact on the health and productivity of poultry species, making the acquisition, composition, and functional contributions of individual community members of vital importance for producers. Determining the source(s) of the initial microbial inoculum from which newly hatched chicks establish their intestinal microbiota and assessing the functionality of individual intestinal microbes can provide producers with potential interventions to achieve the improvements in animal health and performance. Here, we evaluate the impacts of different inocula sources, namely the eggshell- and the environmental-associated microbial communities, on the establishment and successional processes along the intestinal tract of newly hatched chicks. It was found that both the eggshell and environmental microbiota contribute to microbial succession in the poultry intestinal tract. Interestingly, the eggshell seems to play an appreciable role in the development of the small intestine microbiota, specifically the jejunum and ileum, where the microbial community structure of birds exposed exclusively to the eggshell microbiota significantly resembled the structure of conventionally raised birds. Additionally, a novel species of Turicibacter was isolated from chicken eggshells and the swine ileum. Novel Turicibacter isolates were genomically characterized and their physiological responses to chicken bile and individual bile acids were compared. Turicibacter strains were capable of deconjugating bile acids, potentially impacting host nutrient absorption. Future research should focus on the application of well-described microbial consortia to drive beneficial successional processes in the intestinal tract of poultry and the further description of novel bacteria that have the potential to impact host health and productivity.


Copyright Owner

Joel Jacob Maki



File Format


File Size

219 pages