Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Animal and Veterinary Sciences

Committee Chair/Advisor

Dr. Ahmed Ali

Committee Member

Dr. Mireille Arguelles-Ramos

Committee Member

Dr. Jeryl Jones

Committee Member

Dr. William Bridges


Natural feed additives like oregano essential oil and synbiotic (prebiotic and probiotic) are options with great potential for increasing the health and welfare of laying hens. The first two studies explored the effects of dietary oregano essential oil (EOO) on performance, gastrointestinal traits (GIT), blood lipids, antioxidant capacity, and egg quality in laying hens from 0 to 40 weeks of age. The third study was conducted to examine dietary EOO on layers on the shelf life and fatty acid profile of eggs. The final study aimed to examine the effects of a dietary synbiotic on agonistic behavior, plasma and brain monoamines, stress parameters, and cecal microbiota counts via modulation of the MGB axis.

Author ORCID Identifier


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