Effect of Endophyte-Infected Tall Fescue Toxins on Growth Performance and the Microbial Community in the Rumen and Feces in Pregnant Ewes

Fifty pregnant Katahdin ewes grazed pastures with high (HE) and moderate (MI) levels of Neotyphodium coenophialum-infected tall fescue between February 1 and May 24 to determine the impacts of tall fescue toxins on body weight (BW), body condition scores, FAMACHA scores, fecal egg counts (FEC), and serum Cu, Zn, prolactin, and non-esterified fatty acids (NEFA). Within those 50 ewes, 15 were selected randomly for fecal and rumen sampling to assess the impacts of HE and MI on the microbiome community. Total bacterial DNA was extracted from rumen and fecal samples, and alpha and beta diversities were used to relate microbiome data diversity with forage treatments and physical and physiological measurements. Most of the ewe physical and physiological measurements were not affected by endophyte levels. However, body weight changes (d 51 to d 115) and NEFA changes (d 51 to d 115) were greater in MI than HE. The HE group had greater observed ruminal OTUs, Shannon, Chao, and beta diversities at d 115 than MI. Members of Bacteroidetes_Prevotella ruminal bacteria OTUs were correlated with BW changes, prolactin concentrations, NEFA changes, and FEC. Also on d 115, there was an increased abundance from Firmicutes in HE vs. MI (60% vs. 53 %, respectively). The HE group had greater observed fecal OTUs, Shannon, and Chao, on d 51 than MI, but beta diversities did not differ between HE and MI during the study. Members of Actinobacteria_Coriobacteriaceae_unclassified fecal OTUs were correlated with BW changes, prolactin concentrations, NEFA changes, and FEC. At the end of the study, there was decreased abundance from Bacteroidetes in MI and HE (52.9 % and 49.3 %, respectively). Shifting of rumen or fecal bacteria populations that occurred could be a direct effect of the ergot alkaloids or indirect effects of toxins on intake or digestibility that subsequently impacted the bacterial populations. It is also possible that the bacteria that detoxify ergot alkaloids are minor species that have yet to be classified. Further research in the rumen or fecal microbial and their changes in responses to grazing endophyte-infected fescue needs to be considered to identify bacteria responsible for the detoxification. Acknowledgments First of all, I would like to thank God “Allah” for giving me the strength and health to take on the mission of acquiring solid and great scientific career. My journey to seek a PhD degree would not have even begun without the encouragement and suggestion I received from my major advisor, Prof. Kenneth Coffey. He has been a wonderful leader as well as an example in my life and has facilitated very much personal growth in me. My most profound appreciation goes to him for giving me the opportunity to pursue my dream and above all my parent's dream. I could not have accomplished this dissertation and my degree without his effort, and tremendous patient. Next, as a member of his lab, I would like to thank Dr. Jiangchao Zhao, for supporting, guiding and providing an opportunity for learning and training in microbiome field. I could not get the microbiome work done without his endless encouragement and suggestions. I also would like to thank Dr. Joan Burke, for providing me a chance to join USDA-ARS Boonville Folks. It would not have been possible to achieve my degree without her helping and supporting. I would acknowledge Dr. Dirk Philipp and Dr. Mary Savin for honoring me to serve as a member in my dissertation advisory committee. A special appreciation goes to my lab mate, Jianmin Chai, for helping, supports, and the great time we had together. I also would like to thank USDA-ARS group, Erin Wood, Connie Cox, Chad Lee, and Samuel Tabler. Also, I would thank my office mates Valens Niyigene, Mohan Acharya, Jose Diaz Gomez, and Jase Ball, whom I think without them around me every day in our office or outside having a gathering sometimes, it would not be possible to go through this scientific journey. My thanks also pass to secretaries and staffs at the department, Doug Galloway, Linda, Robert Story, Jamie Newberry, Linda Jones, Khalisa Kits, Jeannie, Dianna, Connie, Dr. Palika, Tes, and TC thank very much for all help and supports. In addition, I would experss my thanks to my wife’s brothers (Eng. Enad) and (Eng. Adel) for supporting me and helping me over the years. Also, I would like to thank my neighbours (Badar Alharbi) and Grayson’s mother (Tamara) for helping me to pick my kids from school during my busy time. Dedication This dissertation is dedicated to my loving Father (Abdullah) and Mother (Shamrokhah), for all the hard work for raising me in the right way. Their encouragement and devotion are making me what I am today. As she parts of my life, I would like to dedicate my work to my wife, (Abeer) in recognition of all the steady supports that she has always provided over the years. Moreover, I would not forget the support of my beautiful kids, Abdullah, Deema, and Azzam, I love all of you and I promise you to make your life better. Also, I would like to express my gratitude to my brothers, Thaier, Rathi, Turkey, Mohammed, Ahmad, Omar, and Faisal, also to my all sisters and our family, who has strongly encouraged and supported me during my Ph.D study. Table of contents Page number