Antibiotics as a Feed Additive Promote Growth of Chickens by Modulating the Gut Microbiome Xiangkai Li (
[email protected] ) Lanzhou University https://orcid.org/0000-0002-5704-9791 Ying Wu Lanzhou University Liang Peng Lanzhou University Rong Han Lanzhou University pengya Feng Lanzhou University Aman Khan Lanzhou University Pu Liu Lanzhou University Research Keywords: Antibiotic, Gut microbiota, Metabonomic, Lipid and amid acid metabolism, Immune response Posted Date: June 7th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-571302/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Page 1/31 Abstract Background: Antibiotics widely used as growth promoters in the agricultural industry, but their mechanisms have not been fully explored. Antibiotics has a connection effect on the gut microbiome which plays a vital role in host metabolism and immune response. Here, we investigated the association of antibiotic and gut microbiome in broiler chicken. Methods: Polymyxin (PMX) and amoxicillin (AMX) were selected as feed additives in broiler chicken, and gut bacterial composition assessed by quantitative real-time PCR and high-throughput sequencing of bacterial 16S rRNA. Metabolome and lipidomic of feces and serum samples were analyzed using liquid chromatograpy-tandem mass spectrometry (LC-MS). We further assessed changes in the microbiota and metabolism which underwent antibiotics treatment. Results: The administration of antibiotic increasing, the average weight of chickens by up to 4.9% and altered number and structure of the intestinal microora compared to the un-treated group. The bacterial component of gut microbiota in antibiotic groups was showed a lower prevalence of Firmicutes and Bacteroidetes phyla and higher prevalence of a high diversity (Proteobacteria).