This application from the University of California Davis (UCD) seeks base funding to continue operations of its Mouse Metabolic Phenotyping Center (MMPC) and to expands its gut microbiome research and development program. The mission of the MMPC-UCD is to advance medical and biological research by providing the research community with standardized, high quality metabolic and physiologic phenotyping services to validate and characterize mouse models of diabetes, diabetic complications, obesity and related metabolic disorders. Our Center is made up of an Administrative Core, an Animal Care Core, and 3 Phenotyping Cores: Endocrinology and Metabolism Core, Body Composition, Thermoregulation, and Food Intake Behavior Core, and Complications and Pathology Core. Over the last 5 years, our Center has provided over 27,500 services to more than 90 clients resulting in 53 publications and program income of over $700,000 that has been reinvested into the Center to expand and enhance service offerings to clients. In this renewal, our Center intends to extend and leverage past successes (e.g, bariatric surgery models, microbiome characterization, analysis of cognitive decline, dietary manipulation of body composition, etc) to continue to focus on clinically relevant and translatable mouse models. In response to input from the research community, we seek to provide phenotyping tests that will contribute to new, precision-guided paradigms of disease diagnosis and therapy. Our Center will offer services to measure physiologic parameters (e.g., cognition and brain metabolism), assess environmental influences (e.g., host- gut microbiome interactions), and determine the impact of mitigating factors (e.g., exercise) in client’s mice or in mouse models we make for clients. Our overall goal is to conduct resource- related research, develop and transform technologies into new services, and train the next generation of researchers using mutant mouse models for the study of diabetes, obesity, and related metabolic disorders. To achieve these goals, we will 1) provide users with validated and high quality fee-forservice tests, and to develop important new tests in endocrinology, metabolism, body composition, thermoregulation, cardiovascular disease, cognition, and exercise; 2) establish a Microbiome Research and Development Program incorporating projects that uncover the role of the microbiome in host metabolism, physiology and function, define the impact of the microbiome on disease prevention and pathology, and explore interactions between the microbiome and its metabolites; and 3) raise awareness among current and new users of the availability, accessibility, and usefulness of products and services unique to UCD, especially surgical models, phenotyping procedures, and de novo mouse models, and training in research tools to investigate mechanisms of metabolic disease. Achieving these goals will translate research in mice that advances the understanding of diabetes, obesity, and related metabolic disorders to improve diagnostics, therapeutics, and prevention strategies in humans.