** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** MODERN SWINE HAVE THE GENETIC POTENTIAL FOR ASTOUNDING GROWTH AND EFFICIENCY, BUT ACTUALLY ACHIEVING THIS POTENTIAL ON FARM REQUIRES MANAGEMENT STRATEGIES TO HELP ANIMALS DEAL WITH STRESSFUL EVENTS. WE HAVE PREVIOUSLY SHOWN THAT THYROID HORMONES, WHICH REGULATE METABOLIC ACTIVITY, FETAL DEVELOPMENT AND POSTNATAL GROWTH, ARE SUSCEPTIBLE TO DISRUPTION IN RESPONSE TO DISEASE. AS A RESULT, WE HYPOTHESIZE THAT OTHER STRESSORS DURING EARLY LIFE STAGES WILL SIMILARLY SUPPRESS THYROID HORMONE AND THEREBY COMPROMISE PRODUCTION EFFICIENCY. THE FIRST OBJECTIVE OF THIS PROJECT IS TO INVESTIGATE STRESS ASSOCIATED WITH WEANING OR TRANSPORT OF YOUNG PIGS, AND THE RESULTING IMPACT ON GROWTH PERFORMANCE AND GUT FUNCTION. THE SECOND OBJECTIVE OF THE PROJECT IS TO EXAMINE THE ROLE OF THYROID HORMONES IN FETAL AND PERINATAL DEVELOPMENT. THIS SECOND OBJECTIVE WILL FOCUS HEAVILY ON THE ASSOCIATION WITH FETAL GROWTH RESTRICTION WHICH REMAINS A PERSISTENT ISSUE WITHIN THE SWINE INDUSTRY. THE PRIMARY OUTCOMESOF THIS WORK WILL BE AN IMPROVED UNDERSTANDING OF PORCINE SPECIFIC THYROID BIOLOGY AS WELL AS A CAUSATIVE LINK BETWEEN THIS FUNDAMENTAL ENDOCRINE SYSTEM AND ANIMAL PERFORMANCE. INFORMATION IN THIS AREA WILL HAVE A CRITICAL IMPACT ON THE SWINE INDUSTRY, THROUGH DATA DRIVEN CHANGES TO ON-FARM MANAGEMENT STRATEGIES DESIGNED TO MAXIMIZING PRODUCTION EFFICIENCY.