** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** GAS FLUX PHENOTYPES CAN BE UTILIZED TO IMPROVE EFFICIENCY AND SUSTAINABILITY OF BEEF PRODUCTION, PARTICULARLY WHEN COLLECTED ON GRAZING ANIMALS, GIVEN THIS SECTOR IS RESPONSIBLE FOR THE MAJORITY OF BOTH METHANE PRODUCTION AND MAINTENANCE COSTS IN THE BEEF INDUSTRY. FROM A GENETIC EVALUATION STANDPOINT, THE ABILITY TO HAVE SERIAL PHENOTYPES ON BREEDING ANIMALS, AS COULD OCCUR FOR COWS ON PASTURE, IS BENEFICIAL TO IMPROVING ACCURACY.WE WILL COLLECT GAS FLUX DATA ON GRAZING BEEF COWS, WHICH WILL PROVIDE INFORMATION ON METHANE PRODUCTION. THE REMAINING FLUXES (CARBON DIOXIDE AND OXYGEN) WILL PROVIDE THE RAW DATA NECESSARY TO CALCULATE METABOLIC RATE USING INDIRECT CALORIMETRY. THESE DATA WILL PROVIDE THE CORE NECESSARY TO DEVELOP A PROTOTYPE GENETIC EVALUATION FOR BOTH METHANE PRODUCTION AND METABOLIC RATE. TO UNDERSTAND THE CONSEQUENCES OF GENETIC SELECTION AND THE POTENTIAL FOR INDIRECT SELECTION TO IMPROVE THESE TRAITS, WE WILL QUANTIFY THE RELATIONSHIP BETWEEN THESE TRAITS AND OTHERS ALREADY COLLECTED AND EVALUATED IN THE INDUSTRY AS WELL AS DEVELOP A SELECTION INDEX, WHICH WILL PROVIDE ALL OF THE TOOLS NECESSARY TO MAKE IMPROVEMENTS IN THESE TRAITS IN A HOLISTIC FRAMEWORK WITHOUT SACRIFICING PRODUCTION EFFICIENCY OR GAINS IN OTHER ECONOMICALLY IMPORTANT TRAITS.STRONG SUPPORT FROM OUR BREED ASSOCIATION PARTNERS AND UTILIZATION OF METHODOLOGY AND GENETIC EVALUATION SYSTEMS ALREADY UTILIZED IN THEIR WEEKLY GENETIC EVALUATION WILL HELP TO SPEED TECHNOLOGY TRANSFER AND ADOPTION BY THE BEEF INDUSTRY, LEADING TO IMPROVED PRODUCTION EFFICIENCY AND SUSTAINABILITY.