THROUGH AN ENVIRONMENTALLY CONTROLLED STUDY AND A FIELD INVESTIGATION, THIS PROJECT WILL DEVELOP AND EVALUATE AN ENGINEERING PRODUCT TO MITIGATE HEAT STRESS IN HEAVY BROILERS AND AMMONIA EMISSION FOR IMPROVED BROILER PRODUCTION PERFORMANCE AND WELFARE. THE SPECIFIC OBJECTIVES ARE TO:(1) OBTAIN HEAT AND MOISTURE PRODUCTION VALUES FOR HEAVY BROILERS UNDER DIFFERENT TEMPERATURE (T), RELATIVE HUMIDITY (RH) AND AIR VELOCITY (AV) SET POINTS;(2) ASSESS IMPACT OF THE HIGH AV FOR DIFFERENT T AND RH SET POINTS UNDER SUMMER CONDITIONS ON THE PERFORMANCE AND WELFARE OF HEAVY BROILERS;(3) DEVELOP A RETRACTABLE BAFFLE SYSTEM TO RE-DISTRIBUTE VENTILATION AIR, THEREBY INCREASING AIRFLOW AT THE BIRD HEIGHT IN THE GROW-OUT CYCLE TO MITIGATE HEAT STRESS IN HEAVY BROILERS;(4) EVALUATE THE EFFECTS OF THE BAFFLE SYSTEM AND THE RESULTANT IMPROVED AIRFLOW ON THE EXISTING HOUSING VENTILATION SYSTEM, AMMONIA AND PARTICULATE MATTER CONCENTRATIONS AS WELL AS BROILER PERFORMANCE AND WELFARE.THE PROJECT WILL BE CONDUCTED BY A MULTIDISCIPLINARY TEAM WITH EXPERTISE IN BROILER PRODUCTION AND WELFARE, HOUSING ENVIRONMENTAL CONTROL, AIR QUALITY, AND WASTE MANAGEMENT. THIS PROJECT WILL PRODUCE (1) NEW KNOWLEDGE ON HEAT AND MOISTURE PRODUCTION OF HEAVY BROILERS UNDER DIFFERENT T/RH/AV COMBINATIONS; (2) A COST-EFFECTIVE ENGINEERING SOLUTION FOR MITIGATING HEAT STRESS AND AIR QUALITY TO IMPROVE HEAVY BROILER PERFORMANCE AND WELFARE. KNOWLEDGE OBTAINED WILL HELP GUIDE THE POULTRY INDUSTRY TO IMPROVE ENGINEERING DESIGN OF HOUSING VENTILATION SYSTEM FOR WELFARE FRIENDLY AND SUSTAINABLE PRODUCTION SYSTEMS.