THIS PROJECT FOCUSES ON IMPROVING SWINE PRODUCTION DURING HOTTER SUMMER MONTHS BY IDENTIFYING TRAITS AND DEVELOPING GENOMIC SELECTION STRATEGIES TO REDUCE THE NEGATIVE IMPACTS OF IN UTERO HEAT STRESS ON HEALTH, PRODUCTION, AND WELFARE OUTCOMES OF OFFSPRING. WE WILL ANALYZE GENETIC DATA FROM OVER 100,000 PIG LITTERS IN COLLABORATION WITH U.S. SWINE BREEDING COMPANIES TO IDENTIFY PIGS AT HIGH OR LOW RISK OF PASSING ON IUHS-RELATED TRAITS. USING THIS INFORMATION, WE WILL BREED PIGS WITH IMPROVED HEAT TOLERANCE AND TEST THEIR OFFSPRING'S HEALTH, GROWTH, AND STRESS RESPONSES TO BIOLOGICALLY CHARACTERIZE THE EFFECTS OF THE GENOMIC SELECTION MODEL. ADDITIONALLY, WE INVESTIGATE WHETHER IN UTERO HEAT STRESS-RELATED CHANGES IN THE GENETICS OF OFFSPRING BE PASSED TO FUTURE GENERATIONS AND WHETHER SELECTING HEAT-TOLERANT SOWS CAN PREVENT THESE CHANGES. THROUGH THIS WORK, WE AIM TO ENHANCE HEAT TOLERANCE, REDUCE IN UTERO HEAT STRESS IMPACTS, AND IMPROVE PRODUCTIVITY AND WELFARE ACROSS GENERATIONS.