BREEDING PROGRAMS HAVE IMPROVED THE GENETIC POTENTIAL OF SWINE RESULTING IN GREATER PERFORMANCE. HOWEVER, PERFORMANCE IMPROVEMENTS HAVE BEEN ACCOMPANIED BY A 55-70% INCREASE IN HEAT PRODUCTION FOR LACTATING SOWS AND HAVE REDUCED THEIR ABILITY TO COPE WITH HIGH TEMPERATURES. DECREASED HEAT TOLERANCE NEGATIVELY IMPACTS THE SOW'S ABILITY TO RAISE HER LITTER AND THE EFFECTS OF HEAT STRESS ON ANIMAL AGRICULTURE ARE EXPECTED TO WORSEN AND RESULT IN MORE ECONOMIC LOSSES, ESPECIALLY AS THE NUMBER AND SEVERITY OF HEAT WAVES INCREASE GLOBALLY. THEREFORE, THERE IS A CRITICAL NEED FOR RESEARCHERS TO DEVELOP NEW SELECTION TECHNIQUES AND MANAGEMENT PRACTICES TO ALLEVIATE THE NEGATIVE EFFECTS OF HEAT STRESS. THE OVERALL GOAL OF THIS PROPOSAL IS TO IDENTIFY NOVEL TRAITS AND VALIDATE GENOMIC SELECTION METHODS TO IMPROVE HEAT TOLERANCE WHILE IMPROVING LACTATING SOW PERFORMANCE. TO ACHIEVE THIS GOAL, WE WILL FIRST INVESTIGATE THE GENOMIC BACKGROUND OF THE HEAT STRESS RESPONSE AND THE PREDICTIVE PERFORMANCE OF GENOMIC SELECTION IN LACTATING SOWS USING GENOTYPES FROM >30,000 MATERNAL LINE PIGS AND PHENOTYPIC RECORDS FROM >45,000 SOWS AND >90,000 LITTERS. SECOND, WE WILL EVALUATE THE GENETIC ARCHITECTURE AND USEFULNESS OF BEHAVIORAL AND PHYSIOLOGICAL PHENOTYPES. FINALLY, WE WILL BIOLOGICALLY VALIDATE GENOMIC METHODS AND TRAITS TO IMPROVE HEAT TOLERANCE IN LACTATING SOWS BY COLLECTING IN-DEPTH PHENOTYPES IN SOWS WITH DIVERGENT GENOMIC BREEDING VALUES (LOW VS HIGH HEAT TOLERANCE) UNDER HEAT CHALLENGE. THIS PROPOSAL IS EXPECTED TO POSITIVELY IMPACT THE WELFARE AND PERFORMANCE OF LACTATING SOWS AND PIGLETS THEREBY INCREASING THE PROFITABILITY OF THE GLOBAL SWINE INDUSTRY AND IMPROVE FOOD SECURITY.

Purdue University, West Lafayette IN

Investigators