Project Grant 20237704541007

** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** HEAT STRESS IS A MAJOR HEALTH AND PRODUCTIVITY CHALLENGE FACING THE LAYING HEN INDUSTRY. VARIOUS PHYSIOLOGICAL CHANGES OCCUR IN LAYING HENS IN RESPONSE TO HEAT STRESS. ONE OF THE MAJOR CONSEQUENCES IS OXIDATIVE STRESS, WHICH INCLUDES THE PRODUCTION OF EXCESS FREE RADICALS. THEREFORE, INCREASING THE ANTIOXIDANT INTAKE OF BIRDS HAS BEEN PROPOSED AS A MITIGATION STRATEGY FOR HEAT STRESS BY ADDRESSING OXIDATIVE STRESS. ANTIOXIDANT ACTIVITIES INCLUDE NEUTRALIZING FREE RADICALS, REDUCING THEIR ABILITY TO CAUSE CELLULAR DAMAGE. A NUMBER OF ANTIOXIDANT COMPOUNDS HAVE DEMONSTRATED BENEFICIAL EFFECTS; HOWEVER, TO DATE, THERE HAVE BEEN NO INVESTIGATIONS OF XANTHOPHYLL CAROTENOIDS. XANTHOPHYLLS ARE POTENT ANTIOXIDANTS AND ANTI-INFLAMMATORY AGENTS THAT HAVE HIGH PHYSIOLOGICAL ACTIVITY WITHIN LAYING HENS AS THEY ARE INVOLVED IN YOLK PIGMENTATION AND BIOACCUMULATE THROUGHOUT THEIR BODIES, PROVIDING THEIR DISTINCTIVE YELLOW FAT, BEAKS, SHANKS, AND FEET.THE PROPOSED RESEARCH PROJECT SEEKS TO INVESTIGATE THE ROLE XANTHOPHYLL CAROTENOIDS PLAY IN THE PHYSIOLOGICAL RESPONSE OF LAYING HENS DURING A HEAT STRESS EVENT. FURTHERMORE, THIS PROPOSAL SEEKS TO DETERMINE IF INCREASING CAROTENOID INTAKE CAN BE USED AS A STRATEGY TO HELP MITIGATE THE NEGATIVE HEALTH AND PRODUCTION EFFECTS OF HEAT STRESS. FINALLY, THIS PROJECT SEEKS TO EVALUATE HIGH CAROTENOID ORANGE CORN AS AN ALTERNATIVE FEED INGREDIENT TO DELIVER THESE POTENTIAL BENEFITS TO LAYING HENS IN A COMMERCIAL ALTERNATIVE HOUSING PRODUCTION SYSTEM EXPERIENCING EXTREME SEASONAL WEATHER CONDITIONS. ORANGE CORN IS A NOVEL TYPE OF CORN THAT HAS SIGNIFICANTLY HIGHER XANTHOPHYLL CAROTENOID LEVELS WHEN COMPARED TO YELLOW CORN. FURTHERMORE, THE CAROTENOIDS IN ORANGE CORN APPEAR TO BE MORE BIOAVAILABLE THAN COMMERCIALLY AVAILABLE CAROTENOID SUPPLEMENTS, MAKING IT AN ATTRACTIVE ALTERNATIVE FOR DELIVERING HIGHER LEVELS OF CAROTENOIDS INTO THE DIETS OF LAYING HENS.THIS PROPOSAL SEEKS TO TEST THE HYPOTHESIS THAT ORANGE CORN WILL BE ABLE TO DELIVER MORE CAROTENOIDS INTO THE BLOOD AND TISSUES OF LAYING HENS AND THUS INCREASE THEIR TOTAL ANTIOXIDANT CAPACITY. IT IS HYPOTHESIZED THAT THIS, IN TURN, WILL REDUCE OXIDATIVE STRESS, HELPING TO STABILIZE LAYING HEN HEALTH AND PERFORMANCE DURING A HEAT STRESS EVENT.THIS PROJECT WILL MAKE A MEANINGFUL CONTRIBUTION TO POULTRY SCIENCE AND THE LAYING HEN INDUSTRY FOR A NUMBER OF REASONS: (1) THERE IS A NEED FOR MORE INVESTIGATION INTO THE EFFECTS OF HEAT STRESS ON LAYING HENS, AS THE MAJORITY OF WORK HAS BEEN CONDUCTED ON BROILERS; (2) THERE IS A NEED FOR INVESTIGATION INTO HOW HEAT STRESS EFFECTS LAYING HENS ACROSS THEIR LIFETIME; (3) THERE HAVE BEEN NO PREVIOUS INVESTIGATIONS INTO THE ROLE OF XANTHOPHYLL CAROTENOIDS IN THE LAYING HEN'S RESPONSE TO HEAT STRESS; AND (4) IF SUCCESSFUL, THIS PROJECT WOULD OFFER THE LAYING HEN INDUSTRY A PRACTICAL NUTRITIONAL APPROACH FOR ADDRESSING HEAT STRESS THAT ALSO ENHANCES YOLK PIGMENTATION AND THE NUTRITIONAL QUALITY OF THE TABLE EGG, ONE OF AMERICA',S MOST IMPORTANT SOURCES OF PROTEIN.