EARLY IN LIFE, PIGS UNDERGO INTESTINAL DISTRESS FROM WEANING, CAUSED BY SEPARATION FROM THEIR MOTHERS, DIETARY CHANGES, AND INTRODUCTION TO A NEW ENVIRONMENT. WEANING EVENTS LEAD TO SHIFTS IN THE INTESTINAL MICROBIOTA, INCREASED LEAKINESS OF THE INTESTINAL TRACT, INCREASED LEVELS OF STRESS HORMONES, AND INTRODUCTION OF NEW DIETARY AND ENVIRONENTALMOLECULES THAT CAN STIMULATE THE IMMUNE SYSTEM; HOWEVER, NEGATIVE WEANING IMPACTS ARE REDUCED BY WEANING ANIMALS AT A LATER AGE. ALL THE AFOREMENTIONED FACTORS ARE KNOWN TO INFLUENCE IMMUNE CELLS RESIDING IN THE LINING OF THE INTESTINAL TRACT, WHICH ARE SOME OF THEEARLIEST IMMUNE CELLS RECRUITED TO THE INTESTINE AND PLAY AN IMPORTANT ROLE IN SHAPING THE IMMUNE ENVIRONMENT EARLY IN LIFEAND SUBSEQUENT OVERALL ANIMAL HEALTH. THOUGH IMMUNE CELLS WITHIN THE INTESTINAL LINING HAVE BEEN IDENTIFIED IN PIGS, THE ROLE OF THESE CELLS IN DIFFERENT HEALTH OUTCOMES RELATED TO WEANING AGE HAS NOT BEEN WELL ESTABLISHED.TO INVESTIGATE, PIGS WILL BE WEANED AT 21 OR 28 DAYS OF AGE, AND ABUNDANCE, TYPES OF CELLS, AND FUNCTION OF IMMUNE CELLS LOCATED WITHIN THE INTESTINAL LINING WILL BE EVALUATED IN THE WEEKS FOLLOWING WEANING. MARKERS OF INTESTINAL LEAKINESS AND DIFFERENCES OF BACTERIA IN THE INTESTINE WILL ALSO BE ASSESSED FOR CORRELATION WITH IMMUNE CELL DYNAMICS.COLLECTIVELY, THE ULTIMATE GOAL IS TO IDENTIFY NON-ANTIBIOTIC INTERVENTION STRATEGIES AFFECTING THE INTESTINAL IMMUNE SYSTEM IN EARLY LIFE TO IMPROVE INTESTINAL AND OVERALL HEALTH. TOWARDS THIS GOAL, THIS RESEARCH WILL DEMONSTRATE HOWWEANING AGE INFLUENCES IMMUNE CELLS IN THE INTESTINAL LINING AND THEIR ROLE IN ESTABLISHING DIFFERENT HEALTH OUTCOMESIMPORTANT FOR IDENTIFYING MECHANISMS BY WHICH EARLY LIFE INTERVENTION STRATEGIES CAN POSITIVELY IMPACT INTESTINAL IMMUNE STATUS AND OVERALL ANIMAL HEALTH.