THE PRODUCTION OF POND-RAISED CATFISH IS THE LARGEST SECTOR OF THE U.S. AQUACULTURE INDUSTRY AND A VITAL COMPONENT OF SEVERAL SOUTHEASTERN STATES. MORTALITY RESULTING FROM DIRECT EXPOSURE TO WATERBORNE STAGES AND LOST PRODUCTION ASSOCIATED WITH PARASITE INDUCED ANOREXIA RESULT IN SIGNIFICANT MONETARY LOSSES. MANAGEMENT IS DEPENDENT ON HOST EXCLUSION AND ERADICATION TO PREVENT TRANSMISSION OF THESE PARASITES IN CATFISH PRODUCTION SYSTEMS AND MITIGATION EFFORTS ARE ESTIMATED TO COST PRODUCERS MILLIONS OF DOLLARS ANNUALLY. CATFISH PRODUCERS AND INDUSTRY LEADERS EMPHASIZE A CRITICAL NEED FOR RESEARCH FOCUSED ON INCREASING OUR UNDERSTANDING OF TREMATODE BIOLOGY AND DEVELOPMENT OF MORE EFFICIENT/COST EFFECTIVE MANAGEMENT STRATEGIES. HOWEVER, THE COMPLEX LIFE CYCLES FOR MANY TREMATODES AFFECTING CATFISH ARE LARGELY UNKNOWN. WE PROPOSE AN INTEGRATED STUDY TO IDENTIFY ALL POTENTIAL VECTORS, THROUGH SURVEYS OF TREMATODE LIFE STAGES IN AVIAN, MOLLUSCAN, AND FISH HOSTS USING A POLYPHASIC APPROACHEMPLOYING CLASSICAL PARASITOLOGY, MOLECULAR BIOLOGY AND NEXT-GENERATION SEQUENCING. MOST IMPORTANTLY, WE WILL ESTABLISH PROPHYLACTIC TREATMENTS USING A TWO-PRONGED APPROACH TARGETING LARVAL AND JUVENILE SNAILS, AS WELL AS LARVAL TREMATODE STAGES (EGGS AND MIRACIDIA). PROPHYLACTIC ERADICATION OF JUVENILE SNAILS AND LARVAL TREMATODE STAGES WILL DISRUPT TREMATODE LIFE CYCLES, AND IN TURN, PREVENT INFECTIONS IN FISH BEFORE SIGNIFICANT LOSSES CAN OCCUR AND TREATMENT OPTIONS BECOME LIMITED. THE OBJECTIVES PROPOSED HEREIN ALIGN WITH THE USDA SPECIAL RESEARCH GRANTS PROGRAM FOR AQUACULTURE, SPECIFICALLY THE FUNDING OF APPLIED RESEARCH FOCUSED ON CRITICAL DISEASE ISSUES IMPACTING COMMERCIAL AQUACULTURE SPECIES. THE ATTACHED LETTERS FROM INDUSTRY STAKEHOLDERS ATTEST TO THE URGENCY AND IMPORTANCE OF THE RESEARCH OUTLINED IN THIS PROPOSAL TO ENSURE THE SUSTAINABILITY AND PROFITABILITY OF U.S. CATFISH AQUACULTURE.