** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** OUR LONG-TERM GOAL IS TO DEVELOP XENOGENESIS (METHOD OF REPRODUCTION IN WHICH SUCCESSIVE GENERATIONS DIFFER FROM EACH OTHER) RESULTING IN XENOGENS (AN ORGANISM COMPRISED OF ELEMENTS TYPICALLY FOREIGN TO ITS SPECIES) TO INCREASE EFFICIENCY OF REPRODUCTION FOR CATFISH HYBRIDIZATION. OUR OVERALL OBJECTIVE IS TO IMPROVE XENOGENESIS EFFICIENCY IN CATFISH BY INCREASING COLONIZATION OF STEM CELLS, DEVELOPING EARLY DETECTION TECHNIQUES TO IDENTIFY XENOGENIC INDIVIDUALS, AND EVALUATION OF LONG-TERM REPRODUCTIVE PERFORMANCE OF XENOGENIC CATFISH.CURRENTLY, CHANNEL CATFISH FEMALE X BLUE CATFISH MALE HYBRID CATFISH EMBRYOS ARE PRODUCED BY HORMONE-INDUCED OVULATION AND HAND STRIPPING TO OBTAIN THE EGGS FOLLOWED BY THE SACRIFICE OF BLUE CATFISH MALES TO OBTAIN SPERM. ARTIFICIAL FERTILIZATION IS THEN USED TO PRODUCE THE EMBRYOS. THIS IS LABOR INTENSIVE AND 6 YEARS ARE REQUIRED FOR THE BLUE CATFISH MALES TO REACH SEXUAL MATURITY FOR A SINGEL USE. XENOGENESIS WOULD BE ADVANTAGEOUS AND PROTOCOLS HAVE BEEN DEVELOPED THAT SHOULD ALLOW COMMERCIALIZATION WITH THE OPTIMIZATION THAT WILL RESULT FROM THE CURRENT PROJECT.FOR THIS OPTIMIZATION, WE PLAN TO IMPROVE PURIFICATION AND PROPAGATION OF DONOR STEM CELLS AND COMPARE THE EFFECTIVENESS OF INJECTION OF FRESH MIXED DONOR CELLS WITH INJECTION OF PURE CULTURED CELLS FOR PRODUCING XENOGENICINDIVIDUALS, TO COMPARE SURGICAL BIOPSY WITH DNA ANALYSIS AND ELISA FOR DONOR PROTEINS FOUND IN THE CIRCULATORY SYSTEM FOR EARLY DETECTION OF XENOGENIC INDIVIDUALS AND TO EVALUATE THE MULTIPLE YEAR REPRODUCTIVE PERFORMANCE AND LONGEVITY OF XENOGENIC CATFISH AND THE CAPACITY OF MALES TO MATE MULTIPLE FEMALES IN THE SAME YEAR.BECAUSE OF THE PERFORMANCE OF HYBRID CATFISH, A POSITIVE OUTCOME WILL LEAD TO GREATER OUTPUT OF HYBRID CATFISH EMBRYOS. THIS WILL LEAD TO GREATER PRODUCTION, EFFICIENCY, AND SUSTAINABILITY IN THE CATFISH INDUSTRY, AND ENHANCE THE QUALITY OF RURAL LIFE. OTHER POWERFUL GENETIC AND CONSERVATION APPLICATIONS ARE POSSIBLE.