** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** ASSISTED REPRODUCTION IS USED IN AGRICULTURE MAINLY TO PROPAGATE SUPERIOR GENETICS, WHILE IN HUMANS IT IS USED TO CIRCUMVENT PROBLEMS THAT CAUSE INFERTILITY (I.E., THE INABILITY OF A COUPLE TO CONCEIVE NATURALLY). ALTHOUGH THE USE OF ASSISTED REPRODUCTION HAS BEEN DRAMATICALLY INCREASING IN LIVESTOCK PRODUCTION, THERE IS STILL A LOT THAT WE DON'T UNDERSTAND ABOUT THE OVARY AND HOW IT WORKS, WHICH LIMITS THE SUCCESS OF THE TECHNIQUES CURRENTLY IN PLACE. THIS LACK OF KNOWLEDGE BECOMES A BARRIER TO EFFICIENTLY REPRODUCE LIVESTOCK ANIMALS FOR MORE SUSTAINABLE AGRICULTURE, AND IT IS ALSO CRITICAL AS WE TRY TO IMPROVE THE SUCCESS RATE OF HUMAN ASSISTED REPRODUCTION. THIS PROJECT FOCUSES ON HOW FOLLICLES ENCLOSING EGGS (OR FEMALE GAMETES) DEVELOP IN THE OVARY. FOR MANY YEARS, WE THOUGHT THAT MOST OF THE DEVELOPMENT OF OVARIAN EGGS HAPPENED INDEPENDENTLY OF HORMONES. MORE RECENT EVIDENCE SHOWS THAT THERE MIGHT BE SOME IMPORTANT ROLES OF HORMONES, BUT THE INFORMATION IS STILL VERY SCARCE. ONE OF THESE HORMONES IS FSH (WHICH STANDS FOR FOLLICLE STIMULATING HORMONE). FSH IS ONE OF THE MAIN HORMONES CONTROLLING REPRODUCTION. FOR THIS REASON, WE BELIEVE THAT FSH MIGHT HAVE BROADER EFFECTS ON THE OVARY THAN PREVIOUSLY KNOWN.USING A COMBINATION OF EXPERIMENTS IN COWS AND IN THE LABORATORY, WE WILLANSWER TWO QUESTIONS: 1) HOW EARLY IN THE DEVELOPMENT OF FOLLICLES IS FSH IMPORTANT; AND 2) HOW IS FSH ACTING IN THE FOLLICLES TO PROMOTE THEIR DEVELOPMENT. THIS INFORMATION WILL BE VERY IMPORTANT AS FSH IS ALREADY WIDELY USED IN PROGRAMS FOR ASSISTED REPRODUCTION. THE RESULTS OBTAINED HERE WILL INFORM VETERINARIANS AND HUMAN DOCTORS ABOUT CRITICAL, ALTHOUGH NOT YET FULLY KNOWN, WAYS IN WHICH FERTILITY IS REGULATED BY HORMONES. VERY IMPORTANTLY, THE RESULTS OF THIS PROJECT WILL ULTIMATELYIMPROVE THE TREATMENTS CURRENTLY AVAILABLE ANDTHE EFFICIENCY OF ASSISTED REPRODUCTION IN COWS, WHICH WILL IN TURN CONTRIBUTE TO MORE SUSTAINABLE LIVESTOCK PRODUCTION.