Short Title: Amino Acid Turnover and Bovine Oocyte Quality Summary Sentence: Bovine oocytes with differing developmental competence in vitro displayed different rates of amino acid turnover. Keywords: Amino acid profiling, oocyte quality, developmental potential, bovine

Amino acid profiling has been used to distinguish between human embryos of differing developmental competence. We sought to determine whether amino acid profiling could be used to distinguish between Metaphase II (MII) bovine oocytes with different developmental capabilities in vitro. Amino acid turnover was assayed during the final 6 hours of in vitro maturation prior to oocytes undergoing individual fertilization in vitro. Following insemination, zygotes were immobilized in groups of sixteen on the base of a Petri dish using Cell-Tak tissue adhesive to enable the developmental progress of each to be tracked to the blastocyst stage. Spent droplets of IVM medium were analyzed by HPLC, which revealed glutamine, arginine and asparagine to be depleted in the greatest quantities. Incompetent MII