Nestle, EmilyContinued improvements in embryo culture media composition allow for the growth of high quality blastocysts, which can be used to derive embryonic stem cells (ESCs). ESCs are capable of becoming any cell type in the body making them a valuable research tool for therapeutic and regenerative research, while furthering our understanding of embryonic development and cell differentiation. The domestic cat is an important model species for both human medicine and wild felids. Cat embryo culture produces blastocysts at a rate far below that of the mouse and initial attempts at deriving cat ESCs have resulted in embryonic stem-like cells, which cannot be maintained indefinitely. In this study we assessed and compared the quality of cat blastocysts produced <italic>in vitro</italic> using two commercial human blastocyst growth media, and the maintenance of pluripotency markers OCT-4 and NANOG in inner cell mass explants from <italic>in vitro</italic> produced blastocysts over 14 days.ThesisAnimal sciencesBiologyblastocystcatembryomediumprotein