Scott T.  Willarda, Song-yi  Jung, Susan D.  Bowers, 
    Simulated Microgravity Influences Bovine Oocyte <I>in vitro</I> Fertilization and Preimplantation Embryo Development,
    Journal of Animal and Veterinary Advances,
    Volume 8,Issue 9,
    2009,
    Pages 1807-1814,
    ISSN 1680-5593,
    javaa.2009.1807.1814,
    (https://makhillpublications.co/view-article.php?doi=javaa.2009.1807.1814)
    Abstract: The aim of this study was to investigate, whether <I>in vitro </I>fertilization and preimplantation embryos exposed to a simulated microgravity environment <I>in vitro</I> would improve, or be deleterious to their fertilization and embryonic development. A Rotating Cell Culture System&#153; (RCCS) bioreactor with a High Aspect Ratio Vessel (HARV) was used to simulate a microgravity environment. <I>In vitro</I> Fertilization (IVF) and Culture (IVC) were conducted in standard microdrop culture method conditions (Control) and simulated microgravity conditions; HARV rotated at 34 rpm (high speed) and at 3.7 rpm (Low speed) on a horizontal axis. Embryonic development rates were determined during IVF (experiment 1), during IVC at presumptive zygote stage (experiment 2) and IVC at 2-8 cell stages of embryo development (experiment 3). For IVF studies (experiment 1), 77.3% of bovine oocytes were fertilized in the Control group; however, bovine oocytes and sperm fertilization did not occur in high and low speed groups. Moreover, none of the presumptive zygotes (experiment 2) and 2-8 cell stage embryos (experiment 3) cultured in high and low speed groups were able to develop to the further stages. These results indicate that simulated microgravity environments have a negative impact on bovine <I>In vitro</I> fertilization and preimplantation embryo development.
    Keywords: Bovine embryo;in vitro fertilization;in vitro culture;simulated microgravity