Equine and Bovine Oocyte Maturation in a Novel Medium Without CO2 Gas Phase

Overnight holding aids in selection of developmentally competent equine oocytes

“…The successful method for overnight holding of equine oocytes in the absence of meiotic inhibitors was first reported in 2006 (Choi et al, 2006a). Since then, different holding periods, media, and temperatures were tested (Choi et al, 2007;Foss et al, 2013;Galli et al, 2014;Martino et al, 2014;Dini et al, 2016;Diaw et al, 2018;Martino et al, 2019;Campos-Chillon et al, 2019;Metcalf et al, 2020). Temperature sensitivity of equine oocytes differs depending upon the follicular stage.…”

"Assisted Reproductive Technologies in Horses: A Systematic Review"

“…Moreover, IVM protocols use growth factors like the epidermal growth factor (EGF), Fibroblast growth factors (FGF), insulin like growth factor (IGF) [18,25] or antioxidants. However, independently of the media supplementation, there are no significant differences in embryo development after IVF [7,11,12,14,15,18,19,[22][23][24][25][26][27][28]. Finally, the time of maturation in horses has not been established and varies widely among researchers.…”

“…Evidence suggests that holding media can improve nuclear maturation rates. There are different options for the holding media, which include commercial holding media, synthetic oviductal fluid, and a novel shipping/ maturation medium buffered with HEPES/NaHCO3 supplemented with antioxidants [7,11,19,24,26,28,29].…”