TY - JOUR TI - Developmental competence of immature pig oocytes under the influence of EGF, IGF-I, follicular fluid and gonadotropins during IVM-IVF processes. AU - Illera, M J AU - Lorenzo, P L AU - Illera, J C AU - Petters, R M T2 - The International Journal of Developmental Biology AB - Epidermal growth factor (EGF) and insulin like growth factor-I (IGF-I) were evaluated for their effects on in vitro maturation and fertilization in presence or absence of gonadotropin and porcine follicular fluid. Four groups were made with the addition of growth factors: none (control), EGF, IGF-I or EGF+IGF-I. Each group underwent four predefined treatments with gonadotropin (FSH and LH), follicular fluid, a combination of both, or none (as control). Porcine cumulus-oocyte complexes (COCs) were matured in media containing the above-mentioned treatments for 42-44 h prior to fertilization with fresh sperm capacitated for 2.5 h. At the end of the fertilization period, the presumable embryos were fixed, stained and examined as whole-mounts to ascertain their nuclear status. The addition of EGF alone or in combination with IGF-I, significantly increased the proportion of monospermic oocytes forming 2 normal pronuclei. Also, supplementation with both growth factors together enhanced the percentages of pronucleus formation and total penetration. In addition, treatments with EGF+IGF-I significantly decreased (P PY - 1998 VL - 42 IS - 8 SP - 1169 EP - 1172 J2 - Int. J. Dev. Biol. LA - en SN - 0214-6282 SN - 1696-3547 UR - https://ijdb.ehu.eus/article/9879716 Y2 - 2024/04/29/10:36:08 ER -