title: Influence of epidermal growth factor on in vitro maturation of equine oocytes.
abstract: The effect of epidermal growth factor (EGF) on the in vitro maturation rate of equine oocytes was examined. Oocytes were collected from an abattoir (Expt 1) or using ultrasound-guided follicular puncture in vivo (Expt 2). All oocytes with a compact or expanded cumulus at recovery were cultured for 30 h in: medium 1 (TCM199 + fetal calf serum (FCS) + crude equine gonadotrophin (CEG) + oestradiol + antibiotics); medium 2 (TCM199 + EGF); medium 3 (medium 1 without FCS + EGF); or medium 4 (medium 1 without CEG + EGF). In Expt 1, 84% (37/44) and 87% (40/46) cumulus expansion (P > 0.05), and 39% (22/57) and 9% (5/57) (P < 0.01) nuclear maturation, were observed in medium 1 and 2, respectively. In Expt 2, cumulus expansion was observed after culture in medium 1, 3 and 4 (30/30, 31/31 and 29/29, respectively). The nuclear maturation rate was significantly lower in medium 3 (6%, 2/36) than in medium 1 (43%, 16/37) (P < 0.01) and was higher in medium 4 (64%, 25/39) than in medium 1, although the effect was not significant (P = 0.07). In conclusion, 50 ng EGF ml(-1) alone was an effective substitute for crude equine gonadotrophin and the presence of EGF improves the nuclear maturation rate of equine oocytes.
authors.affiliation: INRA-Haras Nationaux, Equipe de Reproduction Equine, 37380 Nouzilly, France.
authors.forename: G
authors.initials: G
authors.lastname: Goudet
authors.forename: F
authors.initials: F
authors.lastname: Belin
authors.forename: W
authors.initials: W
authors.lastname: Młodawska
authors.forename: J
authors.initials: J
authors.lastname: Bézard
mesh_terms: D000818:Animals; D002467:Cell Nucleus; D003470:Culture Media; D003593:Cytoplasm; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D006736:Horses / Q000502:physiology*; D008540:Meiosis / Q000187:drug effects; D009865:Oocytes / Q000502:physiology*
chemical_list: D003470:Culture Media; D006064:Gonadotropins, Equine; D004815:Epidermal Growth Factor