title: Normal calves produced after transfer of embryos cultured in a chemically defined medium supplemented with epidermal growth factor and insulin-like growth factor I following ovum pick up and in vitro fertilization in Japanese black cows.
abstract: The objective of this study was to examine whether high concentrations of epidermal growth factor (EGF) and/or insulin-like growth factor I (IGF-I) would have a beneficial effect on bovine embryo development in vitro and to obtain normal calves by using an ovum pick up method and embryo culture in a chemically defined medium. When compared with controls, EGF (100 or 200 ng/ml) or IGF-I (50 or 100 ng/ml) significantly increased the rate of embryos that developed into blastocysts during an 8-day culture after the in vitro fertilization of oocytes obtained from ovaries from a slaughterhouse. IGF-I induced a dose-dependent increase in cell number in both the inner cell mass and the trophectoderm, whereas EGF stimulated proliferation only in the inner cell mass. A combination of EGF (100 ng/ml) and IGF-I (50 ng/ml) produced an additive effect, and embryos developed into blastocysts at a comparatively high rate (27.9%) compared with controls (12.0%). A similar rate of development was achieved using a combination of EGF and IGF-I in the culture of embryos following ovum pick up by ultrasound-guided transvaginal follicular aspiration and in vitro fertilization, and 5 blastocysts that developed after the culture were transferred into uteri; two embryos implanted, and normal calves were born. These results suggest that the combined use of EGF and IGF-I makes bovine embryo culture in a chemically defined medium a practical and useful procedure for producing blastocysts, and its application to embryo culture following ovum pick up and in vitro fertilization could be useful for producing normal calves.
authors.affiliation: Livestock Industry Technology Station, Kanagawa Agricultural Technology Center, Kanagawa 243-0417, Japan. sakagami.semi@pref.kanagawa.jp
authors.forename: Nobutada
authors.initials: N
authors.lastname: Sakagami
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Umeki
authors.forename: Osamu
authors.initials: O
authors.lastname: Nishino
authors.forename: Hiroko
authors.initials: H
authors.lastname: Uchiyama
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ichikawa
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takeshita
authors.forename: Etsushi
authors.initials: E
authors.lastname: Kaneko
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Akiyama
authors.forename: Shuji
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Tamada
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000187:drug effects; D002417:Cattle; D049109:Cell Proliferation / Q000187:drug effects; D003470:Culture Media / Q000494:pharmacology; D004359:Drug Therapy, Combination; D004624:Embryo Transfer / Q000379:methods* / Q000662:veterinary; D047108:Embryonic Development / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D054315:Oocyte Retrieval / Q000662:veterinary*; D009865:Oocytes / Q000187:drug effects; D046509:Tissue Culture Techniques / Q000662:veterinary*
chemical_list: D003470:Culture Media; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I