title: In vitro development of OPU-derived bovine embryos cultured either individually or in groups with the silk protein sericin and the viability of frozen-thawed embryos after transfer.
abstract: The optimization of single-embryo culture conditions is very important, particularly in the in vitro production of bovine embryos using the ovum pick-up (OPU) procedure. The purpose of this study was to examine the development of embryos derived from oocytes obtained by OPU that were cultured either individually or in groups in medium supplemented with or without sericin and to investigate the viability of the frozen-thawed embryos after a direct transfer. When two-cell-stage embryos were cultured either individually or in groups for 7 days in CR1aa medium supplemented with or without 0.5% sericin, the rates of development to blastocysts and freezable blastocysts were significantly lower for the embryos cultured individually without sericin than for the embryos cultured in groups with or without sericin. Moreover, the rate of development to freezable blastocysts of the embryos cultured individually with sericin was significantly higher than that of the embryos cultured without sericin. When the frozen-thawed embryos were transferred directly to recipients, the rates of pregnancy, abortion, stillbirth and normal calving in the recipients were similar among the groups, irrespective of the culture conditions and sericin supplementation. Our findings indicate that supplementation with sericin during embryo culture improves the quality of the embryos cultured individually but not the viability of the frozen-thawed embryos after transfer to recipients.
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.|Kagoshima Prefectural Government Livestock Division, Kagoshima Prefecture, Kagoshima, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Isobe
authors.affiliation: Cattle Breeding Development Institute.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ikebata
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Lanh Thi Kim
authors.initials: LT
authors.lastname: Do
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Fuminori
authors.initials: F
authors.lastname: Tanihara
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Masayasu
authors.initials: M
authors.lastname: Taniguchi
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Takeshige
authors.initials: T
authors.lastname: Otoi
mesh_terms: D000818:Animals; D001755:Blastocyst; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects*; D003470:Culture Media / Q000494:pharmacology; D046149:Embryo Culture Techniques / Q000379:methods*; D004624:Embryo Transfer; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D005615:Freezing; D009865:Oocytes; D011247:Pregnancy; D011270:Pregnancy, Animal; D047030:Sericins / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D047030:Sericins
keywords: bovine embryos; in vitro development; ovum pick-up; pregnancy; silk protein