title: Different culture media requirements of IVF and nuclear transfer bovine embryos.
abstract: Important differences exist between in vitro fertilized (IVF) and nuclear transfer (NT) bovine embryos. Studies have shown that although in vitro development is comparable, post-implantation survival is greatly reduced in NT embryos. In this study, we compare serum and bovine serum albumin (BSA) supplementation during oocyte maturation and embryo culture of IVF and NT embryos. In experiment 1, oocytes and embryos were randomly distributed into different treatment groups consisting of synthetic oviductal fluid (SOF) medium supplemented with either serum, fatty acid-free BSA (FAF) or fraction V BSA during maturation and/or culture to assess IVF embryo development. In experiment 2, oocytes were matured in SOF + serum or SOF + FAF and reconstructed embryos were cultured in SOF + FAF to assess NT embryo development. Among the IVF treatment groups, a greater number of blastocysts were observed in the steer serum (SER) group (IVM and IVC in SOF + serum) on day 6; however, no significant differences were seen in blastocyst development from day 8 onwards. Hatching frequencies on days 8 and 9 were significantly greater in groups with serum, with the exception of FAF (IVM and IVC in SOF + FAF) on day 9. For the NT treatment groups, the presence of serum during IVM resulted in a higher proportion of MII oocytes and increased blastocyst development and hatching rates were compared with supplementation of FAF. These results indicate that both serum and FAF provide comparable embryo development for IVF but not for NT bovine embryos.
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: G F
authors.initials: GF
authors.lastname: Mastromonaco
authors.forename: E
authors.initials: E
authors.lastname: Semple
authors.forename: C
authors.initials: C
authors.lastname: Robert
authors.forename: G J
authors.initials: GJ
authors.lastname: Rho
authors.forename: D H
authors.initials: DH
authors.lastname: Betts
authors.forename: W A
authors.initials: WA
authors.lastname: King
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000502:physiology; D001769:Blood; D001826:Body Fluids; D002417:Cattle / Q000196:embryology*; D003470:Culture Media; D047108:Embryonic Development / Q000502:physiology*; D005187:Fallopian Tubes; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary*; D053652:Nuclear Transfer Techniques; D012710:Serum Albumin, Bovine; D046509:Tissue Culture Techniques / Q000662:veterinary
chemical_list: D003470:Culture Media; D012710:Serum Albumin, Bovine