title: In vitro development of bovine embryos cultured with stem cell factor or insulin-like growth factor-I following IVF with semen of two bulls having different field fertility.
abstract: The usefulness of IVF as a potential tool to evaluate the field fertility of bulls is equivocal and growth factor addition to culture media research is needed to delineate components needed for providing defined environments for embryos. The overall aim was to evaluate the in vitro development of embryos derived using a serum supplemented and serum-free production systems and semen from two bulls of different field fertility. The study was conducted to determine the combinatorial effect of stem cell factor (SCF) and/or insulin-like growth factor-I (IGF-I) in culture on subsequent embryo development in cattle. Oocytes were aspirated separately from >or=3 to <3mm follicles to test different follicle size populations and were matured in TCM-199 supplemented with LH, FSH, estradiol and BSA (Fraction V). Matured oocytes were fertilized in BSA supplemented synthetic oviductal fluid (SOF)-IVF medium. Presumptive zygotes were cultured for 8d (in humidified 5% CO(2) at 38.5 degrees C) in BSA supplemented SOF-in vitro culture (IVC) medium. SOF-IVC medium was supplemented with fetal bovine serum (4%), IGF-I (100ng/mL), SCF (50ng/mL) or IGF-I (100ng/mL)+SCF (50ng/mL). The development competence of embryos did not differ between the bulls and among the culture environments. Nevertheless, there was an effect of follicle size on cleavage rate (P<0.05) and a greater cleavage rate resulted from oocytes aspirated from >or=3mm follicles (71.0+/-1.5%) compared to those collected from <3mm follicles (64.8+/-1.6%). The overall cleavage rate (%); blastocyst formation (%); and expanded/hatched blastocyst formation (%) were 68.2+/-1.5 and 67.7+/-1.7; 29.4+/-1.4 and 28.6+/-1.5; and 18.6+/-1.2 and 18.5+/-1.1, respectively, for the bull of above and below average field fertility. The results indicate that follicle size for oocyte aspiration is effective for determining IVC success and that IVF may not discriminate among bulls of different field fertility.
authors.affiliation: Department of Dairy Science, Virginia Polytechnic Institute and State University, 2070 Litton Reaves, Blacksburg, VA 24061-0315, USA.
authors.forename: A
authors.initials: A
authors.lastname: Dhali
authors.forename: V M
authors.initials: VM
authors.lastname: Anchamparuthy
authors.forename: S P
authors.initials: SP
authors.lastname: Butler
authors.forename: R E
authors.initials: RE
authors.lastname: Pearson
authors.forename: F C
authors.initials: FC
authors.lastname: Gwazdauskas
mesh_terms: D000818:Animals; D002417:Cattle; D002970:Cleavage Stage, Ovum / Q000187:drug effects / Q000502:physiology; D046149:Embryo Culture Techniques; D047108:Embryonic Development / Q000187:drug effects*; D004777:Environment; D005260:Female; D005298:Fertility / Q000502:physiology*; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary; D007248:Infertility, Male / Q000175:diagnosis / Q000662:veterinary; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008297:Male; D011247:Pregnancy; D012661:Semen / Q000502:physiology*; D019089:Stem Cell Factor / Q000494:pharmacology*
chemical_list: D019089:Stem Cell Factor; D007334:Insulin-Like Growth Factor I