Production and Transfer of In Vitro fertilized Hanwoo Embryos with Serum-free Media

As a simple and economical method for in vitro produced embryos, we have used BSA instead of serum for the production and embryo transfer of Hanwoo in vitro fertilized (IVF) embryos and obtained the following results: 1) When using serum (FBS; fetal bovine serum) or BSA-containing culture media as the initial culture media for immature oocytes, it is regarded as inappropriate to add only BSA to the culture solutions from maturation of the immature oocytes to development stage culture, but serum still needs be added though there is no significant difference in the concentration, with a change from 5% to 10%. 2) The results of culturing IVF embryos after development (4 cell stage) in the Medium199 solutions containing BSA instead of serum (FBS) showed that 0.3% BSA concentration is not optimal and 0.5% or higher BSA concentration has no significant difference among 0.5%, 0.7%, 1% and 2% (p > 0.05). 3) The post-freezing survival ratio after development in 5% FBS-Medium199 showed that 1% BSA concentration of the culture solution is the most suitable in the BSA concentrations of 0.3% (51%), 0.5% (67%), 0.7% (69%), 1% (77%) and 2% (75%). 4) The pregnancy rates of the transplanted fresh(not frozen) blastocyst had no significant concentration dependency (p > 0.5), and the average pregnancy rate was 63.8%. 14% of overweight calves were found among the calves given birth to by the transfer of IVF blastocysts cultured in the serum-added culture solution, but none was found in the experimental groups in which BSA was added instead of serum.