1Department of Animal Science, College of Agriculture, Shahid Bahonar University of Kerman, Kerman, Iran.
2Department of Animal Science, College of Agriculture and Natural Resources, University of Kurdistan, Sanandaj, Iran.
3Department of Animal and Marine Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
The nutritional requirements of mammalian embryos changes throughout pre-implantation period, coincident with changes in the secretion of the female reproductive tract. Therefore, it has been suggested that sequential culture media may support nutritional requirements for optimal growth of the mammalian embryos. In this study, we investigated the effect of two different concentrations (10 or 100 ng/ml) of epidermal growth factor (EGF) in sequential media on bovine embryo cleavage rate and blastocyst formation. Oocytes were aspirated from 2- to 6- mm follicles and transferred to maturation media. After 24 h incubation in a CO2 incubator, matured oocytes were inseminated. Presumptive fertilized oocytes after 22 h incubation were cultured in human sequential G1/G2 media containing 0, 10 or 100 ng/ml EGF. The experiment was performed in three replicates and the data were recorded as percentage of cleaved embryo and blastocysts formed. EGF did not significantly affect the cleavage rate but more blastocysts were formed in media containing 100 ng/ml EGF (p