1. Laboratory of Veterinary Embryology and Biotechnology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Korea.
2. Institute of Stem Cell & Regenerative Medicine, Chungbuk National University, Cheongju 28644, Korea.
3. Department of Biotechnology, School of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea.