1. College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering and Technology Northwest A&F University Yangling China
2. Institute of Stem Cell and Regenerative Biology, College of Animal Science and Veterinary Medicine Huazhong Agricultural University Wuhan China
3. Key Laboratory of Animal Cellular and Genetic Engineering of Heilongjiang Province, College of Life Science North‐East Agricultural University Harbin China