Ethical compliance
The SPF chickens and chicken embryos used in this study were purchased
from Nanjing Biology Medical Factory, Qian Yuan-hao Biological Co, Ltd..
Procedures involving the care and use of animals were approved by the
Jiangsu Administrative Committee for Laboratory Animals (permission
number SYXK 2016-0020) and performed in accordance with the Jiangsu
Laboratory Animal Welfare and Ethics guidelines of the Jiangsu
Administrative Committee of Laboratory Animals.