Acknowledgments
This study was supported by the Key Research Project of National Science and Technology (2016YFD0500108, 2016YFD0501003), the Chinese Natural Sciences Foundation (31672572), the Fundamental Research Funds for the Central Institutes Program (2019JB06), the Science and Technology Promoting Agriculture Innovation Project of Shanghai (2019 no. 3-3), and the Foundation of Shanghai Key Laboratory of Veterinary Biotechnology (klab201712).