Funding for this research was provided by:
National Natural Science Foundation of China (31472203, 31172342)
National Key Research and Development Plan (2016YFD0901102)
the National Science and Technology Support Program of China (2013BAD12B05)
Received: 12 December 2019
Accepted: 29 December 2020
First Online: 18 January 2021
Ethics approval and consent to participate
: All of the animal protocols were performed in accordance with the ‘Guidelines for Experimental Animals’ of the Ministry of Science and Technology (Beijing, China), and the study was approved by the Research Ethics Committee of the Chinese Academy of Agricultural Sciences (permit number: 2015–014). No specific permits were required for these locations and activities. The owners gave their written consent for sample collection, and the locations where samples were collected are not privately owned or protected in any way.
: Not applicable.
: The authors declare that they have no competing interests.