Funding for this research was provided by:
Project of National Science and Technology Plan for the Rural Development in China (2015BAD03B06)
Key Technology Support Program of Sichuan Province (2016NYZ0044)
Received: 30 October 2019
Accepted: 21 May 2020
First Online: 5 June 2020
Ethics approval and consent to participate
: All animal handling procedures were approved by the Sichuan Agricultural University Animal Welfare Committee under DKY-B20141401.
: Not applicable.
: The authors declare that they have no competing interests.