Funding for this research was provided by:
National Natural Science Foundation of China (31572557, 31772784)
Special Fund for Agro-scientific Research in the Public Interest (201303040 and 201403051)
Priority Academic Program Development of Jiangsu Higher Education Institutions
Fundamental research funds for the central universities (Y0201700441, KYYJ201803)
Text and Data Mining valid from 2019-05-07
Received: 13 June 2018
Accepted: 29 April 2019
First Online: 7 May 2019
: This study was approved by the Animal Ethics Committee of Nanjing Agricultural University (approval no. 2012GGC15003).
: Not applicable.
: The authors declare that they have no competing interests.
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