Funding for this research was provided by:
National Natural Science Foundation of China (31672548, 31330079)
Natural Science Foundation of Henan Province (162300410129)
National Key Research and Development Program of China (2017YFD0500400, 2017YFD0501305, 2016YFD0500707)
China Agriculture Research System (CARS-35)
Text and Data Mining valid from 2019-03-28
Received: 11 November 2018
Accepted: 18 March 2019
First Online: 28 March 2019
: This study was performed in accordance with the Chinese Laboratory Animal Administration Act of 1988. Before the experiments, the research protocol was reviewed and approved by the Research Ethics Committee of Henan Agricultural University. Permission was obtained from all managers of the study pig farms before the fecal samples were collected.
: Not applicable.
: The authors declare that they have no competing interests.
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