Funding for this research was provided by:
the National Natural Science Foundation of China (31270186, 31572525)
Shanghai Jiao Tong University Agri-x Foundation (2015)
Received: 22 January 2017
Accepted: 16 April 2018
First Online: 27 April 2018
: Collection of pig fecal samples was performed after obtaining consent from the pig farm. All study protocols were approved by the Institutional animal care and use committee of the Shanghai Jiao Tong University. Experimental animals license Number: SYXK (shanghai) 2013–0052.
: The authors declare that they have no competing interests.
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