Funding for this research was provided by:
The authors are grateful to the fund by Gansu Agricultural Bio-tech R&D program (GNSW-2009-10)
Gansu Youth research program (1208RJAY079)
Received: 20 August 2017
Accepted: 18 July 2018
First Online: 17 August 2018
Ethics approval and consent to participate
: The piglets were purchased from the farmers, and they provide consent for the pigs to be used in the study. All animal experiments were performed according to protocol by the Animal Ethics Procedures and Guidelines of the People’s Republic of China. The study was approved by the Animal Ethics Committee of Lanzhou Veterinary Research Institute of Chinese Academy of Agricultural Sciences (Permit No. LVRIAEC2016–008).
: Not applicable.
: The authors declare that they have no competing interests.
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