Funding for this research was provided by:
the National Natural Science Foundation of China (31272603, 31101836)
Received: 9 February 2018
Accepted: 22 May 2018
First Online: 7 June 2018
: This study has gained ethical approval for this study. Our study was conducted according to the Ethics Committee of Animal Experiments at the Institute of Husbandry and Pharmaceutical Sciences of CAAS in Lanzhou, China. And we gained consent from the owners of the animals for them to be used in the study.
: The authors declare that they have no competing interests.
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