Funding for this research was provided by:
National Natural Science Foundation of China (31402038, 31772571, 31572369, 31572381)
Tan Sheep Breeding Project from Ningxia (NXTS201601)
China Agriculture Research System (CARS-40)
Text and Data Mining valid from 2018-05-25
Received: 26 August 2017
Accepted: 23 April 2018
First Online: 25 May 2018
Ethics approval and consent to participate
: All protocols involving the use of animals were approved by the College of Animal Science and Technology, Northwest A&F University (Approval ID: 2014ZX08008002).
: The authors declare that they have no competing interests.
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