1 College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Livestock Biology, Northwest A&F University, Yangling, Shaanxi 712100, China.
2 College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Livestock Biology, Northwest A&F University, Yangling, Shaanxi 712100, China; Department of Animal Science, Fars Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education & Extension Organization (AREEO), Fars, Iran.
3 College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Livestock Biology, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: chuanyingpan@126.com.
4 College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Livestock Biology, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: ran.li1986@hotmail.com.