School of Life Science,Southwest University,Chongqing 400715,P.R.China;
College of Animal Science and Technology,Southwest University,Chongqing 400715,P..R.China;
Key Laboratory of Pig Genetics and Breeding,Ministry of Agriculture/Huazhong Agricultural University,Wuhan 430070,P.R.China;
Key Sericultural Laboratory,Ministry of Agriculture/Southwest University,Chongqing 400 715,P.R.China;
School of Life Science,Southwest University,Chongqing 400715,P.R.China;
Key Sericultural Laboratory,Ministry of Agriculture/Southwest University,Chongqing 400 715,P.R.China;
Key Laboratory of Pig Genetics and Breeding,Ministry of Agriculture/Huazhong Agricultural University,Wuhan 430070,P.R.China;
College of Animal Science and Technology,Southwest University,Chongqing 400715,P..R.China;