1. State Key Laboratory of Silkworm Genome Biology; Southwest University; Chongqing 400716 China
2. School of Mathematics and Finance; Chongqing University of Arts and Sciences; Chongqing 402160 China
3. Laboratory of Animal Biology; Chongqing Normal University; Chongqing 400047 China
4. College of Animal Science and Technology; Southwest University; Chongqing 400716 China