1. 1Key Laboratory of New Animal Drug Project, Gansu Province; Key Laboratory of Veterinary Pharmaceutics Discovery, Ministry of Agriculture; Lanzhou Institute of Animal Science and Veterinary Pharmaceutics Science, Chinese Academy of Agricultural Sciences, Lanzhou 730050, Gansu Province, P. R.China
2. 2College of Chemical Engineering, Shijiazhuang University, Shijiazhuang 050035, Hebei Province, P. R.China