1. College of Veterinary Medicine, Hebei Agricultural University, Baoding, Hebei 071000, China
2. Veterinary Biological Technology Innovation Center of Hebei Province, Baoding, Hebei, 071000, China
3. Hebei Shengxue Dacheng Pharmaceutical (Tangshan) Co., Ltd., 064000, China
4. Pharmaceutical Materials Science and Engineering Laboratory, Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA