1. College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China
2. International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China
3. Henan Engineering Laboratory of Animal Biological Products, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China
4. Longhu Modern Immunology Laboratory, Zhengzhou, Henan, China