1. State Key Laboratory of Veterinary Etiological Biology; Lanzhou Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Lanzhou; Gansu Province; P. R. China
2. Department of Parasitology; National Institute of Infectious Diseases; Tokyo; Japan
3. Parasitology Division; Moredun Research Institute; Midlothian; Scotland; UK
4. Institute of Veterinary Medicine; Guangdong Academy of Agricultural Sciences; Guangzhou; Guangdong Province; P. R. China
5. College of Animal Science and Technology; Yunnan Agricultural University; Yunnan Province; P. R. China
6. School of Basic Medicine; Dali University; Dali; Yunnan Province; P. R. China
7. National Institute of Parasitic Diseases; Chinese Center for Disease Control and Prevention; Shanghai; P. R. China