1. National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080–8555, Japan
2. Veterinary Research Institute, P.O. Box 28, Peradeniya, Sri Lanka
3. Institute of Biotechnology, Hue University, 7 Hanoi Street, Hue 47000, Vietnam
4. Hue University of Agriculture and Forestry, 102 Phung Hung Street, Hue 47000, Vietnam