1. Department of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang, China
2. Department of Life Sciences, Northeast Agricultural University, Harbin, Heilongjiang, China
3. Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, Harbin, Heilongjiang, China
4. Institute of Traditional Chinese Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang, China