Yan Lu1, Hongyan Dong1, Sujuan Chen1, Yiping Chen2, Daxin Peng1* and Xiufan Liu1
1College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, P. R. China.
2China Animal Health and Epidemiology Center, Qingdao, 266032, P. R. China.
