4Zhou Y J, Hao X F, Tian Z J, et al. Highly virulent porcine reproductive and respiratory syndrome virus emerged in China[J]. Transbound Emerg Dis, 2008,55 (3-4):52-64.
5Atbina E, Madec F, Cariolet R, et al. Immune response and persistence of the porcine reproductive and respiratory syndrome virus in infected pigs and farm units[J].Vet Rec, 1994( 134): 567- 573.
6Collins JE, Benfield DA, Christianson WT, et al. Isolation of swine inefrtiliy and respi- ratory syndrome virus (isolateATCCVR-2332) in North America and experimental reproduc- tion of the disease in gnotobiotic Pigs[J].J Vet Diagn Invest, 1992,4(2):117-126.
7Zhou lent YJ, Hao XF, Tian ZJ, et al. Highly viru porcine reproductive and respiratory syndrome virus emerged in China[J]. Trans- bound Emerg Dis, 2008,55(3-4):152-164.
8Nelson EA, Christopher-Hennings J, BenfieldDA of Serum immune responses to the proteins porcine reproductive and respiratory syn drome (PRRS) virus[J]. Vet Diagn Invest 1994,6:410-415.
9Meulenberg, J.J., Petersen den Besten, et al. Molecular characterization of Lelystad virus [J].VeterinaryMicrobiology, 1997,55:197 202.
10Ostrowski M, Galeota JA, Jar AM, et al. Iden tification of neutralizing and nonneutraliz ing epitopes in the porcine reproductive and respiratory syndrome virus GP5 ectodomain FT7[J]. Virol, 2002, 76:4241-4250.
