The antigenic and genetic variability of porcine reproductive and respirators syndrome virus ( prrsv ) isolates in china were studied by immunofluoresent monolayer assays ( 1fma ) and restriction fragment length polymorphism ( rflp ) of reverse transcription ( rt ) and polymerases chain reaction ( pcr ) amplified - prrsvorfs fragments among 8 chinese isolates 本研究通过对猪繁殖与呼吸综合征病毒( prrsv )国内分离毒株的gp3 、 gp5和n蛋白的抗原性比较及其orf5和orf7遗传变异性分析,系统研究了国内分离毒株的抗原特性和遗传学差异。