Key;
Laboratory;
of;
Animal;
Virology;
of;
Ministry;
of;
Agriculture,;
State;
Key;
Laboratory;
of;
Veterinary;
Etiologic;
Biology,;
Lanzhou;
Veterinary;
Research;
Institute,;
Chinese;
Academy;
of;
Agricultural;
Sciences,;
Lanzhou;
730046,;
China;
猪繁殖与呼吸综合征; 宁夏回族自治区; 遗传变异分析; 基因; 中国; 核苷酸序列; 分子流行病学; 遗传多样性;