猪细小病毒7型PCR检测方法的建立及应用

Establishment and application of PCR assay for the detection of porcine parvovirus 7

为评估猪细小病毒7型（porcine parvovirus 7,PPV7）在猪群中的流行,根据Gen Bank中PPV7全基因组序列设计1对扩增PPV7 NS1基因的特异性引物,并建立PCR方法。对该引物的退火温度进行优化,且分析其特异性和敏感性。结果显示,在52-72℃退火温度范围内该对引物均能特异性扩增出目的基因片段,最低检测限为3.6×10 2copies/L。对不同来源的282份组织样品和来自湖南省4个不同猪场的226份血清样品进行检测,结果,组织样品中PPV7检出率为55.0%（155/282）,血清中PPV7检出率为10.2%（23/226）。其中,屠宰猪组织样品中PPV7检出率最高（71.4%）,而PPV7感染对猪的健康是否存在影响还不能确定。本研究结果为PPV7流行病学的研究奠定了一定的基础。

Porcine parvovirus 7（PPV7） is a newly discovered parvovirus.To investigate the prevalence of PPV7 in pig herds,a pair primer was designed to specially amplify partial NS1 gene form the samples based on the PPV7 complete genome sequence in Gen Bank.The optimized annealing temperature of PCR reaction was preformed and its specificity and sensitivity were analyzed.The results showed that the target gene fragment could be specifically amplified from 52 to 72 ℃ in the annealing temperature range and the detection limit of the assay was 3.6×102 copies/L.282 tissue samples,which were collected from different sources and 226 serum samples collected from four farms in Hunan Province,were evaluated by PCR and PPV7 was detected in 55.0%（155/282）of the tissue samples and 10.2%（23/226）of the serum samples.Notably,PPV7 had the highest prevalence rates in tissue samples of slaughter pigs（71.4%）,but whether PPV7 infection is associated with the health status of pigs remains unclear.This above-mentioned results provided foundation for the epidemiological study of PPV7.