2017-2020年广西部分猪场送检血清猪伪狂犬病抗体检测

Detection of Antibodies against PRV in Serum Samples Delivered by Some Swine Farms in Guangxi from 2017 to 2020

为了解广西猪场伪狂犬病毒(PRV)感染和免疫状况,2017年1月—2020年12月,对部分猪场随机采样送检的血清样品,应用ELISA方法开展PRV血清抗体检测,并对检测结果进行不同年份、不同季节、不同地区、不同生长阶段猪群的统计分析。结果显示:从时间分布上看,2018年PRV gE抗体场阳性率(57.71%)和个体阳性率(24.75%)均最高,此后呈逐年下降趋势,其中个体阳性率下降明显(P<0.05),2020年下降至6.14%;各年间的PRV gB抗体场合格率差异不显著(P>0.05),均在90%以上,而2019年的个体阳性率(88.71%)最低,与其他年份差异显著(P<0.05)。冬季PRV gE和gB抗体个体阳性率最低,分别为14.96%和89.35%,与其他季节差异明显(P<0.05);冬季gE抗体场阳性率(42.97%)最低,与春季、秋季差异不显著(P>0.05),但显著低于夏季(P<0.05),而gB抗体场合格率一年四季差异不显著(P>0.05),均在95%以上。从空间分布上看,广西14个地市猪场均存在不同程度的PRV野毒感染,其中玉林市最严重,场阳性率和个体阳性率分别为69.51%和35.86%,而钦州市最轻,分别为16.67%和4.07%;PRV gB抗体个体合格率普遍较高,均在84%以上。从不同生长阶段猪群上看,后备母猪、育肥猪PRV gE和gB抗体个体阳性率均显著低于其他生长阶段猪群(P<0.05),其中gE抗体个体阳性率在13%以下,而gB抗体个体阳性率不足80%。结果表明,近年广西规模猪场PRV野毒感染率较高,而疫苗免疫并不能完全阻止野毒株感染。建议通过PRV净化和提高规模猪场生物安全水平等措施来控制其流行。本研究为制定合理的猪伪狂犬病防控与净化策略提供了依据。

In order to investigate the status of infection and immune of porcine pseudorabies virus(PRV)in swine farms in Guangxi,serum samples randomly collected from some farms during January 2017 to December 2020 were detected for antibodies against PRV by ELISA,the results were summarized and analyzed according to diff erent years,seasons,regions and pig populations at diff erent ages.The results showed that the positive rates of antibodies against PRV gE at farm level(57.71%)and individual level(24.75%)were highest in 2018,then trended to decrease year by year,especially the individual one that even decreased to 6.14%in 2020(P<0.05);the qualifi cation rates of antibodies against PRV gB at farm level were above 90%and the diff erence was not signifi cant in all these years(P>0.05),but the positive rate at the individual level was lowest in 2019(88.71%),and signifi cantly diff erent from those in other years(P<0.05).The individual positive rates of antibodies against PRV gE and gB were 14.96%and 89.35%respectively,lowest in winter,and obviously diff erent from those in other seasons(P<0.05);the positive rates of antibodies against gE at farm level were lowest in winter(42.97%),and not signifi cantly diff erent from those in spring and fall(P>0.05),but signifi cantly lower than those in summer(P<0.05),while those of antibodies against gB were above 95%and the diff erence throughout the year was not signifi cant(P>0.05).For spatial distribution,PRV wild virus was present in all the farms to diff erent extent,most serious in Yulin City where the positive rates at farm and individual level were 69.51%and 35.86%,respectively,and lightest in Qinzhou City where were 16.67%and 4.07%,respectively;The individual qualifi cation rates of antibodies against gB were all above 84%and generally higher.For pig populations at diff erent ages,the individual positive rates of antibodies against gE and gB in reserved sows and fi nishing pigs were signifi cantly lower than those at other stages(P<0.05),specifi cally,the individual positive rate of antibodies against gE was less than 13%,while that of antibodies against gB was less than 80%.In conclusion,the infection rate of PRV wild virus was relatively high in large-scale farms in Guangxi,which could not be fully controlled by vaccination,so PRV purifi cation and improvement of bio-safety level in the farms were recommended.A basis was thereby provided for developing reasonable measures for PRV prevention,control and purifi cation.