母猪血清PEDV S1IgG抗体水平与中和抗体水平的相关性

Correlation between serum PEDV S1IgG antibody levels and neutralizing antibody levels in sows

旨在探究母猪血清中的猪流行腹泻病毒(porcine epidemic diarrhea virus,PEDV)S1IgG抗体水平与中和抗体效价的相关性。收集免疫背景清晰的PEDV感染场、未感染场和免疫背景不清晰的感染场各5个场的血清和返饲后备猪血清,共计716份,分别测定PEDV S1IgG抗体和中和抗体,分析两者之间的相关性。结果发现,母猪血清的PEDV S1IgG和中和抗体呈极显著正相关,相关系数(r)为0.892(P<0.0001)。而已往研究表明母猪血清PEDV中和抗体水平的高低与仔猪母源抗体抗PEDV感染的能力相关。因此可以通过检测母猪血清中的PEDV S1IgG抗体来评估仔猪的母源抗体抗PEDV的能力。在10个PEDV感染场中,母猪在免疫后血清中的PEDV中和抗体普遍偏高,S1IgG抗体也高,其S/P值高于3.5的占66.9%(347/519),并且其中没有PED发生的4个猪场抗体水平最高,而在5个PEDV未感染场中,免疫母猪的中和抗体普遍偏低,其S1IgG抗体也低,其S/P值高于3.5的仅有8.1%(13/161)。结果表明,PEDV感染场的猪群通过免疫后,大部分母猪可以给仔猪提供较好的免疫保护,而PEDV未感染场的猪群如需要达到较高的免疫保护水平则需要进一步强化免疫。本研究为使用PEDV S1IgG抗体水平评估猪群中PEDV抗体保护效果提供了临床检测依据。

The aim of this study was to investigate the correlation between porcine epidemic diarrhea virus(PEDV)S1IgG antibody levels and neutralizing antibody potency in sow sera.Sera from 5PEDV-infected farms with a clear immune background,5non-infected farms and 5infected farms with an unclear immune background,and sera from return-fed reserve pigs,totaling 716copies,were collected and measured,and the correlation between PEDV S1IgG antibodies and neutralizing antibodies was analyzed.The results showed that the PEDV S1IgG and neutralizing antibodies of sow sera showed highly significant positive correlation,the correlation coefficient was 0.892(P<0.0001).Previous studies have shown that the level of PEDV neutralizing antibodies in sow serum correlates with the ability of piglets'maternal antibodies to resist PEDV infection.Therefore,the ability of maternal antibodies against PEDV in piglets can be evaluated by detecting PEDV S1IgG antibodies in the serum of sows.In 10PEDV-infected farms,the neutralizing antibodies to PEDV in the sera of sows after immunization were generally high,and the S1IgG antibodies were also high,and their S/P values were higher than 3.5in 66.9%of the farms(347/519),and the highest antibody levels were found in the four farms in which PED did not occur,whereas the neutralizing antibodies in the immunized sows in the five PEDV-uninfected farms were generally low,and their S1 IgG antibodies were also low,and only 8.1%(13/161)having S/P values higher than 3.5.The results suggest that most sows in PEDV-infected farms can provide good immunoprotection to piglets after immunization,while pigs in PEDV-uninfected farms need further immunization if they need to achieve a higher level of immunoprotection.The present study provides a substantial clinical basis for the use of PEDV S1IgG antibody levels to assess the effectiveness of PEDV antibody protection in swine herds.