猪体内PEDV病原含量与血清中PEDV抗体水平之间的关系初探

The relationship between the PEDV pathogens and serum PEDV antibody level in pigs

旨在探究猪体内猪流行性腹泻病毒（PEDV）病原含量与血清中PEDV抗体水平之间的关系。以浙江某规模猪场为例,用横截面模型,分别采集不同日龄阶段商品猪口腔液与血清样本,应用荧光定量PCR和ELISA方法,分别检测两种样本中PEDV的抗原和抗体。统计分析其消长规律,并对两种样本中病原含量和血清中抗体含量进行相关性分析。结果显示：消化道途径的感染是引发PEDV各种保护性免疫活动的起始点,当猪群PEDV感染强度达到一定限度（〉103copies/μL）时才会引起猪体内抗体水平的变化;在不同感染强度下,猪口腔液和血清中病原含量与抗体水平之间呈现不同的相关性。初步揭示了猪体内病原含量与血清中PEDV抗体水平之间存在的相关性,为猪流行性腹泻的临床诊断和防控监测提供了新的思路。

In order to understand the relationship between the porcine epidemic diarrhea virus（PEDV） pathogens and the serum PEDV antibody level in pigs,both oral fluid and paired serum samples from different age groups of pigs,on a commercial farm,with known vaccination histories were collected and tested using real-time fluorescence quantitative PCR and ELISA. The results showed that alimentary canal infection was the initiation point of the protective immunity activities of PEDV. Only when the infection intensity reached a limitation point（103 copies/μL）,could immune antibodies against PEDV be stimulated; and different infection intensity degrees led to different correlations between the PEDV pathogens in the two kinds of samples and the serum antibody level. In conclusion,the correlation between the PEDV antibody level in serum and the PEDV pathogens in pigs was initially revealed in the present study,which provided a new perspective for clinical diagnosis,prevention and control of PED.