Hu Zhiqiang, Li Yang, Zhang Bingzhou, Zhao Ying, Guan Ran, Zhou Yapeng, Du Jiafa, Zhang Zhimin, Li Xiaowen
College of Animal Science, Xichang University, No.1 Xuefu Road, Anning Town, Xichang, 615013, Sichuan Province, P. R. China.
Shandong Engineering Research Center of Pig and Poultry Health Breeding and Important Infectious Disease Purification, Shandong New Hope Liuhe Group Co., Ltd, No. 592-26 Jiushui East Road Laoshan District, 266100, Qingdao, Shandong, P. R. China.
Porcine Health Manag. 2024 Sep 3;10(1):32. doi: 10.1186/s40813-024-00382-w.
Porcine Epidemic Diarrhea (PED) is a highly contagious disease caused by Porcine Epidemic Diarrhea Virus (PEDV), resulting in a mortality rate of suckling piglets as high as 100%. Vaccination is the primary strategy for controlling PEDV infection, however, there is currently a lack of reliable methods for assessing the efficacy of vaccination. This study aimed to analyze serum and colostrum samples from 75 parturient sows with a specific vaccination strategy to measure levels of IgG, IgA, and neutralizing antibodies (nAbs) against PEDV, and to investigate the correlation between serum and colostrum antibody levels, as well as to identify potential biomarkers that can be used to evaluate immunization effects under field conditions.
The findings of correlation analysis between antibody levels of IgA, IgG, and nAbs in serum or colostrum samples revealed that IgG demonstrated the most robust correlation with nAbs exhibiting a correlation coefficient of 0.64 in serum samples. Conversely, IgA exhibited the highest correlation with nAbs, with a correlation coefficient of 0.47 in colostrum samples. Additionally, the correlation analysis of antibody levels between serum and colostrum samples indicated that serum IgA displayed the strongest correlation with colostrum IgA, with a coefficient of 0.63, indicating that serum IgA may serve as a viable alternative indicator for evaluating IgA levels in colostrum samples. To further evaluate the suitability of serum IgA as a substitute marker for colostrum IgA, levels of IgA antibodies in serum samples from sows were examined both pre- and post-parturition. The findings indicated that serum IgA levels were initially low prior to the initial immunization, experienced a notable rise 21 days after immunization, and maintained a significant elevation compared to pre-immunization levels from 21 days pre-parturition to 14 days postpartum, spanning a total of 35 days.
Serum anti-PEDV IgA antibody levels may serve as a valuable predictor for immunization effects, allowing for the assessment of colostrum IgA antibody levels up to 21 days in advance. This insight could enable veterinarians to timely adjust or optimize immunization strategies prior to parturition, thereby ensuring adequate passive immunity is conferred to piglets through colostral transfer postpartum.
猪流行性腹泻（PED）是由猪流行性腹泻病毒（PEDV）引起的一种高度传染性疾病，导致哺乳仔猪死亡率高达100%。疫苗接种是控制PEDV感染的主要策略，然而，目前缺乏评估疫苗接种效果的可靠方法。本研究旨在分析75头经特定疫苗接种策略的分娩母猪的血清和初乳样本，以测量针对PEDV的IgG、IgA和中和抗体（nAbs）水平，研究血清和初乳抗体水平之间的相关性，并确定可用于评估现场条件下免疫效果的潜在生物标志物。
血清或初乳样本中IgA、IgG和nAbs抗体水平的相关性分析结果显示，IgG与nAbs的相关性最强，血清样本中的相关系数为0.64。相反，IgA与nAbs的相关性最高，初乳样本中的相关系数为0.47。此外，血清和初乳样本之间抗体水平的相关性分析表明，血清IgA与初乳IgA的相关性最强，系数为0.63，表明血清IgA可作为评估初乳样本中IgA水平的可行替代指标。为了进一步评估血清IgA作为初乳IgA替代标志物的适用性，检测了母猪分娩前后血清样本中IgA抗体水平。结果表明，血清IgA水平在初次免疫前最初较低，免疫后21天显著升高，从产前21天到产后14天，共35天，与免疫前水平相比保持显著升高。
血清抗PEDV IgA抗体水平可能是免疫效果的有价值预测指标，可提前21天评估初乳IgA抗体水平。这一见解可使兽医在分娩前及时调整或优化免疫策略，从而确保产后通过初乳传递为仔猪提供足够的被动免疫力。
