仔猪口蹄疫母源抗体衰减规律研究

Attenuation patterns of the maternal antibody of foot-and-mouth disease in piglets

为了明确仔猪体内A型口蹄疫母源抗体衰减规律,为仔猪口蹄疫疫苗首免时间的确定提供理论依据,选取预产期相同、口蹄疫抗体水平(A型)有差异的5头母猪,每头母猪随机选取5头仔猪并分16个时间点采集外周血,利用液相阻断ELISA对仔猪体内A型口蹄疫抗体进行检测,评估其消减规律。结果显示:脐带血不传播母源抗体,仔猪获得母源抗体保护的唯一途径是吃母乳;仔猪采食初乳后体内A型口蹄疫母源抗体可在吃初乳后当天达到峰值,而后随时间增加而降低;当母猪分娩时抗体水平为1∶1024时,仔猪63日龄左右体内抗体水平降低至1∶45;当母猪分娩时抗体水平为1∶720时,仔猪56日龄左右体内抗体水平降低至1∶45;当母猪分娩时抗体水平为1∶360时,仔猪28日龄左右体内抗体水平降低至1∶45。仔猪体内A型口蹄疫抗体衰减时间和分娩时母猪抗体水平呈正相关性。本文研究结果为制定科学合理的仔猪口蹄疫疫苗免疫程序提供数据支撑。

In order to determine the attenuation patterns of the maternal antibody of foot-and-mouth disease(FMD)serotype A in piglet for the purpose of providing a theoretical basis for determining the first immunization time of foot-and-mouth disease vaccine for piglets,five sows with the same preterm but at different levels of foot-and-mouth antibody(type A)were selected.Five piglets were randomly chosen from each sow and peripheral blood samples were collected from the piglets at 16 time points,and the antibody of type A foot-and-mouth disease virus in the piglets was detected by liquid phase blocking ELISA to evaluate the attenuation patterns of the antibody.The results showed that the umbilical cord blood of the piglets did not transmit their maternal antibody,and feeding on the breast milk was the only way to obtain maternal antibody protection for the piglets.The maternal antibody of type A foot-and-mouth disease in the piglets after taking their mothers’milk reached the peak value on the first day,and then decreased with the passing time.Furthermore,when the antibody level of the sows was 1:1024,the antibody level of the piglets reduced to 1:45 at 63 days of age.When the antibody level of the sows was 1:720,the antibody level of the piglets decreased to 1:45 at 56 days of age.When the antibody level of the sow was 1:360,the antibody level of the piglets fell to 1:45 at 28 days of age.The piglets relied on the colostrums from their mothers to get antibody,and there was a positive correlation between the time of maternal antibody attenuation in piglets and the level of the antibody in the sows during childbirth.The present results provided data support for the development of scientific and reasonable immune procedure for FMD vaccine in piglets.