母源抗体对猪口蹄疫疫苗免疫应答的影响

Effects of maternal antibodies on host′s responses to immunized foot and mouth disease vaccine

用液相阻断ELISA(Liquid phase blocking ELISA,LPB-ELISA)和正向间接血凝(Indirect hemagglutination test,IHAT)2种血清学试验方法对规模化饲养猪群仔猪的口蹄疫母源抗体、母源抗体的传递途径、消长规律、母/仔代特异抗体相关性及母源抗体对口蹄疫疫苗免疫的影响进行了研究和分析。结果表明,2种血清学方法均没有从未吸吮初乳的新生仔猪中检出特异抗体;在吸吮初乳后的仔猪血清中可检出特异性抗体,并于10日龄左右抗体效价升至峰值,而后随着日龄的增加,特异性抗体的效价呈明显的线性下降,母源抗体半衰期约为10～20d,至45～60日龄母源抗体效价降至不完全保护带(lgX<1.8)或更低;仔猪母源抗体水平与母体特异抗体水平呈正相关。通过对不同日龄仔猪接种口蹄疫疫苗后抗体水平检测发现,仔猪体内较高水平的母源抗体对疫苗免疫应答具有明显或一定的负面影响。

Using liquid phase blocking ELISA and indirect hemagglutination test,maternal antibodies against foot and mouth disease,their passing routes and fluctuating rules were detected in infant pigs raised at scale in order to analyze the corelationship between the maternal special antibodies and the specific ones in infants,and the effects of the maternal antibodies on immunization with a foot and mouth disease vaccine.The results indicated that specific antibodies were detected in newly-born pigs eating colostrums but not detected in the pigs without eating colostrums,and that the specific antibodies reached a top at 10 days after birth,followed by obvious decrease with aging and reaching an incomplete protection level（lgX1.8）or even lower.The half life of the specific antibodies was proved to be 10-20 d.The specific antibodies in infants and their mothers were as positive correlativity.Antibody level in different-age infants with immunization of foot and mouth disease vaccine revealed that high level of the maternal antibodies has obviously negative effects on host＇s responses to immunized vaccine.Theses provide informative data in establishment of reasonable immunization protocols and scientific use.