猪塞尼卡谷病毒病灭活疫苗免疫持续期测定

Immune duration of inactivated vaccine against swine Seneca V alley virus disease

旨在研究猪塞尼卡谷病毒病灭活疫苗的免疫持续期。将两批实验室制品颈部肌肉注射2~3月龄健康猪,2.0 mL/头,免疫后21 d加强免疫1次,首次免疫后7、14、21、28、35、50、80、110、140、170、200 d分别采血,测定塞尼卡谷病毒(SVV)中和抗体效价,并于170 d和200 d分别随机抽取5头猪进行攻毒,以攻毒保护率均高于80%的最长免疫时间确定为疫苗的免疫持续期。免疫时间从第一次免疫后开始计算。结果显示,两批实验室制品免疫后7 d血清SVV中和抗体效价平均达1∶10以上;免疫后21 d中和抗体平均达1∶82.5以上;免疫后50 d血清抗体达到顶峰,中和抗体平均达1∶938.4以上。之后抗体呈下降趋势。免疫后170 d中和抗体平均达1∶192.1以上,免疫后200 d中和抗体平均达1∶73.8以上。免疫后170和200 d攻毒,保护率均达100%。试验结果说明,猪塞尼卡谷病毒灭活疫苗免疫期至少可维持到200 d,具有重要研发前景。

This study was to test the immune duration of inactivated vaccine against Seneca Valley virus(SVV)disease.Two batches of laboratory products were injected into 2-3 months old healthy pigs,at 2.0 mL/pig.The immunization was intensified 21 days later.Then,blood samples were collected on days 7,14,21,28,35,50,80,110,140,170 and 200,respectively,after immunization,to determine the titer of the SVV neutralizing antibody.On days 170 and 200,five pigs were randomly selected for virus challenge.And the longest immunization time was determined as the immune duration of the vaccine with the challenge protection rates all higher than 80%.Immunization time was calculated from the beginning after the first immunization.The results showed that,on the 7th day after immunization with the two batches of laboratory products,the average titer of the serum SVV neutralizing antibody was more than 1:10.On the 21st day after immunization,the average titre of the neutralizing antibody was 1:82.5 or above.The serum antibody peaked on the 50th day after immunization,and the average titre reached above 1:938.4.Then,the antibody showed a downward trend.Its average titre on day 170 after immunization was over 1:192.1,and that on day 200 was over 1:73.8.When the virus was challenged on day 170 and day 200 after immunization,its protection rates reached 100%.To sum up,the immune period of inactivated vaccine against Seneca Valley virus could persist for at least 6 months,and the immune process was safe and without adverse reactions.