鱼用三联口服疫苗的制备方法及其对大菱鲆的免疫效果

Preparation of triple oral vaccine for fish and primary immune effect on turbot Scophthalmus maximus

为探究海水养殖中安全可靠、经济适用的疫苗接种方法,以药用淀粉、麦芽糊精,以及经0.5%甲醛灭活的溶藻弧菌Vibrio alginolyticus、副溶血弧菌V.parahemolyticus和迟缓爱德华氏菌Edwardsiella tarda为主要原料,采用挤出-滚圆法制备鱼用三联口服疫苗,并用其对大菱鲆Scophthalmus maximus免疫,分别在免疫0、7、14、21、28 d时测定溶藻弧菌、副溶血性弧菌和迟缓爱德华氏菌特异性抗体,以1×109cfu/m L活菌(3种菌液比例为1∶1∶1)进行攻毒试验并计算免疫保护率。结果表明,药用淀粉150 g、麦芽糊精50g、菌液60 m L、挤出速度200 r/min、滚圆时间60 s时,为比较成熟的三联口服疫苗制备工艺,用该疫苗免疫大菱鲆后,3种细菌的大菱鲆血清和后肠黏膜抗体效价均显著高于对照组,且免疫保护率达50%以上。

A triple oral vaccine for fish was prepared with medicinal starch, maltodextrin, and killed Vibrio parahe-molyticus ,Vibrio alginolyticus and Edwardsiella tarda by 0. 5 % formaldehyde,by extrusion and spheronization method,and turbot Scophthalmus maximus was immuned with the triple oral vaccine prepared. The indirect ELISA was used to measure the antibody titre of V. parahemolyticus, V. alginolyticus and E. tarda in serum and hindgut mucosa 0,7,14,21 and 28 days after vaccination. The relative percent survival （RPS） of the triple oral vaccine was calculated in the turbot challenged with live V. parahemolyticus, V. alginolyticus and E. tarda （ 1 ×10^9clu /mL, with ratio of V. parahemolyticusto, and V. alginolyticus to E. tarda = 1：1：1）. There was significantly higher antibody titer of the three bacteria in serum and hindgut mucosa,with RPS of more than 5 0 % for the three bacteria above, in the triple oral vaccine prepared by 150 g of medicinal starch,50 g maltdextrin,60 mL of bacterial liquid, extrusion at 200 r/min,and spheronization in 60 s than that in the control group.