一种复合益生菌对凡纳滨对虾抗副溶血弧菌感染能力的影响

本研究选择1株地衣芽孢杆菌(Bacillus licheniformis)BL-9、1株枯草芽孢杆菌(Bacillus subtilis)BS-12、1株金丽假交替单胞菌(Pseudoalteromonas flavipulchra)CDM8,以1∶1∶1将其组成复合益生菌,各益生菌水体添加浓度为107 CFU/ml,进行为期30 d的凡纳滨对虾(Litopenaeus vannamei)养殖实验。实验分为暂养期(7d)、益生菌处理期(15d)、副溶血弧菌(Vibrio parahaemolyticus)攻毒期(10 d)。结果显示,养殖水体中添加复合益生菌能显著增加水体和对虾肠道可培养细菌总数(P<0.05),攻毒实验结束时,实验组对虾累积存活率为(73.33±6.83)%,显著高于阳性对照组(25.33±15.43)%。对虾抗病基因热激蛋白70(Heat shock proteins 70,Hsp70)、β-1,3-葡聚糖结合蛋白-脂蛋白(Beta-1,3-glucan-binding protein-lipoprotein,βGBP-HDL)、脂多糖-β-1,3-葡聚糖结合蛋白(Lipopolysaccharide-β-1,3-glucan binding protein,LGBP)、抗菌肽Crustin在益生菌处理阶段均出现不同程度的上调,在攻毒阶段虽呈现各自不同的表达情况,但所有基因都经历了更大幅度上调。研究表明,水体中添加芽孢杆菌和假交替单胞菌组成的复合益生菌可提高凡纳滨对虾抗副溶血弧菌感染能力,对虾抗病力的提高可能与益生菌增加对虾肠道可培养细菌数量、抗病相关基因表达水平及过氧化氢酶(CAT)活性有关。

Effect of A Compound Probiotics on the Ability of Litopenaeus vannamei to Resist Vibrio parahaemolyticus Infection

In this culture experiments of Litopenaeus vannamei,we explore the effect of compound probiotics on the ability of L.vannamei to resist Vibrio parahaemolyticus infection at different experimental stages.One strain of Bacillus licheniformis(BL-9),one B.subtilis(BS-12),and one Pseudoalteromonas flavipulchra(CDM8)were selected to make up a compound of probiotics at the same concentration(107 CFU/ml).The effect of compound probiotics on the V.parahaemolyticus infection of L.vannamei was observed by adding the compound probiotics to the culture water of the L.vannamei.The experiment took place over 30 d,including a temporary period(7 d),a probiotics immersion period(15 d),and a V.parahaemolyticus infection period(10 d).The experiment results showed that the addition of compound probiotics in the culture water could significantly increase the total number of bacteria culture in the water and the intestinal tract of L.vannamei(P<0.05).The cumulative survival rate of shrimp in the experimental group was(73.33±6.83)%at the end of the infection periodwhich was significantly higher than that of the positive control group(25.33±15.43)%.The disease-resistant-related gene:heat shock protein 70(Hsp70),β-1,3-glucan binding protein-lipoprotein(βGBP-HDL),lipopolysaccharide-β-1,3-glucan binding protein(LGBP),crustin,and immune related enzymes catalase(CAT),was up-regulated by different degrees in the probiotics immersion phase.And all the genes up-regulated extensively during the V.parahaemolyticus infection stage,but expressed at different levels.The results suggested that the compound probiotics with BL-9,BS-12,and CDM8 in water could improve the ability of shrimp to resist V.parahaemolyticus infection.The increase of disease resistance of L.vannamei may be related to the colonization of probiotics in the intestinal tract,and the expression level of disease resistance related genes and catalase activity in L.vannamei.It is hoped that the results of this study can provide a reference for the application of compound probiotics in the cultivation of L.vannamei.