添加外源益生菌对大菱鲆育苗生物饵料菌群结构的影响

为评价在大菱鲆育苗生产中添加外源益生菌对生物饵料轮虫和卤虫微生物菌群结构的影响,运用基于illumina HiSeq平台的高通量测序技术对添加益生菌和按照生产流程正常强化的轮虫、卤虫进行了菌群结构的分析和对比。添加外源益生菌的实验组轮虫和卤虫中的菌群物种多样性均明显高于对照组。在轮虫强化过程中,不同时期的对照组样品中菌群结构差异较明显,优势细菌种类变化较大。而添加外源益生菌后的各时期实验组轮虫菌群结构很相似,优势菌群的种类更为丰富,Lactococcus sp.、Pseudoalteromonas sp.和Alteromonas sp.等一直是各实验组中的优势细菌。在卤虫强化过程中,各对照组样品的菌群结构高度相似,优势细菌Cobetia sp.的相对丰度高达54%~65.2%。而在添加益生菌后,各实验组中的菌群结构仍高度相似,但Cobetia sp.的比例下降至4.3%~25.3%,最优势的细菌为Pseudoalteromonas sp.和Alteromonas sp.等几种,菌群结构中的物种均匀度更好。研究表明,在轮虫和卤虫强化过程中添加外源益生菌,能够改变生物饵料的菌群结构,使生物饵料中的细菌种类均匀度更好,并使菌群结构趋于稳定。

The microflora changes of rotifer and artemia with probiotics addition in Scophthalmus maximus larva breeding

Rotifer and artemia are indispensable living food in aquatic larval animal breeding. In order to evaluate bacterial communitiy change in rotifer and artemia enriching process with probiotics adding for turbot larva breeding, their microflora were analyzed using high-through sequencing technique based on illumina HiSeq platform. The results revealed that the diversity of experimental group with probiotics addition was higher than control group, which was the normal process in breeding. During rotifer enrichment process, the bacterial community structures of control group at different time were obviously different, and the dominant bacteria species varied greatly. However, bacterial community structures in different experimental groups were similar, and the dominant bacteria species were more diverse. Lactococcus sp., Pseudoalteromonas sp. and Alteromonas sp. as main bacteria appeared in each experimental group. In artemia enrichment process, bacterial communities of each control group were highly similar. The dominant bacteria of Cobetia sp. relative abundance reached 54%-65.2% in control group. With probiotic adding, bacterial community of each experimental group were still highly similar, but Cobetia sp. declined to 4.3%-25.3%, Pseudoalteromonas sp. and Alteromonas sp. became the new dominant bacteria. In conclusion, our findings showed that the bacterial community structure of living food for aquatic animal larva changed obviously and trended to be stable with probiotic adding, and the bacteria species in them became more uniform.