池塘内循环流水养殖下太湖鲂鲌(翘嘴鲌(♀)×三角鲂(♂))肠道微生物群落变化的研究

为研究池塘内循环流水养殖(In-pond Raceway, IPR)模式下太湖鲂鲌(翘嘴鲌(♀)×三角鲂(♂))肠道微生物群落结构的变化,以传统池塘养殖作为对照组,采用16SrRNA高通量测序方法分析了IPR养殖模式下太湖鲂鲌肠道的菌群结构及环境水体微生物多样性的变化。试验结果表明, IPR模式下太湖鲂鲌肠道微生物群落发生了明显的变化,在门分类水平,梭杆菌门(Fusobacteria)成为绝对优势菌,所占丰度为92.47%;对照组的优势菌由梭杆菌门、变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)组成,三者所占的丰度分别为34.45%、33.30%和21.30%。在养殖水环境中,两种养殖模式的微生物群落数均大于肠道样本,且二者优势菌不同;IPR水环境的优势菌为蓝细菌(Cyanobacteria,36.53%),其次为放线菌门(Actinobacteria,24.67%);对照组水体中的优势菌为放线菌门和变形菌门,分别占细菌总数的38.99%和28.15%。多样性指数结果表明,水环境中的微生物群落Shannon多样性指数、Chao1指数高于肠道样本,IPR养殖对象肠道微生物群落多样性最低。本研究结果揭示,池塘内循环流水高密度养殖模式下,太湖鲂鲌的肠道微生物结构发生了一定的改变,微生物群落多样性降低,应注意该模式下养殖对象的肠道健康,加强养殖管理。

ON CHANGES OF INTESTINAL MICROBIOTA OF A NEW HYBRID STRAIN OF (FEMALE CULTER ALBURNUS)×(MALE MEGALOBRAMA TERMINALIS) REARED IN IN-POND RACEWAY AQUACULTURE SYSTEM

To study the changes of intestinal microbiota in a new hybrid strain of (female Culter alburnus Basilewsky×male Megalobrama terminalis) reared in an in-pond race (IPR) aquaculture system, 16S rRNA high-throughput sequencing method was used to analyze the microflora structure and diversity of intestinal tract and water samples while the common pond was used as a control group. Results show that the microbial structure of intestinal tract changed obviously in the IPR group and it was strongly dominated by Fusobacteria at phylum level, which occupied 92.47% of the total species. However, three dominant phyla were found in the control group, including Fusobacteria, Proteobacteria, and Firmicutes, with the abundance of 34.45%, 33.30% and 21.30%, respectively. The numbers of microflora in water samples were higher than that of intestinal samples, and their dominant phylum was different. Cyanobacteria was the most abundant phylum in the water of IPR, the relative abundance was 36.53%. Actinobacteria was the second dominant phylum, 24.67%. In contrast, Actinobacteria and Proteobacteria were the most abundant phyla in the control group and their relative abundances were 38.99% and 28.15%, respectively. The diversity index indicates that the Shannon index and Chao1 index were higher in water samples than in that of intestinal tract, and the value of the diversity index in the IPR intestinal sample was the lowest of the all samples. Results reveal that the structure of intestinal microflora in the IPR changed to a certain extent and the diversity of bacterial communities decreased obviously. Attention shall be paid to the intestinal health and culturing management of the IPR.