Surface-attached and suspended bacterial community structure as affected by C/N ratios: relationship between bacteria and fish production.
Bacteria play crucial roles in the combined system of substrate addition and C/N control, which has been demonstrated to improve aquaculture production. However, the complexity of surface-attached bacteria on substrates and suspended bacteria in the water column hamper further application of this system. This study firstly applied this combined system into the culture of grass carp, and then explored the relationship between microbial complexes from surface-attached and suspended bacteria in this system and the production of grass carp. In addition, this study investigated bacterial community structures as affected by four C/N ratios using Illumina sequencing technology. The results demonstrated that the weight gain rate and specific growth rate of grass carp in the CN20 group (C/N ratio 20:1) were the highest (P < 0.05), and dietary supplementation of the microbial complex had positive effects on the growth of grass carp (P < 0.05). Sequencing data revealed that, (1) the proportions of Verrucomicrobiae and Rhodobacter (surface-attached), sediminibacterium (suspended), and emticicia (surface-attached and suspended) were much higher in the CN20 group compared with those in the other groups (P < 0.05); (2) Rhodobacter, Flavobacterium, Acinetobacter, Pseudomonas, Planctomyces, and Cloacibacterium might be important for the microbial colonization on substrates; (3) as the C/N ratio increased, proportions of Hydrogenophaga (surface-attached and suspended), Zoogloea, and Flectobacillus (suspended) increased, but proportions of Bacillus, Clavibacter, and Cellvibro (surface-attached and suspended) decreased. In summary, a combined system of substrate addition and C/N control increased the production of grass carp, and Verrucomicrobiae and Rhodobacter in the surface-attached bacterial community were potential probiotic bacteria that contributed to the enhanced growth of grass carp.
College of Life Science, South China Normal University, Zhongshan Road West 55, Guangzhou, 510631, China.|Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute of CAFS, XingYu Road, Guangzhou, 510380, China.
Ermeng
E
Yu
Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute of CAFS, XingYu Road, Guangzhou, 510380, China.
Jun
J
Xie
Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute of CAFS, XingYu Road, Guangzhou, 510380, China.
Jinlin
J
Wang
Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI, 96822, USA.
Harry
H
Ako
Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute of CAFS, XingYu Road, Guangzhou, 510380, China.
Guangjun
G
Wang
College of Life Science, South China Normal University, Zhongshan Road West 55, Guangzhou, 510631, China. chenzhh@scnu.edu.cn.
Zhanghe
Z
Chen
BGI-Shenzhen, Main Building 11/F, Shenzhen, 518083, China.
Yongfeng
Y
Liu
D000821:Animal Feed; D000818:Animals; D017756:Aquaculture / Q000379:methods*; D001419:Bacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002244:Carbon / Q000008:administration & dosage / Q000378:metabolism*; D002347:Carps / Q000254:growth & development* / Q000382:microbiology*; D019587:Dietary Supplements; D005516:Food Microbiology; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods; D009584:Nitrogen / Q000008:administration & dosage / Q000378:metabolism*; D010802:Phylogeny; D019936:Probiotics; D017422:Sequence Analysis, DNA; D014871:Water Microbiology
D002244:Carbon; D009584:Nitrogen
Bacterial community structure; C/N ratio; Grass carp; Illumina sequencing; Surface-attached