Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms

Pollutants and pathogens in aquaculture systems may cause economic losses and threaten public health. Yet, the risks associated with microbiological contaminants and their relationship with environmental factors remain largely unknown. In this study, two typical eel farms in southeast China were cho...

Full description

Saved in:
Bibliographic Details
Main Authors: Jing-Ying Lai, Hui-Rong Lin, Xiao-Hui Sun, Gong-Ren Hu, Rui-Lian Yu, Jia-Qi Li
Format: Article
Language:English
Published: MDPI AG 2025-07-01
Series:Microorganisms
Subjects:
Online Access:https://www.mdpi.com/2076-2607/13/7/1624
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849252057954910208
author Jing-Ying Lai
Hui-Rong Lin
Xiao-Hui Sun
Gong-Ren Hu
Rui-Lian Yu
Jia-Qi Li
author_facet Jing-Ying Lai
Hui-Rong Lin
Xiao-Hui Sun
Gong-Ren Hu
Rui-Lian Yu
Jia-Qi Li
author_sort Jing-Ying Lai
collection DOAJ
description Pollutants and pathogens in aquaculture systems may cause economic losses and threaten public health. Yet, the risks associated with microbiological contaminants and their relationship with environmental factors remain largely unknown. In this study, two typical eel farms in southeast China were chosen for investigation of water quality and microbial community in the treatment processes. It was found that flocculant addition can only effectively reduce total phosphorus (TP) in both farms. However, excessive total nitrogen (TN) was found (6.16 mg/L and 6.74 mg/L, respectively). NH<sub>4</sub><sup>+</sup> (3.98 mg/L) was the main nitrogen pollutant in QR farm, while NO<sub>3</sub><sup>−</sup> (3.81 mg/L) and NO<sub>2</sub><sup>−</sup> (1.22 mg/L) were the main nitrogen pollutants in ZJ farm. The treatment processes could not effectively remove nitrogen pollution, and the abundance of nitrogen functional bacteria was low. NO<sub>2</sub><sup>−</sup> was positively correlated with Verrucomicrobiota (<i>p</i> < 0.05). NH<sub>4</sub><sup>+</sup> and TN were significantly negatively correlated with Nitrospirota and <i>unclassified_f_Anaerolineaceae</i>, respectively (<i>p</i> < 0.05). Some typical pathogens associated with aquaculture (e.g., <i>Lactococcus</i>) and human beings (e.g., <i>Escherichia-Shigella</i>,) were found in the systems. This study proposes suggestions for aquaculture tailwater by analyzing the shortcomings of the existing treatment processes. Meanwhile, it offers certain support for the prevention of pathogen risks in aquaculture systems.
format Article
id doaj-art-1be51ab716e7436d87b5cb75450ba7e8
institution Kabale University
issn 2076-2607
language English
publishDate 2025-07-01
publisher MDPI AG
record_format Article
series Microorganisms
spelling doaj-art-1be51ab716e7436d87b5cb75450ba7e82025-08-20T03:56:45ZengMDPI AGMicroorganisms2076-26072025-07-01137162410.3390/microorganisms13071624Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel FarmsJing-Ying Lai0Hui-Rong Lin1Xiao-Hui Sun2Gong-Ren Hu3Rui-Lian Yu4Jia-Qi Li5College of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaCollege of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaCollege of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaCollege of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaCollege of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaCollege of Chemical Engineering, Huaqiao University, Xiamen 361021, ChinaPollutants and pathogens in aquaculture systems may cause economic losses and threaten public health. Yet, the risks associated with microbiological contaminants and their relationship with environmental factors remain largely unknown. In this study, two typical eel farms in southeast China were chosen for investigation of water quality and microbial community in the treatment processes. It was found that flocculant addition can only effectively reduce total phosphorus (TP) in both farms. However, excessive total nitrogen (TN) was found (6.16 mg/L and 6.74 mg/L, respectively). NH<sub>4</sub><sup>+</sup> (3.98 mg/L) was the main nitrogen pollutant in QR farm, while NO<sub>3</sub><sup>−</sup> (3.81 mg/L) and NO<sub>2</sub><sup>−</sup> (1.22 mg/L) were the main nitrogen pollutants in ZJ farm. The treatment processes could not effectively remove nitrogen pollution, and the abundance of nitrogen functional bacteria was low. NO<sub>2</sub><sup>−</sup> was positively correlated with Verrucomicrobiota (<i>p</i> < 0.05). NH<sub>4</sub><sup>+</sup> and TN were significantly negatively correlated with Nitrospirota and <i>unclassified_f_Anaerolineaceae</i>, respectively (<i>p</i> < 0.05). Some typical pathogens associated with aquaculture (e.g., <i>Lactococcus</i>) and human beings (e.g., <i>Escherichia-Shigella</i>,) were found in the systems. This study proposes suggestions for aquaculture tailwater by analyzing the shortcomings of the existing treatment processes. Meanwhile, it offers certain support for the prevention of pathogen risks in aquaculture systems.https://www.mdpi.com/2076-2607/13/7/1624nitrogen pollutionaquaculture wastewater treatmentpathogensprocess optimization
spellingShingle Jing-Ying Lai
Hui-Rong Lin
Xiao-Hui Sun
Gong-Ren Hu
Rui-Lian Yu
Jia-Qi Li
Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
Microorganisms
nitrogen pollution
aquaculture wastewater treatment
pathogens
process optimization
title Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
title_full Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
title_fullStr Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
title_full_unstemmed Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
title_short Characterization, Microbial Community Structure, and Pathogen Occurrence in Two Typical Eel Farms
title_sort characterization microbial community structure and pathogen occurrence in two typical eel farms
topic nitrogen pollution
aquaculture wastewater treatment
pathogens
process optimization
url https://www.mdpi.com/2076-2607/13/7/1624
work_keys_str_mv AT jingyinglai characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms
AT huironglin characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms
AT xiaohuisun characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms
AT gongrenhu characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms
AT ruilianyu characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms
AT jiaqili characterizationmicrobialcommunitystructureandpathogenoccurrenceintwotypicaleelfarms