AUTHOR=Lastauskienė Eglė , Valskys Vaidotas , Stankevičiūtė Jonita , Kalcienė Virginija , Gėgžna Vilmantas , Kavoliūnas Justinas , Ružauskas Modestas , Armalytė Julija 

TITLE=The Impact of Intensive Fish Farming on Pond Sediment Microbiome and Antibiotic Resistance Gene Composition

JOURNAL=Frontiers in Veterinary Science

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2021.673756

DOI=10.3389/fvets.2021.673756

ISSN=2297-1769

ABSTRACT=Aquaculture is a fast-growing animal food sector, and freshwater fish farming is particularly common in Central and Eastern Europe. As the biodiversity of fishery ponds is changed towards fulfilling the industrial needs, precautions should be taken to keep the system sustainable and protect the adjacent environment from possible damage. Due to risk of infectious diseases, antibiotics are used in aquaculture production systems. The constant exposure to antimicrobials can contribute to the rise of antibiotic resistance in aquaculture products and the adjacent ecosystems, with possibility of dissemination to the wider environment as well as between animals and humans. Even though previous studies have found antibiotic resistance genes in the sediments and water of farming ponds, the tendency and direction of spreading is not clear yet. 
The objective of this project was to evaluate the influence of intensive fish farming on the condition of water bodies used for the aquaculture and the environment, concentrating on combined detection of antibiotic and heavy metal contamination, microorganism diversity and the spread of antibiotic resistance genes. The comparison of the sediments in the fishery ponds as well as upstream and downstream could show the impact of the aquaculture on the surrounding water ecosystems as well as the possibility of transferring the antibiotic resistance genes to the human hosts.
The sediment samples collected from several locations in fishery ponds as well as locations upstream and downstream did not show significantly elevated heavy metal concentrations and no substantial veterinary antibiotic pollution. From the antibiotic resistance genes tested, the presence of aminoglycoside and β-lactam resistance determinants as well as the presence of integrons could be of concern for the possibility of transfer to humans. However, despite the lack of heavy metal and antibiotic pollution, the sediments showed toxicity, the cause of which should be explored more