High occurrence of antibiotic resistance genes in intensive aquaculture of hybrid snakehead fish

Abstract

The increasing abundance of antibiotic resistance genes (ARGs), which are regarded as new pollutants, has raised public health concern. The use of antibiotics in aquaculture has promoted the evolution and spread of ARGs. The occurrence and abundance of ARGs in aquaculture has attracted extensive attention. However, the distribution and transmission of ARGs in aquaculture require further study. This study analyzed water and sediment from intensive culture of hybrid snakehead fish farm in Zhongshan, South China. Twenty-two types of ARGs were detected in all environmental samples. The relative abundance of sulfonamide resistance genes (sul1 and sul2) was the highest, ranging from 3.37×10-2 to 8.53×100 copies/16S rRNA gene. High occurrence of quinolones, phenicols, tetracycline resistance genes, and class 1 integrase gene (intI1) was also observed in pond water samples. This implies that pond water is one of the main reservoirs and origins of ARGs in the aquatic environment. Proteobacteria was the most abundant phylum in all the environmental samples, and its relative abundance ranged from 24.05% to 41.84%. Network and canonical correspondence analyses showed that a high abundance of ARGs (int1, sul1, sul2, qacEΔ1, aac6, and oqxA) was positively correlated with Proteobacteria, Cyanobacteria, and Bacteroidetes, and the abundance of Proteobacteria, Actinobacteria, and Patescibacteria was positively correlated with environmental factors (sulfide, nitrite nitrogen, pH, free chlorine, and ammonia nitrogen). These findings demonstrate the prevalence and persistence of ARGs in intensive fish farming in southern China. This suggests that ARG levels and microbiological community composition in aquaculture should be conventionally determined to assess potential risks to public health.

Effects of dietary astaxanthin on growth performance, immunity, and tissue composition in largemouth bass, Micropterus salmoides

“…Due to changing socio-economic landscapes, intensive aquaculture systems have been developed (Lin et al, 2023). Although intensive aquaculture systems have their advantages, they also bring various stress factors, including temperature fluctuations, water quality deterioration, intra-species competition, and overcrowding etc (Xie et al, 2008).…”

Detection of florfenicol resistance in opportunistic Acinetobacter spp. infections in rural Thailand

“…Florfenicol is widely used and, in some circumstances, reported to account for as much as 24.0% and 24.2% of all class C antimicrobials used during the weaning and fattening phases in pig rearing (Trevisi et al, 2022). Unsurprisingly, determinants of florfenicol resistance have been found in the environment associated with pig farms or in freshwater aquaculture (Fernández-Alarcón et al, 2010;Zhao et al, 2016;Zeng et al, 2019;Li et al, 2020;Fu et al, 2022;Wang et al, 2022;Lin et al, 2023). Several Ff resistance mechanisms have been identified, with the floR gene playing a significant role in conferring resistance.…”