# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 7214 | 0 | 0.9925 | Long-term application of fresh and composted manure increase tetracycline resistance in the arable soil of eastern China. The aim of this study was to compare the occurrence, abundance, and diversity of tetracycline resistance genes (tet) in agricultural soils after 6 years' application of fresh or composted swine manure. Soil samples were collected from fresh or composted manure-treated farmland at three depths (0-5 cm, 5-10 cm, and 10-20 cm). Nine classes of tet genes [tetW, tetB(P), tetO, tetS, tetC, tetG, tetZ, tetL, and tetX] were detected; tetG, tetZ, tetL, and tetB(P) were predominant in the manure-treated soil. The abundances of tetB(P), tetW, tetC, and tetO were reduced, while tetG and tetL were increased by fertilizing with composted versus fresh manure; thus, the total abundance of tet genes was not significantly reduced by compost manuring. tetG was the most abundant gene in manure-treated soil; the predominant tetG genotypes shared high homology with pathogenic bacteria. The tetG isolates were more diverse in soils treated with fresh versus composted manure, although the residual tet genes in composted manure remain a pollutant and produce a different influence on the tet gene resistome in field soil. | 2015 | 25460961 |
| 7211 | 1 | 0.9924 | Contribution of Manure-Spreading Operations to Bioaerosols and Antibiotic Resistance Genes' Emission. Manure spreading from farm animals can release antibiotic-resistant bacteria (ARB) carrying antimicrobial resistance genes (ARGs) into the air, posing a potential threat to human and animal health due to the intensive use of antibiotics in the livestock industry. This study analyzed the effect of different manure types and spreading methods on airborne bacterial emissions and antibiotic resistance genes in a controlled setting. Cow, poultry manure, and pig slurry were spread in a confined environment using two types of spreaders (splash plate and dribble bar), and the resulting emissions were collected before, during, and after spreading using high-volume air samplers coupled to a particle counter. Total bacteria, fecal indicators, and a total of 38 different subtypes of ARGs were further quantified by qPCR. Spreading poultry manure resulted in the highest emission rates of total bacteria (10(11) 16S gene copies/kg manure spread), Archaea (10(6) 16S gene copies/kg manure), Enterococcus (10(5) 16S gene copies/kg manure), and E. coli (10(4) 16S gene copies/kg manure), followed by cow manure and pig slurry with splash plates and the dribble bar. Manure spreading was associated with the highest rates of airborne aminoglycoside genes for cow and poultry (10(6) gene copies/kg manure), followed by pig slurry (10(4) gene copies/kg manure). This study shows that the type of manure and spreading equipment can affect the emission rates of airborne bacteria, and ARGs. | 2023 | 37512969 |
| 3481 | 2 | 0.9924 | Antibiotics and Antibiotic Resistance Genes in Sediment of Honghu Lake and East Dongting Lake, China. Sediment is an ideal medium for the aggregation and dissemination of antibiotics and antibiotic resistance genes (ARGs). The levels of antibiotics and ARGs in Honghu Lake and East Dongting Lake of central China were investigated in this study. The concentrations of eight antibiotics (four sulfonamides and four tetracyclines) in Honghu Lake were in the range 90.00-437.43 μg kg(-1) (dry weight (dw)) with mean value of 278.21 μg kg(-1) dw, which was significantly higher than those in East Dongting Lake (60.02-321.04 μg kg(-1) dw, mean value of 195.70 μg kg(-1) dw). Among the tested three sulfonamide resistance genes (sul) and eight tetracycline resistance genes (tet), sul1, sul2, tetA, tetC, and tetM had 100 % detection frequency in sediment samples of East Dongting Lake, while only sul1, sul2, and tetC were observed in all samples of Honghu Lake. The relative abundance of sul2 was higher than that of sul1 at p < 0.05 level in both lakes. The relative abundance of tet genes in East Dongting Lake was in the following order: tetM > tetB > tetC > tetA. The relative abundance of sul1, sul2, and tetC in East Dongting Lake was significantly higher than those in Honghu Lake. The abundance of background bacteria may play an important role in the horizontal spread of sul2 and tetC genes in Honghu Lake and sul1 in East Dongting Lake, respectively. Redundancy analysis indicated that tetracyclines may play a more important role than sulfonamides in the abundance of sul1, sul2, and tetC gens in Honghu Lake and East Dongting Lake. | 2016 | 27418176 |
| 7167 | 3 | 0.9924 | Occurrence and distribution of antibiotic pollution and antibiotic resistance genes in seagrass meadow sediments based on metagenomics. Seagrass meadows are one of the most important coastal ecosystems that provide essential ecological and economic services. The contamination levels of antibiotic and antibiotic resistance genes (ARGs) in coastal ecosystems are severely elevated owing to anthropogenic disturbances, such as terrestrial input, aquaculture effluent, and sewage discharge. However, few studies have focused on the occurrence and distribution of antibiotics and their corresponding ARGs in this habitat. Thus, we investigated the antibiotic and ARGs profiles, microbial communities, and ARG-carrying host bacteria in typical seagrass meadow sediments collected from Swan Lake, Caofeidian shoal harbor, Qingdao Bay, and Sishili Bay in the Bohai Sea and northern Yellow Sea. The total concentrations of 30 detected antibiotics ranged from 99.35 to 478.02 μg/kg, tetracyclines were more prevalent than other antibiotics. Metagenomic analyses showed that 342 ARG subtypes associated with 22 ARG types were identified in the seagrass meadow sediments. Multidrug resistance genes and RanA were the most dominant ARG types and subtypes, respectively. Co-occurrence network analysis revealed that Halioglobus, Zeaxanthinibacter, and Aureitalea may be potential hosts at the genus level, and the relative abundances of these bacteria were higher in Sishili Bay than those in other areas. This study provided important insights into the pollution status of antibiotics and ARGs in typical seagrass meadow sediments. Effective management should be performed to control the potential ecological health risks in seagrass meadow ecosystems. | 2024 | 38782270 |
| 7160 | 4 | 0.9923 | High-throughput profiling of antibiotic resistance genes in the Yellow River of Henan Province, China. Profiling antibiotic resistance genes (ARGs) in the Yellow River of China's Henan Province is essential for understanding the health risks of antibiotic resistance. The profiling of ARGs was investigated using high-throughput qPCR from water samples in seven representative regions of the Yellow River. The absolute and relative abundances of ARGs and moble genetic elements (MGEs) were higher in summer than in winter (ANOVA, p < 0.001). The diversity and abundance of ARGs were higher in the Yellow River samples from PY and KF than the other sites. Temperature (r = 0.470 ~ 0.805, p < 0.05) and precipitation (r = 0.492 ~ 0.815, p < 0.05) positively influenced the ARGs, while pH had a negative effect (r = - 0.462 ~ - 0.849, p < 0.05). Network analysis indicated that the pathogenic bacteria Rahnella, Bacillus, and Shewanella were the possible hub hosts of ARGs, and tnpA1 was the potential MGE hub. These findings provide insights into the factors influencing ARG dynamics and the complex interaction among the MGEs, pathogenic bacteria and environmental parameters in enriching ARGs in the Yellow River of Henan Province. | 2024 | 39080455 |
| 8030 | 5 | 0.9923 | Application of manure containing tetracyclines slowed down the dissipation of tet resistance genes and caused changes in the composition of soil bacteria. Manure application contributes to the increased environmental burden of antibiotic resistance genes (ARGs). We investigated the response of tetracycline (tet) resistance genes and bacterial taxa to manure application amended with tetracyclines over two months. Representative tetracyclines (oxytetracycline, chlorotetracycline and doxycycline), tet resistance genes (tet(M), tet(O), tet(W), tet(S), tet(Q) and tet(X)) and bacterial taxa in the untreated soil, +manure, and +manure+tetracyclines groups were analyzed. The abundances of all tet resistance genes in the +manure group were significantly higher than those in the untreated soil group on day 1. The abundances of all tet resistance genes (except tet(Q) and tet(X)) were significantly lower in the +manure group than those in the +manure+tetracyclines group on day 30 and 60. The dissipation rates were higher in the +manure group than those in the +manure+tetracyclines group. Disturbance of soil bacterial community composition imposed by tetracyclines was also observed. The results indicated that tetracyclines slowed down the dissipation of tet resistance genes in arable soil after manure application. Application of manure amended with tetracyclines may provide a significant selective advantage for species affiliated to the taxonomical families of Micromonosporaceae, Propionibacteriaceae, Streptomycetaceae, Nitrospiraceae and Clostridiaceae. | 2018 | 28898804 |
| 7163 | 6 | 0.9923 | Prevalence of antibiotic resistance genes and bacterial pathogens in long-term manured greenhouse soils as revealed by metagenomic survey. Antibiotic resistance genes (ARGs), human pathogenic bacteria (HPB), and HPB carrying ARGs pose a high risk to soil ecology and public health. Here, we used a metagenomic approach to investigate their diversity and abundance in chicken manures and greenhouse soils collected from Guli, Pulangke, and Hushu vegetable bases with different greenhouse planting years in Nanjing, Eastern China. There was a positive correlation between the levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in manures and greenhouse soils. In total, 156.2–5001.4 μg/kg of antibiotic residues, 22 classes of ARGs, 32 HPB species, and 46 species of HPB carrying ARGs were found. The highest relative abundance was tetracycline resistance genes (manures) and multidrug resistance genes (greenhouse soils). The dominant HPB and HPB carrying ARGs in the manures were Bacillus anthracis, Bordetella pertussis, and B. anthracis (sulfonamide resistance gene, sul1), respectively. The corresponding findings in greenhouse soils were Mycobacterium tuberculosis and M. ulcerans, M. tuberculosis (macrolide-lincosamide-streptogramin resistance protein, MLSRP), and B. anthracis (sul1), respectively. Our findings confirmed high levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in the manured greenhouse soils compared with those in the field soils, and their relative abundance increased with the extension of greenhouse planting years. | 2015 | 25514174 |
| 8109 | 7 | 0.9922 | The fate of antibiotic resistance genes and their influential factors in swine manure composting with sepiolite as additive. Manures are storages for antibiotic resistance genes (ARGs) entering the environment. This study investigated the effects of adding sepiolite at 0%, 2.5%, 5%, and 7.5% (CK, T1, T2, and T3, respectively) on the fates of ARGs during composting. The relative abundances (RAs) of the total ARGs in CK and T3 decreased by 0.23 and 0.46 logs, respectively, after composting. The RAs of 10/11 ARGs decreased in CK, whereas they all decreased in T3. The reduction in the RA of the total mobile genetic elements (MGEs) was 1.26 times higher in T3 compared with CK after composting. The bacterial community accounted for 47.93% of the variation in the abundances of ARGs. Network analysis indicated that ARGs and MGEs shared potential host bacteria (PHB), and T3 controlled the transmission of ARGs by reducing the abundances of PHB. Composting with 7.5% sepiolite is an effective strategy for reducing the risk of ARGs proliferating. | 2022 | 35063626 |
| 7156 | 8 | 0.9922 | Effect of antibiotics, antibiotic-resistant bacteria, and extracellular antibiotic resistance genes on the fate of ARGs in marine sediments. Surface runoff is a prevalent source via which emerging pollutants (i.e., antibiotics, antibiotic-resistant bacteria (ARB), and antibiotic resistance genes (ARGs)) enter marine sediments. However, few studies have investigated the effect of emerging pollutants on the fate of ARGs in marine sediments. Therefore, three systems were established to measure the relative abundances of four common ARGs (i.e., bla(TEM), tetA, tetC, and aphA) and the integron-integrase gene (intI1) after exposure to emerging pollutants in marine sediments from the Bohai Sea, the Yellow Sea, the East China Sea, and the South China Sea in China. The results revealed that antibiotic exposure could decrease the relative abundance of most ARGs (including bla(TEM), tetA, and tetC) in these marine sediment samples. The exceptions were the relative abundance of bla(TEM) in the Bohai Sea marine sediments under ampicillin exposure and tetC in the Yellow Sea marine sediments under tetracycline exposure, which increased significantly. Among marine sediments challenged with ARB, the relative abundance of aphA in all four marine sediments displayed a decreasing trend, whereas the abundances of bla(TEM) and tetA in the marine sediments from the Bohai Sea and the South China Sea showed an increasing trend. The relative abundance of tetA in the marine sediments from the Yellow Sea and the East China Sea dropped markedly when exposed to extracellular ARG (eARG). Significant changes in bla(TEM) abundance were observed in the four marine sediments under eARG exposure. Gene aphA abundance showed the same trend as the intI1 abundance. IntI1 showed a decreasing trend under the exposure of antibiotic, ARB, or eARG, apart from the East and the South China Sea marine sediments under ampicillin conditions and the South China Sea marine sediments under RP4 plasmid condition. These findings suggest that dosing with emerging pollutants does not increase ARG abundance in marine sediments. | 2023 | 37245825 |
| 7162 | 9 | 0.9921 | Dissemination of antibiotic resistance genes and human pathogenic bacteria from a pig feedlot to the surrounding stream and agricultural soils. The dissemination of antibiotic resistance genes (ARGs), human pathogenic bacteria (HPB), and antibiotic-resistant HPB (ARHPB) from animal feedlot to nearby environment poses a potentially high risk to environmental ecology and public health. Here, a metagenomic analysis was employed to explore the dissemination of ARGs, HPB, and ARHPB from a pig feedlot to surrounding stream and agricultural soils. In total, not detectable (ND)-1,628.4 μg/kg of antibiotic residues, 18 types of ARGs, 48 HPB species, and 216 ARB isolates were detected in all samples. Antibiotic residues from pig feedlot mainly migrated into stream sediments and greenhouse soil. The dominant ARGs and HPB species from pig feedlot spread into stream sediments (tetracycline resistance genes, Clostridium difficile, and Mycobacterium tuberculosis), stream water (multidrug resistance (MDR) genes, Shigella flexneri, and Bordetella pertussis), and greenhouse soil (MDR genes, Bacillus anthracis, and Brucella melitensis). It is concerning that 54.4% of 216 ARB isolates from all samples were potential ARHPB species, and genome sequencing and functional annotation of 4 MDR HPB isolates showed 9 ARG types. Our findings revealed the potential migration and dissemination of antibiotic residues, ARGs, HPB, and ARHPB from pig feedlot to surrounding stream and agricultural soils via pig sewage discharge and manure fertilization. | 2018 | 29860105 |
| 7234 | 10 | 0.9921 | Urban and agriculturally influenced water contribute differently to the spread of antibiotic resistance genes in a mega-city river network. The widespread of water borne antibiotic resistance genes (ARGs) represents a growing threat to the health of millions of people. Our study detected the relative abundances of 10 ARG subtypes in the Shanghai river network, where the major ARG components were strB, sul1, and ermB. These ARGs were significantly enriched by the combined sewage, tail water from urban wastewater treatment plant and runoff from agricultural areas, which reached the Suzhou (SZ), Dianpu (DP), and Huangpu (HP) River, respectively (one-way ANOVA, P < 0.01). The target ARGs were distributed in varying patterns across different rivers. bla(CTX-M) and bla(TEM) contributed to the increase of total ARGs in the rivers influenced by urban sources, particularly in the SZ River, whose distribution of ARGs was significantly related to that of the confluence of the whole river network (Mantel test, P < 0.01). The bacterial community was closely structured with ARGs and potential pathogenic bacteria's association with target ARGs became significant in downstream samples (Procrustes test, P = 0.03). Water near urban wastewater fallouts was observed to have the highest content of intl1 in the DP River, whose downstream samples' intl -ARG relationship fitted the same regression model as that of the network confluence (R = 0.84, P < 0.001). The amelioration of river water quality does not reduce ARGs, but may affect their distributional patterns in the river network in Shanghai. | 2019 | 31009830 |
| 7219 | 11 | 0.9921 | Occurrence and human exposure risk of antibiotic resistance genes in tillage soils of dryland regions: A case study of northern Ningxia Plain, China. Agricultural soils are important source and sink of antibiotic resistance genes (ARGs). However, little is known about the fate of ARGs in dryland soils, while its human exposure risks were seriously overlooked. Taking the northern Ningxia Plain as a case, this study explored the occurrence of ARGs and its relationship with mobile genetic elements (MGEs), pathogens, and environmental factors. Furthermore, the concentrations of airborne ARGs by soil wind erosion and the human exposure doses of soil ARGs were evaluated. The results showed the abundances of different regions ranged from 4.0 × 10(5) to 1.6 × 10(6) copies/g. Soil ARGs are driven by MGEs, but multiply impacted by soil properties, nutrition, and bacterial community. Vibrio metschnikovii, Acinetobacter schindleri, and Serratia marcescens are potential pathogenic hosts for ARGs. Further exploration revealed the concentration of ARGs loaded in dust by soil wind erosion reached more than 10(5) copies/m(3), which were even higher than those found in sewage treatment plants and hospitals. Skin contact is the primary route of ARGs exposure, with a maximum dose of 24071.33 copies/kg/d, which is largely attributed to ARGs loaded in dust. This study bridged the gap on ARGs in dryland soils, and provided reference for human exposure risk assessment of soil ARGs. | 2024 | 39276744 |
| 8019 | 12 | 0.9920 | In-feed antibiotic use changed the behaviors of oxytetracycline, sulfamerazine, and ciprofloxacin and related antibiotic resistance genes during swine manure composting. The dynamics of oxytetracycline (OTC), sulfamerazine (SM1), ciprofloxacin (CIP) and related antibiotic resistance genes (ARGs) during swine manure composting were compared between manure collected from swine fed a diet containing these three antibiotics (T(D)) and manure directly spiked with these drugs (T(S)). The composting removal efficiency of OTC (94.9 %) and CIP (87.8 %) in the T(D) treatment was significantly higher than that of OTC (83.8 %, P < 0.01) and CIP (83.9 %, P < 0.05) in the T(S) treatment, while SM1 exhibited no significant difference (P > 0.05) between the two treatments. Composting effectively reduced the majority of ARGs in both T(D) and T(S) types of manure, especially tetracycline resistance genes (TRGs). Compared with the T(S) treatment, the abundance of some ARGs, such as tetG, qepA, sul1 and sul2, increased dramatically up to 309-fold in the T(D) treatment. The microbial composition of the composting system changed significantly during composting due to antibiotic feeding. Redundancy analysis suggested that the abundance of ARGs had a considerable impact on alterations in the physicochemical parameters (C/N, pH and temperature) and bacterial communities (Actinobacteria, Proteobacteria and Firmicutes) during the composting of swine manure. | 2021 | 33254754 |
| 3480 | 13 | 0.9920 | Short-term inhalation exposure evaluations of airborne antibiotic resistance genes in environments. Antibiotic resistance is a sword of Damocles that hangs over humans. In regards to airborne antibiotic resistance genes (AARGs), critical knowledge gaps still exist in the identification of hotspots and quantification of exposure levels in different environments. Here, we have studied the profiles of AARGs, mobile genetic elements (MGEs) and bacterial communities in various atmospheric environments by high throughput qPCR and 16S rRNA gene sequencing. We propose a new AARGs exposure dose calculation that uses short-term inhalation (STI). Swine farms and hospitals were high-risk areas where AARGs standardised abundance was more abundant than suburbs and urban areas. Additionally, resistance gene abundance in swine farm worker sputum was higher than that in healthy individuals in other environments. The correlation between AARGs with MGEs and bacteria was strong in suburbs but weak in livestock farms and hospitals. STI exposure analysis revealed that occupational intake of AARGs (via PM(10)) in swine farms and hospitals were 110 and 29 times higher than in suburbs, were 1.5 × 10(4), 5.6 × 10(4) and 5.1 × 10(2) copies, i.e., 61.9%, 75.1% and 10.7% of the overall daily inhalation intake, respectively. Our study comprehensively compares environmental differences in AARGs to identify high-risk areas, and forwardly proposes the STI exposure dose of AARGs to guide risk assessment. | 2022 | 35717091 |
| 3482 | 14 | 0.9920 | Metagenomic profiling of ARGs in airborne particulate matters during a severe smog event. Information is currently limited regarding the distribution of antibiotic resistance genes (ARGs) in smog and their correlations with airborne bacteria. This study characterized the diversity and abundance of ARGs in the particulate matters (PMs) of severe smog based on publicly available metagenomic data, and revealed the occurrence of 205 airborne ARG subtypes, including 31 dominant ones encoding resistance to 11 antibiotic types. Among the detectable ARGs, tetracycline, β-lactam and aminoglycoside resistance genes had the highest abundance, and smog and soil had similar composition characteristics of ARGs. During the smog event, the total abundance of airborne ARGs ranged from 4.90 to 38.07ppm in PM(2.5) samples, and from 7.61 to 38.49ppm in PM(10) samples, which were 1.6-7.7 times and 2.1-5.1 times of those in the non-smog day, respectively. The airborne ARGs showed complicated co-occurrence patterns, which were heavily influenced by the interaction of bacterial community, and physicochemical and meteorological factors. Lactobacillus and sulfonamide resistance gene sul1 were determined as keystones in the co-occurrence network of microbial taxa and airborne ARGs. The results may help to understand the distribution patterns of ARGs in smog for the potential health risk evaluation. | 2018 | 29751438 |
| 7228 | 15 | 0.9920 | Proliferation of antibiotic resistance genes in coastal recirculating mariculture system. The abuse of antibiotics has caused the propagation of antibiotic resistance genes (ARGs) in aquaculture systems. Although the recirculating systems have been considered as a promising approach for preventing the coastal water pollution of antibiotics and ARG, rare information is available on the distribution and proliferation of ARGs in the recirculating mariculture system. This study firstly investigated the proliferation of ARGs in coastal recirculating mariculture systems. Ten subtypes of ARGs including tet (tetB, tetG, tetX), sul (sul1, sul2), qnr (qnrA, qnrB, qnrS), and erm (ermF, ermT) were detected. The absolute abundances of the ARGs detected in the mariculture farm were more than 1 × 10(4) copies/mL. The sulfonamide resistance genes (sul1 and sul2) were the most abundant ARGs with the abundance of 3.5 × 10(7)-6.5 × 10(10) copies/mL. No obvious correlation existed between the antibiotics and ARGs. Some bacteria were positively correlated with two or more ARGs to indicate the occurrence of multidrug resistance. The fluidized-bed biofilter for wastewater treatment in the recirculating system was the main breeding ground for ARGs while the UV sterilization process could reduce the ARGs. The highest flux of ARGs (6.5 × 10(21) copies/d) indicated that the discharge of feces and residual baits was the main gateway for ARGs in the recirculating mariculture system to enter the environments. | 2019 | 30826609 |
| 8026 | 16 | 0.9920 | A comparison of antibiotics, antibiotic resistance genes, and bacterial community in broiler and layer manure following composting. Animal manure is an important source of antibiotics and antibiotic resistance genes (ARGs) in the environment. However, the difference of antibiotic residues and ARG profiles in layer and broiler manure as well as their compost remains unexplored. In this study, we investigated the profiles of twelve antibiotics, seventeen ARGs, and class 1 integrase gene (intI1) in layer and broiler manure, and the corresponding compost at large-scale. Compared with layer manure, broiler manure exhibited approximately six times more residual tetracyclines, especially chlortetracycline. The relative abundances of qnrS and ermA genes in broiler manure were significantly higher than those in layer manure. The concentration of tetracyclines not only had a significantly positive correlation with tetracycline resistance genes (tetA and tetC) but was also positively correlated with quinolone resistance (qepA, qnrB, and qnrS) and macrolide resistance (ermA and ermT). Most ARGs in manure were reduced after composting. However, the relative abundance of sulfonamide resistance gene sul1 increased up to 2.41% after composting, which was significantly higher than that of broiler (0.41%) and layer (0.62%) manure. The associated bacterial community was characterized by high-throughput 16S rRNA gene sequencing. The relative abundances of thermophilic bacteria had significant positive correlations with the abundance of sul1 in compost. The composting has a significant impact on the ARG-associated gut microbes in poultry manure. Variation partitioning analysis indicated that the change of bacterial community compositions and antibiotics contributed partially to the shift in ARG profiles. The results indicate that at industry-scale production broiler manure had more antibiotics and ARGs than layer manure did, and composting decreased most ARG abundances in poultry manure except for sulfonamide resistance genes. | 2021 | 33219508 |
| 8108 | 17 | 0.9919 | Insights into the beneficial effects of woody peat for reducing abundances of antibiotic resistance genes during composting. Antibiotic resistance genes (ARGs) in manure endangered human health, while heavy metals in manure will pose selective pressure on ARGs. This study explored the effects on ARGs of adding woody peat during composting at different ratios (0 (CK), 5% (T1), and 15% (T2)). After composting, the relative abundances of 8/11 ARGs were 6.97-38.09% and 10.73-54.31% lower in T1 and T2, respectively, than CK. The bioavailable Cu content was 1.40% and 18.40% lower in T1 and T2, respectively, than CK. Network analysis showed that ARGs, mobile genetic elements (MGEs), and metal resistance genes possessed common potential host bacteria, such as Streptococcus, Dietzia, and Corynebacterium_1. Environmental factors, especially bioavailable Cu, and MGEs accounted for 80.75% of the changes in the abundances of ARGs. In conclusion, 15% Woody peat is beneficial to decrease the bioavailable Cu content and weaken horizontal gene transfer for controlling the spread of ARGs during composting. | 2021 | 34534940 |
| 6856 | 18 | 0.9919 | Effects of the coexistence of antibiotics and heavy metals on the fate of antibiotic resistance genes in chicken manure and surrounding soils. Both heavy metals and antibiotics exert selection pressure on bacterial resistance, and as they are commonly co-contaminated in the environment, they may play a larger role in bacterial resistance. This study examined how breeding cycles affect antibiotic resistance genes (ARGs) in chicken manure and the surrounding topsoils at 20, 50, 100, 200, and 300 m from twelve typical laying hen farms in the Ningxia Hui Autonomous Region of northwest China. Six antibiotics, seven heavy metals, ten mobile genetic elements (MGEs), and microbial community affected the ARGs profile in chicken dung and soil samples. Tetracycline antibiotic residues were prevalent in chicken manure, as were relatively high content of aureomycin during each culture period. Zinc (Zn) content was highest among the seven heavy metals in chicken feces. Chicken dung also enriched aminoglycosides, MLSB, and tetracycline ARGs, notably during brooding and high production. The farm had a minimal influence on antibiotics in the surrounding soil, but its effect on ARGs and MGEs closer to the farm (50 m) was stronger, and several ARGs and MGEs increased with distance. Manure microbial composition differed dramatically throughout breeding cycles and sampling distances. ARGs were more strongly related with antibiotics and heavy metals in manure than soil, whereas MGEs were the reverse. Antibiotics, heavy metals, MGEs, and bacteria in manure accounted 12.28%, 22.25%, 0.74%, and 0.19% of ARGs composition variance, respectively, according to RDA and VPA. Bacteria (2.89%) and MGEs (2.82%) only affected soil ARGs composition. These findings showed that heavy metals and antibiotics are the main factors affecting faecal ARGs and bacteria and MGEs soil ARGs. This paper includes antibiotic resistance data for large-scale laying hen husbandry in northwest China and a theoretical framework for decreasing antibiotic resistance. | 2023 | 37586197 |
| 7244 | 19 | 0.9919 | Manure and sulfadiazine synergistically increased bacterial antibiotic resistance in soil over at least two months. Manuring of arable soils may stimulate the spread of resistance genes by introduction of resistant populations and antibiotics. We investigated effects of pig manure and sulfadiazine (SDZ) on bacterial communities in soil microcosms. A silt loam and a loamy sand were mixed with manure containing SDZ (10 or 100 mg per kilogram of soil), and compared with untreated soil and manured soil without SDZ over a 2-month period. In both soils, manure and SDZ positively affected the quotients of total and SDZ-resistant culturable bacteria [most probable number (MPN)], and transfer frequencies of plasmids conferring SDZ resistance in filter matings of soil bacteria and an Escherichia coli recipient. Detection of sulfonamide resistance genes sul1, sul2 and sul3 in community DNA by polymerase chain reaction (PCR) and hybridization revealed a high prevalence of sul1 in manure and manured soils, while sul2 was mainly found in the loamy sand treated with manure and high SDZ amounts, and sul3 was not detected. By PCR quantification of sul1 and bacterial rrn genes, a transient effect of manure alone and a long-term effect of SDZ plus manure on absolute and relative sul1 abundance in soil was shown. The dynamics in soil of class 1 integrons, which are typically associated with sul1, was analysed by amplification of the gene cassette region. Integrons introduced by manure established in both soils. Soil type and SDZ affected the composition of integrons. The synergistic effects of manure and SDZ were still detectable after 2 months. The results suggest that manure from treated pigs enhances spread of antibiotic resistances in soil bacterial communities. | 2007 | 17298366 |