Abstract
Antibiotic-resistant bacteria and genes are recognized as new environmental pollutants that warrant special concern. There were few reports on veterinary antibiotic-resistant bacteria and genes in China. This work systematically analyzed the prevalence and distribution of sulfonamide resistance genes in soils from the environments around poultry and livestock farms in Jiangsu Province, Southeastern China. The results showed that the animal manure application made the spread and abundance of antibiotic resistance genes (ARGs) increasingly in the soil. The frequency of sulfonamide resistance genes was sul1 > sul2 > sul3 in pig-manured soil DNA and sul2 > sul1 > sul3 in chicken-manured soil DNA. Further analysis suggested that the frequency distribution of the sul genes in the genomic DNA and plasmids of the SR isolates from manured soil was sul2 > sul1 > sul3 overall (p<0.05). The combination of sul1 and sul2 was the most frequent, and the co-existence of sul1 and sul3 was not found either in the genomic DNA or plasmids. The sample type, animal type and sampling time can influence the prevalence and distribution pattern of sulfonamide resistance genes. The present study also indicated that Bacillus, Pseudomonas and Shigella were the most prevalent sul-positive genera in the soil, suggesting a potential human health risk. The above results could be important in the evaluation of antibiotic-resistant bacteria and genes from manure as sources of agricultural soil pollution; the results also demonstrate the necessity and urgency of the regulation and supervision of veterinary antibiotics in China.
Highlights
In the past few decades, veterinary antibiotics have been widely used in many countries to treat disease and promote animal growth
The present study could be important in the evaluation of the pollution of soils used for agriculture by antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) from manure; this study demonstrates the necessity and urgency for the regulation and supervision of veterinary antibiotics in China
Enumeration of the total culturable microbial populations and SR Bacteria in the soil The number of total culturable microbial populations on the nutrient agar ranged from 1.966107 to 9.756107 colony-forming units (CFUs)/g soil and that of the SR isolates on the nutrient agar ranged from 4.56105 to 9.06107 CFU/g soil (Figure 1), which were higher than those of the reported aquaculture-agriculture ponds (3.06104 to 1.66106 and 3.06102 to 4.16104, respectively) [19]
Summary
In the past few decades, veterinary antibiotics have been widely used in many countries to treat disease and promote animal growth. This release together with antibiotic-resistant bacteria (ARB) is a great concern recently [1], primarily because the land application of antibiotic-polluted manure in agricultural practice introduced bacteria carrying antibiotic resistance genes (ARGs) into the soil and had a significant effect on the ARB promotion and selection. Evidence from the last 35 years demonstrates that there was consistent correlation between the use of antibiotic-contaminated manure on farms and the transfer of ARGs in human pathogens, as well as the direct shift of ARB from animals to humans [4]. ARGs are recognized as new environmental pollutants, and special concern is warranted due to their potential environmental and human health risks
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
