Microbial Community Characteristics And Antibiotic Resistance Genes In Duck-fish Farms Environment

Due to water resources, the farming mode of "duck in polyculture with fish" is given priority to in Guangdong province and even the whole south China region. In the breeding process, a large number of antibiotics are used to promote animal growth and preventive treatment of disease, result in the antibiotic resistance of animal pathogenic bacteria has aroused more and more serious. These bacteria carrying resistance genes through excreta into the environment of soil, surface and underground water, as a major source of antibiotic resistance genes in the environment. The antibiotic resistance gene has been widespread concern as a potential environmental pollutants.In this study, surrounding environment sample(soil, sediment and water) of three farms of duck polycultured with fish were collected four times every three months randomly to investigate antibiotic resistance and microbial community structure. Results showed that relative abundance of the sulfonamides resistance genes was highest in all samples, and sul1 gene was the highest by all ARGs. The sul1 gene average relative abundance of soil, sediment and water samples, respectively, 8.15×10-1, 3.12×10-1 and 2.31×10-1 copies / 16 S r DNA copies. Combined with the abundance of each gene, and the correlation analysis of various types of genes found an indicator gene in each type of resistance genes, the sulfonamide resistance genes was sul1, the tetracyclines resistance genes was tet M, the quinolones resistance genes was aac(6')-Ib, the amidealcohols resistance genes was flo R, the ?-lactam resistance genes was blaTEM. In different environment samples, microbial concentration was soil>sediment>water(p<0.05), the relative abundance of all ARGs was soil samples significantly higher than sediment and water samples. In different seasons samples, the microbial concentration and the relative abundance of all ARGs had weaken different, but which did not change with the seasons by a significantly variation, needing more research to find variation.Understanding the microbial structure and diversity in environment of duck-fish farms, different samples in different seasons, the microbial structure and diversity were different. Proteobacteria, Bacteroidetes, Actinobacteria, Firmicutes and Chloroflexi were advantage bacterials in all samples and Acinetobacter, Pseudomonas and Flavobacterium were advantage bacterials of pathogenicity, which were different proportion in different samples and seasons. Study about the correlation between pathogens and antibiotic resistance genes, Flavobacterium, Corynebacterium and Pseudomonas had strong correlation of ARGs. Between the concentration of ARGs and pathogenic bacteria had a relationship in environment. This provide a reference to protect disease in different seasons.