Impacts of florfenicol on soil bacterial community structure and diversity by high throughput sequencing analysis

To investigate the impact of florfenicol on soil microbial community structure and diversity, an indoor florfenicol exposure model was established. Soil samples were collected at different concentrations of florfenicol (0, 0.05, 0.5, 5, and 50 mg/kg) on days 0, 7, 30, and 60. High-throughput sequencing was employed to examine the changes in soil microbial community structure, diversity, and abundance. The analysis revealed a total of 31874 operational taxonomic units (OTUs) in the soil samples, averaging 9524 OTUs per sample. The number of soil microbial community OTUs declined with increasing florfenicol concentration. The microbial species richness and diversity showed a decreasing trend at day 7, while the treatment group with 50 mg/kg florfenicol at 60 days exhibited the lowest richness index. Examination of the soil microbial community structure identified 50 phyla and 1303 genera. At the phylum level, the abundance of Actinobacteria and Bacteroides decreased with increasing florfenicol concentration. Similarly, at the genus level, some of the dominant genera displayed a decline in abundance with the rise of florfenicol concentration. Cluster analysis demonstrated significant temporal and concentration variability. The results indicate differences in the composition, diversity, dominance, abundance, and evenness of soil bacterial communities among different groups. Florfenicol has a significant negative impact on the structure and diversity of soil microbial communities. The findings of this study provide a scientific basis for the rational use of florfenicol in livestock farming to maintain a healthy and stable soil microecological environment.