| Abstrakt: |
To find out the variations of antibiotic resistance genes during livestock manure anaerobic digestion at different temperatures, dairy manure was used to investigate the characteristics of anaerobic digestion at 45°C and 65°C and the effect of temperature, SCOD, NH4+/-N and intI1 on the varying abundances of tetracycline resistance genes (tetG, tetT, tetO, tetC, tetX and tetW). Compared with that at 45°C, it was found higher biogas production rate occurred in the early stage of anaerobic digestion at 65°C, but total biogas production and methane production has not significant difference. Similar trends of 4+/-N, SCOD, TOC and pH were shown at 45°C and 65°C. The total copies of target genes at 45°C increased by 0.27 logs, among of which the absolute abundances of tetW and tetG genes increased by 0.29 logs and 0.03 logs, respectively. However the absolute abundances of tetT, tetO, tetC and tetX genes decreased by 1.67, 0.15, 0.08 and 0.84 logs, respectively. The total copies of target genes at 65 t decreased by 1.22 logs, and the abundances of each target gene decreased over 40%. Redundancy analysis showed that most of the tetracycline resistance genes were negatively correlated with 4+/-N and temperature, and the higher the digestion temperature, the better the removal of antibiotic resistance genes. [ABSTRACT FROM AUTHOR] |
