【摘要】 畜禽粪便是抗生素抗性基因(antibiotic resistant genes,ARGs)进入环境的重要途径,为了削减畜禽粪便中的ARGs,在为期46 d的鸡粪与中药渣共堆肥后,对不同阶段ARGs和可移动基因元件(mobile gene elements,MGEs)的丰度通过实时定量PCR进行检测. 100种ARGs中检测到21种,以及2种整合酶基因(int I1和int I2)和3种转座酶基因(tnp A-01、tnp A-02和tnp A-03).结果表明,在堆肥过程中5种MGEs均显著降低,其中tnp A-01和tnp A-02去除效果最好,减少了两个数量级;氨基糖苷类抗性基因aac A/aph D和aad E显著性降低(P <0. 05);β-内酰胺类抗性基因bla OXA1与堆肥天数显著相关(P=0. 016),其去除率为78. 63%;林可酰胺类抗性基因均随堆肥时间显著降低,平均去除率为90. 39%;四环素类抗性基因的去除效果相差较大,tet G降低了99. 77%,tetR仅降低了31. 72%;喹诺酮类抗性基因qnr D去除率最高为99. 89%;磺胺类中sulⅢ的去除率高达99. 88%,而sulⅠ呈增长趋势. ARGs与MGEs相关性表明tnp A-01与ARGs之间具有显著相关性(P <0. 05). ARGs随堆肥时间的变化趋势表明,中药渣与鸡粪共堆肥可显著降低ARGs丰度,从而降低畜禽粪便在农田施用中ARGs扩散的风险.更多还原

【Abstract】 Livestock manure is an important pathway by which antibiotic resistance genes( ARGs) enter the environment. To reduce the occurrence of antibiotic resistance genes in manures,we studied the variations of ARGs and mobile gene elements( MGEs) during the 46-day co-composting of chicken manure with Chinese medicinal herbal residues. The abundance of 100 ARGs and 5 MGEs were measured by Real-Time Quantitative PCR with 0,3,7,14,28,and 46 d co-composting. We detected 21 ARGs,2 integrase genes( int I1 and int I2),and 3 transposase genes( tnp A-01,tnp A-02,and tnp A-03). The abundance of 5 MGEs significantly declined with co-composting time,particularly tnp A-01 and tnp A-02,which were reduced by two orders of magnitude. The abundance of aac A/aph D and aad E were significantly reduced( P < 0. 05) in aminoglycoside resistance genes. In β-lactam resistance genes,the strongest relationships were demonstrated between bla OXA1 and compost days( P = 0. 016),and the removal rate was 78. 63%. The average removal rate was 90. 39% for amide resistance genes,which decreased significantly with composting time. The removal ratios were different among tetracycline resistance genes. For example,the removal ratios of tet G and tetR were 99. 77% and 31. 72%,respectively. The highest removal rate of qnr D was 99. 89%. The removal rate of sulⅢ was as high as 99. 88%,while sulⅠ showed an increasing trend. Correlations between ARGs and MGEs were significant correlation for tnp A-01 and ARGs( P < 0. 05). The trend of ARGs with composting time indicates that the composting of Chinese medicine residues and chicken manure can significantly reduce the abundance of ARGs,thus reducing the risk of ARGs being distributed via livestock manure application.更多还原