畜禽粪便中抗生素抗性基因(ARGs)污染问题及环境调控

抗生素在畜禽养殖业的大量使用造成抗生素抗性基因(ARGs)污染日益严重。动物体内诱导出的抗性菌株随粪便排出后,通过基因水平转移进入土壤进而污染土壤和地下水环境。堆肥作为一种将粪便资源化的优良传统方法,能否有效去除畜禽粪便中的ARGs而防止环境污染值得探讨。通过总结畜禽粪便ARGs污染现状,粪便堆肥过程中微生物群落结构变化与影响微生物变化的因素以及堆肥可能对粪便中ARGs造成的影响,提出将堆肥作为去除畜禽粪便中ARGs的一种有效手段,利用堆肥产生的高温去除抗性菌株和抗性质粒等,并且考虑加入能直接灭杀肠道微生物的化学抑制剂(如石灰氮、胺类、吲哚等),实现降低畜禽粪便ARGs丰度的可能。据此强调开展畜禽粪便中ARGs研究的必要性,认为将堆肥和ARGs研究结合起来,可以有效地降低这种新型污染物的污染水平。

Pollution and Environmental Regulation of Antibiotic Resistance Genes(ARGs) in Livestock Manure

There are increasing concerns about contamination of antibiotic resistance genes(ARGs) due to extensive uses of antibiotics in livestock and poultry breeding industries. After having induced in animal guts, antibiotic resistance bacteria are excreted via feces and then enter into soil environment through horizontal gene transfers, thus increasing the risk of ARGs propagation in soil and groundwater. It is unknown whether composting, a traditional method for utilization of animal wastes, could eliminate ARGs. This article summarized the current pollution situation of ARGs in livestock manure, and reviewed the changes of microbial community structure and their influencing factors and the dynamics of ARGs during composting. It is recommended that composting could be used as an effective way to reduce ARGs. During composting, high temperature could effectively kill antibiotic resistance bacteria and plasmids. Also chemical inhibitors such as lime nitrogen, amine and benzopyrrole could directly diminish enteric microorganisms, thus decreasing the abundance of ARGs. It is necessary to carry out a comprehensive research on ARGs removal through composting to mitigate the propagation of ARGs in the environment.