摘要
      蚯蚓转化是一种环保的生物过程，可以将牲畜粪便转化为营养丰富的良性有机肥料。然而，人们对蚯蚓转化的牲畜粪便对蚯蚓肠道微生物群中抗生素耐药性的影响知之甚少。在此，进行了实验室规模的蚯蚓堆肥，通过宏基因组分析全面评估了以牛粪为食的蚯蚓肠道中抗生素抗性基因（ARGs）的转移。还评价了铜（Cu）作为一种食品添加剂的作用。CM显著富集了前肠和中肠的抗生素抗性组，而在后肠则减少了。对于金属抗性基因（MRG）也观察到了类似的趋势。值得注意的是，CM中的Cu对蚯蚓肠道中ARGs和MRGs的组成几乎没有影响。CM改变的蚯蚓肠道微生物组是ARG和MRG变化的原因。在虫粪中，Cu（100和300mg/kg）显著增加了ARGs和MRGs的丰度。我们的研究为蚯蚓肠道中ARGs和MRGs对CM的反应提供了有价值的见解，并强调了在畜禽养殖中明智使用重金属作为饲料添加剂的必要性。
Abstract
Earthworm conversion is an eco-friendly biological process that converts livestock waste into a benign nutrient-rich organic fertilizer. However, little is known about the impacts of earthworm-converted livestock manure on the antibiotic resistome in the earthworm gut microbiota. Herein, lab-scale vermicomposting was performed to comprehensively evaluate the shift of antibiotic resistance genes (ARGs) in the earthworm gut—feeding on cow manure (CM)—by metagenomic analysis. The effects of copper (Cu) as a food addictive were also evaluated. CM substantially enriched the antibiotic resistome in the foregut and midgut, while it decreased in the hindgut. A similar trend was observed for metal resistance genes (MRGs). Notably, Cu in the CM had little effect on composition of ARGs and MRGs in earthworm gut. The earthworm gut microbiome altered by CM was responsible for the shift of ARGs and MRGs. In wormcast, Cu (100 and 300 mg/kg) significantly increased the abundance of ARGs and MRGs. Our study provides valuable insight into the response of ARGs and MRGs to CM in earthworm gut, and underscores the need for the judicious use of heavy metals as feed additives in livestock and poultry farming.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722061095