Antibiotic resistance genes (ARGs) in manure aerobic composting are a potential environmental pollutant. Therefore, reducing the abundance of ARGs is crucial. The effects of adding three-dimensional printed bulking agents (3DBAs) on ARGs in aerobic composting of swine manure were investigated in this study. Compared with the control group, 3DBAs with different addition dosages can greatest reduce the total ARGs by 5.98%, tetracycline resistance genes by 14.02%, macrolide resistance genes by 9.65%, and sulfonamide resistance genes by 20.59%. By further combining physicochemical parameters, host microorganisms, and mobile genetic elements (MGEs) for analysis, it was found that oxygen concentration was vital for ARGs reduction, and 3DBAs with regular porosity and uniform size indirectly regulate the activity of host microorganisms and MGEs abundance by changing the oxygen consumption, finally reducing vertical or horizontal ARGs transfer risks. Overall, 3DBAs addition is an effective strategy to reduce the abundance of ARGs in aerobic composting.

粪便好氧堆肥中的抗生素抗性基因（ARGs）是一种潜在的环境污染物。因此，减少 ARGs 的丰度至关重要。本研究研究了在猪粪好氧堆肥中添加三维打印填充剂 (3DBA) 对 ARGs 的影响。与对照组相比，不同添加剂量的3DBA可使总ARGs减少5.98%，四环素耐药基因减少14.02%，大环内酯耐药基因减少9.65%，磺胺耐药基因减少20.59%。通过进一步结合理化参数、宿主微生物和移动遗传元件 (MGEs) 进行分析，发现氧气浓度对于 ARGs 的减少至关重要，3DBA具有规则的孔隙率和均匀的尺寸，通过改变耗氧量间接调节宿主微生物的活性和MGEs的丰度，最终降低ARGs的垂直或水平转移风险。总体而言，添加 3DBA 是减少好氧堆肥中 ARGs 丰度的有效策略。