Ceftiofur in swine manure contributes to reducing pathogens and antibiotic resistance genes during composting

• Published in: Environmental research 2024-07, Vol.252, p.119033-119033, Article 119033
• Main Authors: Ma, Wenjin, An, Boyu, Xu, Xiangyue, Huo, Meixia, Mi, Kun, Tian, Xiaoyuan, Kou, Ziyan, Tang, Aoran, Cheng, Guyue, Huang, Lingli
• Format: Article
• Language: English
• Subjects: Antibiotic resistance genes; Cephalosporins; Potential host bacteria; Removal efficiency
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2024.119033

Aerobic composting is a common way for the disposal of feces produced in animal husbandry, and can reduce the release of antibiotic resistance genes (ARGs) from feces into the environment. In this study, we collected samples from two distinct treatments of swine manure compost with and without ceftiofur (CEF), and identified the ARGs, mobile genetic elements (MGEs), and bacterial community by metagenomic sequencing. The impacts of CEF on the bacterial community composition and fate of ARGs and MGEs were investigated. With increasing composting temperature and pH, the concentration of CEF in the manure decreased rapidly, with a degradation half-life of 1.12 d and a 100% removal rate after 10 d of aerobic composting. Metagenomics demonstrated that CEF in the manure might inhibit the growth of Firmicutes and Proteobacteria, thereby reducing some ARGs and MGEs hosted by these two bacteria, which was further confirmed by the variations of ARGs and MGEs. A further redundancy analysis suggested that pH and temperature are key environmental factors affecting ARG removal during composting, and intI1 and bacterial communities also have significant influence on ARG abundance. These results are of great significance for promoting the removal of some ARGs from animal manure by controlling some key environmental factors and the type of antibiotics used in animals. •Aerobic composting can lower the environmental risk of ceftiofur (CEF).•The removal rate of CEF reached 100% after 10 days of aerobic composting.•The CEF in manure might inhibit the growth of Firmicutes and Proteobacteria.•The CEF in manure contribute to reduce pathogens and ARGs during composting.•Controlling temperature and pH can increase the removal of ARGs and CEF.