4种粪便堆肥过程中抗生素的降解特性

饲料中抗生素的广泛使用导致了粪便中抗生素的大量残留,堆肥工艺可以降解残留的抗生素.本研究以蛆粪、鸡粪、猪粪和牛粪为对象,利用中试好氧堆肥装置,研究不同类型粪便的抗生素残留情况及其堆肥降解特性.结果表明,磺胺类、氟喹诺酮类、四环素类和大环内酯类是主要存在的抗生素类型,不同类型粪便其优势抗生素均不同.对各粪便堆肥中抗生素降解规律研究发现:氟喹诺酮类抗生素和土霉素在堆肥第7 d检出水平为0,降解速度最快;强力霉素在4种粪便堆肥中的降解幅度在85%以上;磺胺类抗生素在鸡粪、猪粪和牛粪堆肥中的降解幅度在80%以上,但是在蛆粪堆肥中的降解效果较差;大环内酯类抗生素仅存在蛆粪中,经堆肥其降解幅度为70. 79%.相关性结果显示,含水率和容重是影响4种粪便堆肥抗生素降解率最主要的环境因子.

Degradation Characteristics of Antibiotics During Composting of Four Types of Feces

The widespread use of antibiotics in feed results in a large number of antibiotic residues in feces. Composting technology can degrade these residual antibiotics. A pilot-scale aerobic composting device was used to analyze the antibiotic residues and composting degradation characteristics of four types of feces (maggot manure, chicken manure, pig manure, and cow manure). Results showed that sulfonamides (SAs), fluoroquinolones (FQs), tetracycline (TCs), and macrolides (MAs) were the main antibiotics, and different type of feces had different dominant antibiotics. The contents of FQs and oxytetracycline (OTC) were none on the seventh day of the compost, and their degradation rates were the fastest. After composting, the degradation rate of doxycycline (DOX) in the four types of fecal composts was more than 85%. Meanwhile, the degradation rates of SAs in chicken, pig, and cow manure composts were also more than 80%, which was much lower in the one in maggot manure compost. MAs were only found in maggot manure, and the degradation rate was 70.79% after composting. Correlation analysis indicated that the water content and bulk density were the most important environmental factors affecting the degradation rates of antibiotics in the four types of fecal composts.