紫色土丘陵区畜禽养殖场土壤中抗生素抗性基因分布特征

Characteristics of Antibiotic Resistance Genes in Various Livestock Feedlot Soils of the Hilly Purple Soil Region

鉴于紫色土高垦殖丘陵区土壤中抗生素抗性基因的潜在生态环境风险,本研究采用高通量荧光定量PCR技术,分析了抗生素抗性基因在不同类型畜禽养殖场(养猪场、养鸡场和养牛场)土壤中的丰度和多样性.结果表明,3种养殖场土壤中共检出79种抗生素抗性基因和5种可移动基因元件,其中多重耐药类基因是养殖场土壤中丰度最高的耐药基因.不同养殖场土壤中抗生素抗性基因的丰度和多样性均表现为养鸡场和养猪场样品高于养牛场土壤,且3种养殖场土壤样品中的抗性基因表现出不同的类别分布特征.养殖场土壤中较高的可移动基因元件丰度,及其与抗生素抗性基因丰度显著的相关性(P<0.05)说明,可移动基因元件可能促进了抗生素抗性基因在养殖场土壤中的迁移和扩散.

Given the potential risk posed by antibiotic resistance genes( ARGs) to the eco-environment in the hilly purple soil region,which has been intensively utilized by human,surface soil samples were collected from feedlots of pig,chicken,and cattle farms and were analyzed for the diversity and abundance of ARGs using high-throughput QPCR. In total,79 ARGs and 5 mobile genetic elements( MGEs) were detected across all samples. Among these genes,multidrug resistance genes were the most abundant type of ARGs.More abundant and diverse ARGs were observed in feedlot soil samples from pig and chicken farms than those from cattle feedlot soils,and these samples showed different distribution patterns of ARGs. High abundance of MGEs and their significant correlation with ARGs( P < 0. 05) implied an important role of MGEs in the dissemination of ARGs in livestock feedlot soils.