IRSTEA, 17 Avenue de Cucillé, 35044 Rennes, France; Université Européenne de Bretagne, France.
Université d'Angers, LETG-Angers LEESA UMR CNRS 6554, UFR Sciences, 2 Boulevard Lavoisier, 49045 Angers, France.
Sci Total Environ. 2014 Jun 1;482-483:269-75. doi: 10.1016/j.scitotenv.2014.02.136. Epub 2014 Mar 20.
A field plot experiment was carried out to evaluate the impact of spreading chicken manure containing enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP), on the levels of CIP-resistant Enterobacteriaceae in soil. The manures from chickens treated with ENR and from untreated control chickens were applied on six plots. Total and CIP-resistant Enterobacteriaceae were counted on Violet Red Bile Glucose medium containing 0 to 16mg L(-1) of CIP. A total of 145 isolates were genotyped by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The minimum inhibitory concentration (MIC) of CIP for the isolates of each ERIC-PCR profile was determined. The most frequently isolated Enterobacteriaceae included Escherichia coli, and to a lesser extent, Enterobacter and 5 other genera from environmental origin. The composition of the E. coli community differed between manure and manured soil suggesting that the E. coli genotypes determined by ERIC-PCR varied significantly in their ability to survive in soil. One of these genotypes, including both susceptible and resistant isolates, was detected up to 89 days after the manure was applied. Most of the E. coli isolated in soil amended with manure from treated chickens was resistant to CIP (with a MIC ranging between 2 and 32mg L(-1)). In contrast, despite the presence of ENR in soil at concentrations ranging from 13-518μg kg(-1), the environmental Enterobacteriaceae isolates had a CIP MIC≤0.064mg L(-1), except one isolate which had a MIC of 0.25mg L(-1), These results showed that spreading manure from ENR-treated chickens enabled CIP-resistant E. coli to persist for at least three months in the soil. However, neither the presence of fluoroquinolones, nor the persistence of CIP-resistant E. coli, increased the CIP-susceptibility of environmental Enterobacteriaceae.
一项田间试验评估了在土壤中传播含有恩诺沙星（ENR）和其代谢物环丙沙星（CIP）的鸡粪对 CIP 耐药肠杆菌科水平的影响。用 ENR 处理过的鸡的粪便和未处理的对照鸡的粪便分别施用到 6 个地块。在含有 0 至 16mg L(-1) CIP 的 Violet Red Bile Glucose 培养基上计数总肠杆菌科和 CIP 耐药肠杆菌科。对 145 株分离株进行肠杆菌属重复基因间一致性聚合酶链反应（ERIC-PCR）基因分型。根据 ERIC-PCR 图谱确定每种分离株的环丙沙星最小抑菌浓度（MIC）。最常分离的肠杆菌科包括大肠杆菌，其次是肠杆菌和其他 5 个来自环境的属。粪便和施肥土壤中的大肠杆菌群落组成不同，表明 ERIC-PCR 确定的大肠杆菌基因型在其在土壤中生存的能力方面存在显著差异。其中一种基因型，包括敏感和耐药分离株，在粪便施用到土壤后 89 天仍被检测到。用来自处理过的鸡的粪便施肥的土壤中分离的大多数大肠杆菌对 CIP 耐药（MIC 范围在 2 至 32mg L(-1)之间）。相比之下，尽管土壤中存在浓度范围在 13-518μg kg(-1)之间的恩诺沙星，但环境肠杆菌科分离株的 CIP MIC≤0.064mg L(-1)，除了一株 MIC 为 0.25mg L(-1)的分离株。这些结果表明，传播来自 ENR 处理过的鸡的粪便至少使土壤中的 CIP 耐药大肠杆菌在 3 个月内持续存在。然而，氟喹诺酮类药物的存在或 CIP 耐药大肠杆菌的持续存在，均未增加环境肠杆菌科对 CIP 的敏感性。
