CESAM & Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
University of Coimbra, CESAM & Department of Life Sciences, Faculty of Science and Technology, Calçada Martins de Freitas, 3000-456 Coimbra, Portugal.
Int J Environ Res Public Health. 2021 Mar 20;18(6):3218. doi: 10.3390/ijerph18063218.
The emergence of antibiotic-resistant pathogens due to worldwide antibiotic use is raising concern in several settings, including aquaculture. In this work, the selection of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) was evaluated after exposure of zebrafish to oxytetracycline (OTC) for two months, followed by a recovery period. The selection of ARB in water and fish was determined using selective media. The abundance of genes was estimated through qPCR. Higher prevalence of ARB was measured in all samples exposed to the antibiotic when compared to control samples, although statistical significance was only achieved five days after exposure. Isolates recovered from samples exposed to the antibiotic were affiliated with and . Various antibiotic susceptibility profiles were detected and 37% of the isolates displayed multidrug resistance (MDR). The selection of the gene was confirmed by qPCR at the highest OTC concentration tested. Two MDR isolates, tested using zebrafish embryos, caused significant mortality, indicating a potential impact on fish health and survival. Overall, our work highlights the potential impact of antibiotic contamination in the selection of potential pathogenic ARB and ARGS.
由于全球范围内抗生素的使用，抗生素耐药病原体的出现引起了人们的关注，包括水产养殖领域。在这项工作中，我们评估了斑马鱼在接触土霉素（OTC）两个月后，经过恢复期，其体内和水中的抗生素耐药细菌（ARB）和抗生素耐药基因（ARGs）的选择情况。通过选择性培养基来确定水中和鱼体内 ARB 的选择情况。通过 qPCR 来估计 基因的丰度。与对照样本相比，所有暴露于抗生素的样本中均检测到更高的 ARB 流行率，尽管仅在暴露后 5 天达到了统计学意义。从暴露于抗生素的样本中回收的分离株与 和 有关。检测到各种抗生素药敏谱，其中 37%的分离株表现出多药耐药性（MDR）。通过 qPCR 在测试的最高 OTC 浓度下证实了 基因的选择。使用斑马鱼胚胎测试的两个 MDR 分离株导致了显著的死亡率，这表明它们可能对鱼类健康和生存造成潜在影响。总的来说，我们的工作强调了抗生素污染对潜在致病 ARB 和 ARGS 选择的潜在影响。
