摘要

这项研究的目的是评估在现场条件下，安普霉素给药对从鸡粪和家蝇中分离的大肠杆菌（大肠杆菌）菌株中抗生素抗性发展的影响。给药组（n = 25,000）中的鸡在第1至5天的饮用水中连续给予安普霉素预防剂量（0.5mg / l），而未加药的饮水组中未添加抗生素（n = 25,000 ）。超过40天，从同一养鸡场的加药和未加药的鸡和家蝇粪便样品中分离出总计1170个大肠杆菌菌株。当与第0天（8μg/ ml）相比时，从加药组获得的大肠杆菌菌株的安普霉素MIC90值从第2天到第6天（256-1024μg/ ml）增加32-128倍。从未加药的鸡和家蝇中分离的菌株在第一周期间始终具有低MIC90值（8-16μg/ ml），但从第8天到第10天（128-1024μg/ ml）显示出急剧增加。在来自加药（n = 71），未加药（n = 32）和家蝇组（n = 42）的大肠杆菌菌株中检测到阿泊拉霉素抗性基因aac（3）-IV。 aac（3）-IV阳性的所有菌株分为12个脉冲场凝胶电泳（PFGE）类型。 PFGE类型A，E和G是药物组和家蝇组中的主要类型，表明家蝇在传播大肠杆菌抗性菌株中起重要作用。总之，我们的研究表明，安普霉素给药可以促进阿泊拉霉素抗性大肠杆菌和阿泊拉霉素抗性基因acc（3）-IV的发生。反过来，这些菌株可能由家蝇传播，因此增加了向公众传播耐多药的大肠杆菌的潜在风险。

The aim of this study was to evaluate the influence of apramycin administration on the development of antibiotic resistance inEscherichia coli (E. coli) strains isolated from chicken feces and houseflies under field conditions. Chickens in the medicated group (n = 25,000) were given successive prophylactic doses (0.5 mg/l) of apramycin in their drinking water from Days 1 to 5, while no antibiotics were added to the un-medicated groups drinking water (n = 25,000). Over 40 days, a total of 1170 E. colistrains were isolated from fecal samples obtained from medicated and un-medicated chickens and houseflies from the same chicken farm. Apramycin MIC90 values for E. coli strains obtained from the medicated group increased 32-128 times from Days 2 to 6 (256-1024 μg/ml) when compared to those on Day 0 (8 μg/ml). Strains isolated from un-medicated chickens and houseflies had consistently low MIC90 values (8-16 μg/ml) during the first week, but showed a dramatic increase from Days 8 to 10 (128-1024 μg/ml). The apramycin resistance gene aac(3)-IV was detected in E. coli strains from medicated (n = 71), un-medicated (n = 32), and housefly groups (n = 42). All strains positive for aac(3)-IV were classified into 12 pulsed-field gel electrophoresis (PFGE) types. PFGE types A, E, and G were the predominant types in both the medicated and housefly groups, suggesting houseflies play an important role in spreading E. coli-resistant strains. Taken together, our study revealed that apramycin administration could facilitate the occurrence of apramycin-resistant E. coli and the apramycin resistance gene acc(3)-IV. In turn, these strains could be transmitted by houseflies, thus increasing the potential risk of spreading multi-drug-resistant E. coli to the public.

https://www.ncbi.nlm.nih.gov/pubmed/29535694