Abstract：
The high load of agrochemicals and antibiotics present in agricultural aquatic environments represents a risk for wildlife. Since enteric bacteria, which play a key role in the physiological functioning of their hosts, are sensitive to a wide variety of pollutants, their study allows to evaluate the health of organisms. This study aimed to evaluate the effects of commercial formulations of a glyphosate-based herbicide (GBH) and the antibiotic ciprofloxacin (CIP), individually and in mixture, on the bacterial diversity of the intestinal content of common toad (Rhinella arenarum) tadpoles. The diversity of cultivable fast-growing bacteria with low nutritional requirements was evaluated using classic microbiological tests and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry identification. Bacterial diversity varied among treatments. Taxa diversity increased in the GBH-treated group but decreased in the CIP-treated group. Remarkably, Yersinia spp. and Proteus spp. were only found in the GBH-treated group. The prevalence of Klebsiella spp. and Pseudomonas spp. decreased in the intestinal microbiota of the GBH-CIP-treated group. To our knowledge, this is the first report on the alteration of cultivable enteric bacteria of autochthonous tadpoles due to two pollutants of emerging concern. Our results demonstrate that R. arenarum tadpoles can be used as non-conventional model organisms for environmental pollution monitoring. Our preliminary findings would contribute to understanding how the presence of GBH and CIP in freshwaters may represent a threat to wildlife and human health by causing enteric dysbiosis of part of the bacterial community.
摘要：
农业水生环境中存在的农用化学品和抗生素的高负荷对野生动植物构成了风险。由于肠道细菌，它们在宿主的生理功能中起着关键作用，对各种各样的污染物敏感，他们的研究允许评估生物体的健康。本研究旨在评估草甘膦除草剂（GBH）和抗生素环丙沙星（CIP）的商业配方的影响，单独和混合，关于普通蟾蜍（Rhinellaarenarum）t肠道内容物的细菌多样性。使用经典的微生物测试和基质辅助激光解吸电离飞行时间（MALDI-TOF）质谱鉴定，评估了营养需求低的可培养快速生长细菌的多样性。细菌多样性因处理而异。GBH处理组的分类群多样性增加，而CIP处理组的分类群多样性减少。值得注意的是,耶尔森氏菌。和Proteusspp.仅在GBH治疗组中发现。克雷伯菌属的患病率。和假单胞菌属。GBH-CIP处理组的肠道微生物群减少。据我们所知,这是有关由于两种新出现的污染物而引起的本地t的可培养肠细菌变化的第一份报告。我们的结果表明R.arenarumt可以用作非常规模型生物进行环境污染监测。我们的初步发现将有助于了解淡水中GBH和CIP的存在如何通过引起部分细菌群落的肠道菌群失调来威胁野生动植物和人类健康。
