Copper (Cu) is one of the environmental contaminations which can pose significant risks for organisms. The current study explores the effects of Cu exposure on the growth, intestinal histology and microbial ecology in Bufo gargarizans. The results revealed that 0.5–1 μM Cu exposure induced growth retardation (including reduction of total body length and wet weight) and intestinal histological injury (including disordered enterocyte, changes in the villi and vacuoles) of tadpoles. Also, high-throughput sequencing analysis showed that Cu exposure caused changes in richness, diversity and structure of intestinal microbiota. Moreover, the composition of intestinal microbiota was altered in tadpoles exposed to different concentrations of Cu. At the phylum level, we observed the abundance of proteobacteria was increased, while the abundance of fusobacteria was decreased in the intestinal microbiota of tadpoles exposed to 1 μM Cu. At the genus level, a reduced abundance of kluyvera and aeromonas was observed in the intestinal microbiota of tadpoles under the exposure of 0–0.5 μM Cu. Finally, functional predictions revealed that tadpoles exposed to copper may be at a higher risk of developing metabolic disorders or diseases. Above all, our results will develop a comprehensive view of the Cu exposure in amphibians and will yield a new consideration for sublethal effects of Cu on aquatic organisms.

铜（Cu）是一种环境污染物，可能对生物造成重大风险。当前的研究探讨了铜暴露对中华蟾蜍生长，肠道组织学和微生物生态学的影响。结果表明，暴露于0.5–1μM的铜会引起growth的生长迟缓（包括减少全身长和湿重）和肠道组织学损伤（包括肠上皮细胞紊乱，绒毛和液泡变化）。此外，高通量测序分析表明，铜暴露导致肠道菌群的丰富性，多样性和结构发生变化。此外，暴露于不同浓度的铜的。中肠道菌群的组成发生了变化。在门的水平，我们观察到丰富的在暴露于1μMCu的t的肠道菌群中，增加了变形杆菌的数量，而减少了富集细菌的含量。在属水平，的丰度降低克吕沃尔和气单胞菌在蝌蚪0-0.5μMCu的曝光下的肠道微生物群中观察到。最后，功能预测表明，暴露于铜的may可能处于代谢紊乱或疾病的更高风险中。最重要的是，我们的结果将全面了解两栖动物中的铜暴露情况，并将重新考虑铜对水生生物的亚致死作用。