Environmental Cadmium Exposure Perturbs Gut Microbial Dysbiosis in Ducks

SIMPLE SUMMARY: Cadmium is a prevalent heavy metal known to contribute to environmental contamination. Moreover, cadmium in the environment may accumulate in animals and plants and then enter the human body through the food chain, seriously threatening food safety and public health. Currently, cadmium exposure has been demonstrated to cause liver and kidney damage, as well as abnormal bone development, in ducks. However, there is limited research on the impact of cadmium on the gut microbiota of ducks. In this study, we investigated the alterations in the gut microbiota of ducks exposed to cadmium and identified the detrimental effects of cadmium on the gut microbiota. ABSTRACT: Ore extraction, chemical production, and agricultural fertilizers may release significant amounts of heavy metals, which may eventually accumulate widely in the environment and organisms over time, causing global ecological and health problems. As a recognized environmental contaminant, cadmium has been demonstrated to cause osteoporosis and renal injury, but research regarding the effects of cadmium on gut microbiota in ducks remains scarce. Herein, we aimed to characterize the adverse effects of cadmium on gut microbiota in ducks. Results indicated that cadmium exposure dramatically decreased gut microbial alpha diversity and caused significant changes in the main component of gut microbiota. Moreover, we also observed significant changes in the gut microbial composition in ducks exposed to cadmium. A microbial taxonomic investigation showed that Firmicutes, Bacteroidota, and Proteobacteria were the most preponderant phyla in ducks regardless of treatment, but the compositions and abundances of dominant genera were different. Meanwhile, a Metastats analysis indicated that cadmium exposure also caused a distinct increase in the levels of 1 phylum and 22 genera, as well as a significant reduction in the levels of 1 phylum and 36 genera. In summary, this investigation demonstrated that cadmium exposure could disturb gut microbial homeostasis by decreasing microbial diversity and altering microbial composition. Additionally, under the background of the rising environmental pollution caused by heavy metals, this investigation provides a crucial message for the assessment of environmental risks associated with cadmium exposure.