The Influence of Multi-generational High-Fiber Diet on the Gut Microbiota of Root Voles (microtus Oeconomus)

Fiber influences animal metabolism by affecting the gut microbiota, and high-fiber diets are often considered beneficial. However, existing research primarily focuses on the short-term effects of high-fiber diets, with limited studies on their long-term and trans-generational impacts on gut microbiota. This study investigated the long-term high-fiber diets and trans-generational effects on root voles (Microtus oeconomus)’ gut microbiota over five generations (F0 to F4) using 16S rRNA gene sequencing. Results showed that high-fiber diet significantly increased the diversity and complexity of gut microbiota and upregulated genes related to metabolism and immunity. The proportion of non-cellulose-degrading bacteria such as Proteobacteria and Spirochaetes decreased, while cellulose-degrading Firmicutes increased, raising the Firmicutes/Bacteroidetes ratio. Generational factors significantly influenced microbial community structure, reducing similarity. Over generations, both diets led to a reduction in beneficial bacteria such as Lactobacillus, Sporanaerobacter, and Clostridium, impairing the breakdown of proteins and starches. Meanwhile, potentially harmful bacteria like Desulfovibrio and Oscillospira increased, and the Firmicutes/Bacteroidetes ratio decreased, suggesting that a long-term, trans-generational uniform high-fiber diet may cause unfavorable shifts in gut microbiota. In summary, a high-fiber diet can increase gut microbiota abundance and diversity, promote cellulose-degrading bacteria, and upregulate certain metabolic genes, but long-term, uniform diets may cause gut microbiota imbalance, reducing beneficial bacteria and increasing potentially harmful ones.