Rice- or pork-based diets with similar calorie and content result in different rat gut microbiota

Rice is the most important food crop, and pork is the most widely eaten meat in the world. In this study, we compared the gut microbiota of the rats fed with rice or pork mixed diets, which have similar caloric contents. The physiological indices (body weights, hematology, serum chemistry, organ weights and histopathology) of two groups were all within the normal range. Two diets did not induce difference in the diversity of gut bacteria. However, Firmicutes were significantly higher in rice diet group, while Bacteroidetes were enriched in pork diet group. Butyrate and the bacteria enzymes β-glucuronidase, β-glucosidase and nitroreductase in the feces were all drastically higher in pork diet group. This study indicates that different diets with similar calorie and nutritional composition could change the community structure but not the diversity of rat fecal microbiota.

水稻是全球最重要的粮食作物，猪肉则是全球食用范围最广的肉类。本研究针对热量含量相近的水稻日粮与猪肉日粮，对比饲喂两种日粮的大鼠的肠道菌群（gut microbiota）。两组大鼠的各项生理指标，包括体重、血液学指标、血清生化指标、脏器重量及组织病理学检查结果，均处于正常参考范围内。两种日粮未对肠道细菌的多样性产生显著影响。然而，水稻日粮组的厚壁菌门（Firmicutes）丰度显著更高，而猪肉日粮组则富集了拟杆菌门（Bacteroidetes）。猪肉日粮组的粪便中丁酸（butyrate）含量以及细菌酶类β-葡萄糖醛酸苷酶（β-glucuronidase）、β-葡萄糖苷酶（β-glucosidase）与硝基还原酶（nitroreductase）的活性均显著升高。本研究表明，热量与营养组成相近的不同日粮，可改变大鼠粪便菌群的群落结构，但不会影响其多样性。