Comparative analysis of the gut microbiota of mice fed a diet supplemented with raw and cooked beef loin powder

We used 16S ribosomal RNA sequencing to evaluate changes in the gut microbiota of mice fed a diet supplemented with either raw or cooked beef loin powder for 9 weeks. Male BALB/c mice (n = 60) were randomly allocated to five groups: mice fed AIN-93G chow (CON), chow containing 5% (5RB) and 10% (10RB) raw beef loin powder, and chow containing 5% (5CB) and 10% (10CB) cooked beef loin powder. Dietary supplementation with both RB and CB increased the relative abundance of Clostridiales compared to the CON diet (p < 0.05). Mice fed 10RB showed a significantly higher relative abundance of Firmicutes (p = 0.018) and Lactobacillus (p = 0.001) than CON mice, and the ratio of Firmicutes/Bacteroidetes showed an increasing trend in the 10RB mice (p > 0.05). Mice fed 10CB showed a higher abundance of Peptostreptococcaceae and a lower abundance of Desulfovibrionaceae compared with the CON mice (p < 0.05). Genes for glycan biosynthesis, which result in short-chain fatty acid synthesis, were enriched in the CB mice compared to the RB mice, which was correlated to a high abundance of Bacteroides. Overall, dietary RB and CB changed the gut microbiota of mice (p < 0.05).