Association of differential meat quality traits with gut microbiota in Angus cattle and Xinjiang Brown cattle

. While most meat quality traits (MQTs) are investigated in Angus cattle (AG), the differences in MQTs and the relationship of MQTs with the gut microbiota between AG and Xinjiang brown cattle (XBC) have not yet been well elucidated. Fourteen heads of 24-month-old uncastrated AG and XBC males (7 in each group) reared under identical feeding condition were selected for MQT testing. The composition and structure of the gut microbiota were analysed by 16S rRNA gene sequencing of rectal faecal samples. The correlation between MQTs and the gut microbiota was analysed. The results showed that backfat thickness of XBC was significantly lower compared to AG, and the muscular fibre sectional area was significantly higher than that of AG. The composition of the gut microbiota showed that the relative abundance of the genus rc4_4 was significantly lower in XBC in relation to AG cattle ( P < 0.05) and Lefse analysis demonstrated that the family Peptostreptococcaceae were characteristic of the XBC gut. Thirteen genera of the gut microbiota significantly correlated with MQTs. The differential MQTs between Angus cattle and Xinjiang brow cattle related to fat metabolism/deposition were found to be associated with the relative abundance of certain gut microbial genera, which could serve as potential gut microbial biomarkers to assist in improving meat quality of Xinjiang brow cattle.