Modulation of meat colour by altering organismal oxidative phosphorylation and enhancing mitochondrial oxygen consumption via the intestinal flora after hybridisation

The selective breeding of beef cattle plays an important role in meeting the growing demand for beef and improving energy efficiency.The results showed that the blood glucose (GLU) levels of the crossbred improved SM group were higher than that of the S group. Compared with the S group, The relative abundances of Rikenellaceae_RC9_gut_group, Bacteroides, Bifidobacterium, Prevotellaceae_UCG-004, Lachnospiraceae_UCG-001 and Anaerosporobacter in Group M crossbred fattening cows were significantly greater (P<0.05). the TVFA content in the blood of the test cattle was significantly greater in Group S than in Group M (P<0.01).And the muscle redness of the test cattle in Group M was significantly greater than that in Group S (P<0.05).We found that Simmental cattle crossed with Mongolian cattle underwent intestinal alterations. resulting in the production of more VFAs and increasing the absorption of VFAs in the presence of Rikenellaceae_RC9_gut_group. This resulted in significantly higher GLU levels in Group M than in Group S, increased glycolysis and pyruvate metabolism in vivo, increased ATP . Increased oxygen consumption by mitochondria in Group M fattening cattle resulted in a reduction in the amount of available oxygen bound to Mb, giving the meat of the crossbred beef a bright red colour.