Effects of a diet containing glutamine on the slaughter performance, meat quality, and skeletal muscle fiber types of feed-restricted yaks

Abstract

This experiment aimed to investigate the impact of the diet containing glutamine on muscle fiber types and meat quality of feed restriction yaks. Our findings show that the meat quality and slaughter performance in the feed restriction group decreased relative to the control group. However, diet containing glutamine improved slaughter performance by increasing carcass weight, dressing percentage, net meat weight, and net meat percentage. Moreover, it improved meat quality by increasing L* and reducing drip loss. In addition, dietary glutamine supplementation alleviated the increase in the fast-twitch fibers, abnormal glutamine metabolism, oxidative damage, and mitochondrial dysfunction. Mechanistically, the AMPK/Sirt1/PGC-1α/TAFM pathway might be implicated in glutamine alleviated the feed restriction-induced reduction in meat quality. In summary, our findings suggested that dietary glutamine supplementation of feed-restricted yaks can effectively improve the antioxidant capacity, slow-twitch fiber percentage, and the meat quality of the yak Longissimus thoracis muscle.