Dietary resveratrol improves meat quality in lambs via the rumen-muscle axis mediated by reshaped microbial metabolism.

Resveratrol (RSV) is a plant-derived polyphenol known to enhance host health and growth in animals. In this study, we used integrated metagenomic and metabolomic approaches to show that dietary RSV reshapes the rumen microbiome and its metabolism. Specifically, RSV upregulated volatile fatty acid (VFA) and amino acid synthesis pathways while suppressing methanogenesis in finishing lambs. These microbial metabolic changes propagated along a rumen-muscle axis, driving compositional improvements, as evidenced by elevated polyunsaturated fatty acids (gamma-linolenic acid) and key amino acids (Ser, Ala, Ile, and Leu), as well as enhanced meat quality traits, including reduced drip loss, increased eye muscle area, and improved color stability. Microbiota-muscle correlation analyses further linked the signature rumen microbes with muscle nutritional indicators. Our findings delineate a clear microbe-metabolite-tissue pathway through which RSV influences mutton quality, offering a mechanistic basis for microbiome-guided strategies to optimize meat production in ruminants.