Feeding Diqing Tibetan pigs with 50% of soybean meal replaced by walnut meal can reduce subcutaneous fat deposition and promote intramuscular fat accumulation

作者：Xinpeng Li, Siqi Jin, Hong Hu, Yi Lan, Bin Ni, Jianglong Su, Shuyuan Luo, Lei Tan, Yong Zhang, He Huang, Yining Xu, Jiayue Yang, Chuhuan Zhou, Keyan Chen, Shihao Li, Bingkun Liang, S. Bai, Kang Zhang, Hongbin Pan, Xinxing Dong, D. Yan · 发表于：Frontiers in Microbiology · 年份：2026 · DOI：10.3389/fmicb.2026.1794046 · 被引用次数：1 · 研究领域：Medicine

Background Protein feed resource shortage is a major constraint to the sustainable development of the livestock industry and a bottleneck problem hindering the growth of the Tibetan pig industry in China's Qinghai-Tibet Plateau region. Walnut meal, rich in protein, holds promise as a substitute for soybean meal. However, the effects and underlying mechanisms of walnut meal substitution on Tibetan pigs in Diqing remain unclear. Results The study showed that substituting 50% of soybean meal with walnut meal in the diet of Diqing Tibetan pigs significantly reduced backfat thickness and increased intramuscular fat content (P < 0.05). Integrated multi-omics analyses, including metagenomics, transcriptomics, and lipidomics, revealed that walnut meal substitution significantly reduced the abundance of Clostridium butyricum in the cecum of Diqing Tibetan pigs. The reduction in Clostridium butyricum was linked to the lipolytic capacity of subcutaneous adipose tissue, potentially facilitating the breakdown of triglycerides into free fatty acids (FFAs), which are then released into the bloodstream. When these free fatty acids are transported to muscle tissue, the muscle exhibited inhibited oxidative metabolism (e.g., a decrease in acylcarnitine metabolites), while showing an upregulation in the expression of genes related to adipocyte differentiation (e.g., MEDAG, VDR) and triglyceride synthesis (e.g., PPARGC1A, ANGPTL4). Ultimately, these processes may contribute to the synthesis and s...