This study investigated the metabolite dynamic changes and transformation pathways in Diqing Tibetan pig (DTP) hams during fermentation (0, 30, 90, 180, 360, 540 d) by widely targeted metabolomics. A total of 873 metabolites in 17 subclasses were detected, with significant changes in 448 metabolites. Additionally, 65 key metabolites were found to be involved in the top 10 pathways, with the top pathways for metabolite markers in mature hams including protein metabolism (2-oxocarboxylic acid metabolism, tryptophan metabolism and amino acid biosynthesis) and lipid metabolism (unsaturated fatty acid biosynthesis and linoleic acid metabolism). Overall, the unique DTP ham taste, flavor, and nutritional value may be contributed to by the significant accumulation of essential amino acids, MSG-like amino acids, free fatty acids (arachidonic acid, docosahexaenoic acid, and eicosapentaenoic acid), citric acid, oxaloacetic acid, succinic acid, and vitamin B. This study facilitates a comprehensive understanding of metabolic profiling and the transformation pathways of DTP hams during fermentation, providing novel insights into the biochemical mechanisms underlying traditional Tibetan pig hams, bridging traditional knowledge with modern omics technologies.

Chicory holds considerable promise as a nutritious feed alternative. This study investigated the associations of dietary inclusion of 10% fresh chicory (dry-matter basis) with growth performance, meat quality, cecal microbiota, and muscle metabolite profiles in Diqing Tibetan pigs using integrated metagenomic and widely targeted metabolomic analyses. Thirty-six castrated male growing–finishing Diqing Tibetan pigs were randomly allocated into control and chicory-supplemented groups. Our findings revealed that the 10% fresh chicory inclusion did not compromise growth performance. Moreover, the chicory diet was associated with a significant enrichment of Prevotella sp., Bacteroides thetaiotaomicron, and Bacteroides uniformis within the cecum. Importantly, these specific microbial shifts exhibited correlations with alterations in the muscle metabolite profile. We observed that the chicory intervention was accompanied by elevated levels of glycerol 3-phosphate and glycerophospholipids, alongside a reduction in acylcarnitines. These exploratory associations suggest a potential link to shifted triglyceride metabolism, which corresponds to the significantly higher intramuscular fat content observed in the experimental group (5.89 ± 0.98) versus the control (4.23 ± 0.23). Overall, dietary inclusion of 10% fresh chicory was associated with changes in the cecal microbiota and muscle metabolome and supports further evaluation of fresh chicory as a forage ingredient in pig diets.

Feed scarcity constrains livestock production, particularly on the Qinghai-Tibet Plateau. The effects of green alfalfa (GA) on Diqing Tibetan pig performance remain unclear. This study aimed to evaluate GA effects on Diqing Tibetan pig performance and to explore the potential underlying mechanisms through integrated metagenomic, transcriptomic, and metabolomic analyses. Thirty-six Diqing Tibetan pigs were randomly assigned to two groups and fed either a basal diet or a diet containing 90% basal diet and 10% GA. GA did not adversely affect growth performance but reduced 6–7 rib backfat thickness and muscle water loss rate by 19.79% (FDR = 0.027) and 17.80% (FDR = 0.036), while increasing muscle moisture content by 3.51% (FDR = 0.036). GA increased cecal microbial alpha diversity, Bacteroidota-related taxa, and functional genes related to lipid and vitamin metabolism, while decreasing Bacillota and Lactobacillus johnsonii. In the longissimus dorsi, TNNI1, MYL2 and MYL3 were upregulated, whereas FOS and FOSB were downregulated; GA increased vanillyl alcohol, L-histidine, LPE (0:0/22:5), and licochalcone B, but decreased glyceryl monostearate, benzaldehyde, cortisol, tryptamine, 4-ethyloctanoic acid, 8-methylnonanoic acid, and purine. Overall, 10% GA reshaped gut microbial, muscle transcriptomic, metabolomic profiles and collectively influenced 6–7 rib backfat thickness and muscle water-holding capacity in Diqing Tibetan pigs.

Alternative feed ingredients may alter intestinal structure and function. We examined jejunal, ileal, and cecal responses in Large Diqing Tibetan pigs fed a control diet or one in which walnut cake replaced 50% of soybean meal. Two pigs were sampled from each of three pens per treatment. Intestinal morphology was assessed histologically, and RNA sequencing data from 8 jejunal, 12 ileal, and 10 cecal samples retained after screening were analyzed by voom–dream, differentially expressed gene (DEG) enrichment analysis, and gene set enrichment analysis (GSEA). The 50W group showed higher villus-related indices in the jejunum and ileum and greater cecal mucosal thickness and crypt depth. The screened-sample analysis identified 103, 67, and 1979 DEGs, respectively. Pathway analyses associated jejunal responses with nutrient metabolism, ion transport, and epithelial organization; ileal responses with DNA replication, cell cycle, and epithelial renewal; and cecal responses with extracellular matrix organization and cell adhesion. Although jejunal and cecal DEG counts were sensitive to sample inclusion, principal pathway-enrichment directions were broadly maintained in full-sample and leave-one-pen-out analyses. RT-qPCR results for five selected genes showed concordant directions of expression change with the corresponding RNA-seq results.