Background: There have been many studies on the relationship between circRNAs and fat deposition. Although the liver is a central organ for fat metabolism, there are few reports on the relationship between circRNAs in the liver and fat deposition. Methods: In this study, we systematically analyzed circular RNAs in the liver of Ningxiang pigs, at four time points after birth (30 days, 90 days, 150 days and 210 days). Results: A total of 3705 circRNAs were coexpressed in four time periods were found, and KEGG analysis showed that the significantly upregulated pathways were mainly enriched in lipid metabolism and amino acid metabolism, while significantly downregulated pathways were mainly related to signal transduction, such as ECM–receptor interaction, MAPK signaling pathway, etc. Short time-series expression miner (STEM) analysis showed multiple model spectra that were significantly enriched over time in the liver. By constructing a competing endogenous RNA (ceRNA) regulatory network, 9187 pairs of networks related to the change in development time were screened. Conclusions: The expression profiles of circRNAs in Ningxiang pig liver were revealed at different development periods, and it was determined that there is differential coexpression. Through enrichment analysis of these circRNAs, it was revealed that host genes were involved in metabolism-related signaling pathways and fatty acid anabolism. Through STEM analysis, many circRNAs involved in fat metabolism, transport, and deposition pathways were screened, and the first circRNA–miRNA–mRNA regulation network map in Ningxiang pig liver was constructed. The highly expressed circRNAs related to fat deposition were verified and were consistent with RNA-Seq results.

The Ningxiang pig, a distinguished local breed in China, is recognized for its good meat quality traits. This study examines the proteomics of Ningxiang pigs at three developmental stages and delves into the upstream transcriptomics of these proteomics. Such an analysis facilitates a deeper understanding of the molecular interplay between proteins and transcriptomes in the Ningxiang pig muscle, influencing muscle growth and development. In this research, we analyzed the muscles of Ningxiang pigs at three developmental stages: 30 days in weaned piglets, 90 days in nursery pigs, and 210 days in late fattening pigs. There a total of 16 differentially co-expressed miRNAs (ssc-miRNA-1, ssc-miRNA-378, ssc-miRNA-143, ssc-miRNA-30e, etc.), 74 differentially co-expressed mRNA (PLIN3, CPT2, IGF2 and HSP90AB1, etc.) have been identified in the three stages. 572 differentially abundant proteins (DAPs) (APOC3, NDUFA2, HSPD1, ATP5E, PDHA1, etc.) were readily identified by comparing different time periods. According to the KEGG enrich pathway results that DAPs most enriched in growth and development pathways, immune mechanism pathways and maintaining functions of physical. Through short time-series expression miner (STEM) association analysis, a total of 571 negative miRNA-mRNA interaction pairs and 2 negative miRNA-mRNA-protein (Chr05_11955-Pig.17268.1-ATP5F1B, ssc-miR-194a-3p-Pig.15802.1-ACY1) interaction pairs were found. Our study provides a theoretical basis on molecular mechanism for the study of IMF deposition, muscle growth and immunity in Ningxiang pig breed.

CXCL14 (C-X-C motif chemokine ligand 14) is an important chemokine involved in infection and immunity and plays an important role in a variety of immune-related diseases. The 446 bp cDNA sequence of the CXCL14 gene in yaks was obtained. Additionally, the prokaryotic expression vector of the CXCL14 protein with a molecular weight of 27 kDa was successfully constructed and expressed. The proliferation activities and migration abilities of spleen macrophages were significantly inhibited after treatment with the CXCL14 protein at different concentrations (1, 10 and 20 μg/mL) (p < 0.05). Furthermore, the expressions of pro-inflammatory cytokines interleukin 1 beta (IL-1β), interleukin 6 (IL6), interleukin 8 (IL8) and interferon-α (TNF-α) were significantly increased (p < 0.05), but the expression of anti-inflammatory factor interleukin 10 (IL10) was significantly decreased (p < 0.05). The contents of inflammatory factors in the supernatant of cells were detected using ELISA, and it was also found that the contents of TNF-α, IL6 and cytochrome c oxidase subunit II (COX2) were significantly increased under different CXCL14 protein concentrations (p < 0.05). Finally, the exogenous addition of CXCL14 inhibited the activity, clonal formation and migration of hepatoma cells (HepG2). Additionally, after HepG2 cells were treated with 20 μg/mL CXCL14 protein for 12 h, 24 h and 36 h, the expression levels of BCL2 homologous antagonist/killer (BAK) and the BCL2-associated X apoptosis regulator (BAX) were increased to varying degrees, while the expression levels of hypoxia-inducible factor 1 subunit alpha (HIF1A), the mechanistic target of rapamycin kinase (mTOR) and cyclin-dependent kinase 1 (CDK1) genes decreased compared to the control group. In conclusion, the CXCL14 protein can inhibit the proliferation and migration of HepG2 cells by inducing the expression of macrophage pro-inflammatory factors and activating apoptosis-related genes to exert innate immunity. These results are helpful to further study the function of the CXCL14 protein and provide research data for the innate immune mechanism of yaks under harsh plateau environments.

Alleviating negative energy balance in perinatal yaks is a critical challenge for safeguarding the health of both dams and calves and achieving sustainable development of yak husbandry. While RPG supplementation represents an effective nutritional strategy, its transgenerational benefits, particularly the long-term effects on offspring calf development through maternal intervention, remain largely unexplored. In the present study, low-dose RPG (150 g d⁻¹, L-RPG, n = 6) markedly improved milk composition, elevating protein, fat, lactose, and gross energy contents (p < 0.05), and enhance calf weight gain (21.74%) with activation of the somatotropic axis (increased GH, IGF-1, etc.). Calves in this group also exhibited enhanced antioxidant capacity (higher SOD, CAT, and T-AOC) and improved immune regulation (lower IL-6, TNF-α). Multi-omics analyses revealed that L-RPG enriched beneficial taxa such as Solbacillus, Citricoccus, and Akkermansia muciniphila, optimized the hindgut microbiome, and upregulated serum metabolites including di-O-methylfraxetin and phenylalanyl-histidine. Integrated microbiota–metabolite profiling demonstrated significant cross-talk between the altered bacteria and metabolites. Collectively, supplementing dams with 150 g d⁻¹ RPG improves milk quality, modulates the calf gut microbiota, and reshapes host metabolism, thereby synergistically promoting offspring growth. Our findings provide a comprehensive “maternal nutrition–microbiota–metabolism” framework for understanding RPG’s mode of action and furnish both theoretical insights and practical guidance for dam–calf health management in yak production systems.

The yak (Bos grunniens) was domesticated in the high-altitude QTP. Research about their genetic diversity and population structure is limited. In this study, we resequenced the genome of 494 domestic yaks using Specific-Locus Amplified Fragment Sequencing (SLAF-seq). The survey was conducted on six populations sampled from isolated locations in China in order to analyze their structure and genetic diversity. These six domestic populations were clearly grouped into two independent clusters, with Jinchuan, Changtai, and Jiulong showing a tight genetic relationship with the wild yak. Nerve development pathways were enriched with GO enrichment analysis of 334 domesticated genes. Major genomic regions associated with the differentiation of domestic yaks were detected. These findings provide preliminary information on the yak genome variability, useful to understand the genomic characteristics of different populations in QTP.

Post-weaning diarrhea caused by Enterotoxigenic Escherichia coli (ETEC) is a major disease in piglets and leads to substantial economic losses in the swine industry. Compared to conventional lysozyme, yak stomach lysozyme (YSL) demonstrates distinctive resistance to pepsin, trypsin, high temperature, and acidic conditions. This study investigated the effects of dietary YSL supplementation on intestinal health in weaned piglets challenged with ETEC, utilizing metabolomics and proteomics. A total of 18 weaned piglets were randomly divided into three groups: control (C), diarrhea (D), and YSL treatment (YLT). Groups C and D were fed a basal diet, while the YLT group received the basal diet supplemented with YSL at a dosage of 100,000 U/kg following ETEC challenge. Following an acclimation period, piglets in groups D and YLT were orally challenged with ETEC, while group C received the same volume of sterile LB broth. The feeding trial lasted for 21 days before sample collection. The results demonstrated that dietary supplementation with YSL significantly reduced the diarrhea rate (p < 0.05). Compared with the D group, the YLT group exhibited significantly increased serum albumin levels (p < 0.05), along with a tendency toward greater villus height (p = 0.085) and higher serum glucose levels (p = 0.052), indicating an improvement in nutritional and metabolic status Metabolomic analysis identified 260 differentially abundant metabolites between the YLT and D groups (81 upregulated, 179 downregulated), which were predominantly enriched in pathways related to amino acid biosynthesis and metabolism, purine metabolism, and nucleic acid metabolism. Proteomic profiling revealed 571 differentially expressed proteins (237 upregulated, 334 downregulated). Upregulated proteins were mainly involved in arginine biosynthesis and base excision repair, while downregulated proteins were associated with the PPAR signaling pathway and Salmonella infection. In summary, dietary YSL supplementation alters the metabolic and proteomic profiles in the intestines of diarrheic piglets, potentially improving gut barrier function and nutrient utilization. This study offers novel insights into the potential of YSL as a promising feed additive for prevention of post-weaning diarrhea in pigs.