Zeqing Lu

This study aimed to investigate the effects of dietary tea polyphenols (TPs) supplementation on growth performance and meat quality. A total of 120 pigs ([Yorkshire × Landrace] × Duroc) aged 150 days with similar body weights (74.29 ± 0.55 kg), comprising equal numbers of females and castrated males, were randomly assigned to two treatments, each with three pens of 20 pigs: The Control group received a basal diet, and the TP group received the basal diet supplemented with 2000 mg/kg tea extract containing 15% TP. A 7-day adaptation preceded the 60-day feeding period. At the end of the experiment, the final bodyweight of the pigs was measured and six pigs per treatment were selected for sampling. The results showed that: (1) growth performance did not differ significantly, although feed-to-gain ratio and average daily feed intake were numerically lower in the TP group; (2) carcass weight, backfat thickness, and muscle alanine increased, whereas longissimus dorsi lightness and yellowness decreased (p < 0.05); (3) serum total superoxide dismutase and hepatic catalase and glutathione peroxidase activities increased (p < 0.05); (4) Chao1 richness and Shannon diversity were unchanged, and genus-level PCoA showed partial but non-significant separation of the colonic microbial communities (R = 0.1685, p = 0.090). Nevertheless, TP supplementation selectively altered specific bacterial taxa, with lower relative abundances of Pseudomonadota, Escherichia–Shigella, and Ligilactobacillus and higher relative abundances of Solobacterium, norank_f__p-2534-18B5_gut_group, and [Ruminococcus]_gauvreauii_group; and (5) Catenisphaera was positively correlated with serum total superoxide dismutase activity (p < 0.01), whereas the TP-enriched norank_f__p-2534-18B5_gut_group was positively correlated with muscle alanine content (p < 0.05). This study demonstrates concurrent antioxidant, meat-quality, and microbial responses to a TP-containing diet, supporting mechanistic research on a potential gut–liver–muscle association and refinement of supplementation strategies that balance antioxidant benefits with carcass fat deposition.

Background: The early-life gut microbiota plays a critical role in programming intestinal barrier function and immune homeostasis, with profound implications for long-term host health. However, the effects of early-life compound probiotic intervention on the maturation of intestinal barrier function and the underlying molecular mechanisms remain incompletely understood, particularly in large-animal models relevant to human physiology. Methods: In this preclinical study, 3627 neonatal piglets—a well-established translational model for human infant gut development—were orally administered a novel compound probiotic formulation comprising Bifidobacterium longum subsp. infantis BZ, Lactobacillus plantarum LZ, and Pediococcus acidilactici PZ during early life. A total of 1512 fecal samples collected at seven time points from birth to day 180 were analyzed by 16S rRNA sequencing, and 525 samples from three developmental windows (days 10, 25, and 70) were subjected to LC-MS-based metabolomics. The candidate metabolite indole-3-lactic acid (ILA) was further mechanistically validated in a DSS-induced colitis mouse model and in IPEC-J2 cells. Results: Early-life probiotic intervention significantly enhanced intestinal barrier integrity, as evidenced by improved intestinal morphology and upregulated expression of tight junction proteins—zonula occludens-1 (ZO-1), occludin (OCLN), and Claudin-1 (CLDN1)—in the jejunum (p < 0.05). Notably, intervention at birth was more effective than post-weaning administration, and two administrations (birth + weaning) yielded superior outcomes compared with a single administration (p < 0.05). Microbiome analysis revealed enhanced microbial diversity and enrichment of beneficial genera during the juvenile-to-adult transition (p < 0.05). Metabolomic profiling identified ILA as a signature metabolite consistently elevated by probiotic supplementation. Conclusions: These findings provide evidence that early-life compound probiotic intervention is associated with improved intestinal barrier maturation, with ILA identified as a key candidate metabolite that may mediate this effect, as supported by functional validation in murine and cellular models. This provides a mechanistic rationale for probiotic-based strategies to support intestinal health in human infants during critical developmental windows.

The aim of this study was to elucidate the dynamic characteristics of the Taihe Silky Fowl (TSF) intestinal microbiota systematically and predict their biological functions from hatching to market through large-scale sampling and 16S rRNA gene sequencing of a total of 288 samples taken at 8 timepoints from 3 intestinal regions to provide a theoretical basis for optimizing the intestinal microbiota to promote growth performance and intestinal health through artificial interventions on the basis of different growth ages and intestinal regions. The alpha and beta diversity of the intestinal microbiota changed significantly with age in different intestinal regions. In terms of alpha diversity, the ACE index and Shannon index followed the order cecum > rectum > duodenum, while the Simpson index followed the order rectum and duodenum > cecum. The PCoA plots revealed significant differences in beta diversity at different ages and in intestinal regions. The core phyla (top 5) in the TSF microbiota were Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Cyanobacteria. The core genera (top 10) were Lactobacillus, Bacillus, Escherichia-Shigella, Alistipes, norank_o__Clostridia_UCG-014, Bacteroides, Faecalibacterium, norank_f__Ruminococcaceae, Enterococcus and Streptococcus. Additionally, the degree centrality of the cecal microbiota rapidly increased from hatching to 1 week of age, then rapidly decreased from 1 to 2 weeks of age, where it remained relatively stable until 21 weeks of age, whereas the betweenness centrality exhibited the opposite trend; the closeness centrality decreased continuously with age. The functions of the cecal microbiota varied at different ages, and the central functions were nucleic acid metabolism and protein synthesis at 0 weeks of age and carbohydrate metabolism and quorum sensing at 9 weeks of age. In conclusion, the diversity, structure, composition, community relationships and functions of the intestinal microbiota in Taihe Silky Fowl dynamically changed with age in different intestinal regions.

Probiotics are widely used as dietary additives to strengthen gut barrier function, shape microbiota composition, regulate host metabolism, and promote overall health. To enhance probiotic delivery and microbial viability, this study evaluated a liquid feeding system supplemented with a probiotic consortium (Bifidobacterium infantis, Lactobacillus plantarum, and Pediococcus acidilactici) in nursery piglets. A 60-day trial involving 270 piglets (16.84 ± 0.12 kg) compared three diets: solid feed (Dry), liquid feed (Liq), and probiotic-enriched liquid feed (Pro). Compared to the Dry and Liq groups, probiotic supplementation significantly improved growth performance, with the average daily gain increasing by over 17.86% (p < 0.01) and the average daily feed intake increasing by more than 6.08% (p < 0.05). The feed conversion ratio was reduced by up to 8.08% (p < 0.05), indicating improved feed efficiency. The Pro group also exhibited elevated tight junction protein expression (p < 0.05), increased colonic short-chain fatty acid levels (p < 0.01), and decreased serum biomarkers of intestinal permeability (p < 0.05). The 16 S rRNA sequencing indicated the probiotic-driven colonization of B. infantis and L. plantarum and the suppression of opportunistic pathogens. Metabolomic analyses revealed enhanced colonic tryptophan metabolism, evidenced by elevated kynurenic and xanthurenic acid levels. Additionally, serum-targeted metabolomics and in vitro experiments confirmed that B. infantis and L. plantarum effectively converted tryptophan into indole-3-lactic acid, promoting its accumulation in piglet serum and colons. These results deepen our understanding of the mechanisms by which probiotics and tryptophan metabolism enhance intestinal health, providing a foundational platform for the application of probiotic-based interventions in livestock production.

This study was designed to investigate the effects of Fermented Broussonetia papyrifera (FBP) on growth performance, meat quality, and the expression of meat quality-related genes in Taihe black-bone silky fowl (TBsf). In the present study, 360 ninety-day-old TBsfs (body weight = 781 ± 0.85 g) were divided into 4 groups with 5 replicates (18 hens per replicate), of which the control group was fed the basal diet and the 3 experimental groups were supplemented with 2%, 4%, and 8% FBP. After 75 days, 8 TBsfs in each group were randomly selected to collect their left pectoral muscles for meat quality and transcriptome analysis. Compared with the control group, 4% FBP improved the growth performance and meat quality of TBsf, evidenced by the increasing trend in the ratio of feed intake to body weight gain (P = 0.082), and significantly increased equivalent umami concentration (EUC), amino acid, and nucleotide compositions (P < 0.05). In addition, the remaining meat quality indices including the yellowness of meat color, muscle fiber density, and shear force were also improved in the 4% group (P < 0.05), with consistent improvements in the 8% FBP group. The transcriptome results indicated that FBP may regulate muscle fiber growth and development through the Forkhead box O (FoxO) and mitogen-activated protein kinase (MAPK) signaling pathways, and regulate meat color through the adipocytokine signaling pathway. Weighted gene coexpression network analysis (WGCNA) further revealed the candidate genes involved in amino acid metabolism and nucleotide metabolism, and the trends of these genes were inflecting with the 4% FBP group. Together, these results suggest that FBP significantly improved the growth performance, and meat quality of TBsf, with 4% FBP as the optimal addition ratio, and the transcriptome analysis revealed the mechanism of gene regulation.