This study evaluated the effects of dietary supplementation with N-Carbamylglutamate (NCG) on growth performance, immune function, intestinal metabolites, and microbiota in Danzhou chickens. In a 35-day feeding trial, a total of 480 one-day-old female chicks were randomly assigned to a control group (basal diet) and three experimental groups supplemented with 400, 800, or 1200 mg/kg NCG, with 120 chicks in each group (n = 120). The results demonstrated that NCG, particularly at 400 mg/kg, significantly improved growth parameters, including average daily gain and feed conversion ratio, while enhancing immune function by increasing serum levels of immunoglobulins (IgA, IgY) and malate dehydrogenase (p < 0.05). Metabolomic analysis revealed that NCG modulated key pathways such as sphingolipid metabolism and mTOR signaling pathway, leading to significant changes in metabolites including L-arginine, ceramide, and docosahexaenoic acid (p < 0.05). 16S rDNA sequencing indicated that NCG induced structural shifts in the gut microbiota, primarily affecting Bacteroidota and Firmicutes, with several bacterial genera showing strong correlations with the observed metabolic changes (p < 0.05). Mechanistically, NCG promotes growth by facilitating arginine synthesis via the urea cycle and activating the mTOR signaling pathway, while its regulation of sphingolipid metabolism enhances immunomodulatory capacity. In conclusion, NCG enhances feed efficiency and immune competence by orchestrating the gut microbiota-metabolite network, demonstrating its potential for poultry production.

This study evaluated the effects of supplementing Alpinia katsumadai and Wurfbainia vera extracts on the growth performance, antioxidant capacity, intestinal metabolites, and microbiota of Danzhou chickens. Using Danzhou broilers, we examined the individual or combined inclusion of Alpinia katsumadai and Wurfbainia vera extracts in a 2 × 2 factorial layout. Four hundred and eighty female dual-purpose chickens were randomly assigned to four treatments (six replicates of 20 chicks each): control basal diet (CON), basal + 600 mg kg⁻¹Alpinia katsumadai (T1), basal + 600 mg kg⁻¹ Wurfbainia vera (T2), or basal + 600 mg kg⁻¹ Alpinia katsumadai + 600 mg kg⁻¹ Wurfbainia vera (T3). All treatments differed significantly from CON. For intestinal morphology, T1, T2, and T3 increased jejunal villus height and villus-to-crypt ratio while reducing crypt depth. T1 exceeded CON (p < 0.05), and an interaction was detected. T1 raised the abundances of Bacteroidota, Bifidobacterium, Tidjanibacter, and Phocaeicola relative to CON (p < 0.05). T3 exhibited higher activities of glutathione peroxidase and catalase than CON, T2, and T1 (p < 0.05). Metabolomically, T1, T2, and T3 elevated intestinal Menaquinone-9, lecithin, and L-galactono-1,5-lactone versus CON (p < 0.05). T3 lowered 3-(R)-Hydroxyoctadecadienoic acid and 9-(R)-Hydroxyoctadecadienoic acid versus CON and T1, and increased eugenol versus CON (p < 0.05). Overall, T1 and T2, especially in combination, enhance antioxidant capacity, improve gut morphology, promote beneficial microbiota and activate health-related metabolic pathways in Danzhou broilers.

The reproductive efficiency of modern breeding sows is commonly restricted by a mismatch between high genetic reproductive potential and insufficient voluntary feed intake during critical physiological periods. This review comprehensively examines the physiological, nutritional, and management mechanisms regulating feed intake in sows and their implications for reproductive performance, synthesizing recent advances across neuroendocrine regulation, metabolic signaling, immune-related pathways, and precision feeding strategies. We construct an integrated framework involving three core dimensions: (1) Physiological regulation: the hypothalamic–pituitary–adrenal, hypothalamic–pituitary–gonadal, and hypothalamic–pituitary–spleen axes functionally interact via shared neuroimmune pathways within the hypothalamic–pituitary–immune axis, coordinately regulating feeding patterns and reproductive cyclicity through core hormonal and inflammatory signaling molecules. Perinatal stress induces pro-inflammatory cytokine secretion, activates the intestinal JAK-STAT3 pathway, and upregulates intestinal hepcidin expression, impairing intestinal barrier integrity and triggering persistent inflammation. These peripheral inflammatory signals modulate hypothalamic neuropeptide Y and Proopiomelanocortin expression, forming a negative feedback loop that suppresses feeding behavior. (2) Nutritional regulation: dietary nutrients and specific flavor compounds reshape intestinal satiety signaling, improving piglet growth performance and survival rates, while optimized dietary composition and functional additive supplementation enhance sow feed intake capacity. (3) Management strategies: standardized feeding regimes and optimal rearing environments regulate nutrient digestion and gut hormone secretion. Major knowledge gaps include the translational potential of precision nutrition approaches, biomarker validation for feed intake monitoring, and the scalability of integrated interventions under commercial production conditions. This review provides a multidimensional framework integrating physiological, nutritional, and management strategies to enhance sow feed intake, offering theoretical insights and practical guidance for sustainable pig production.

This study evaluated dose-dependent effects of dietary N-carbamylglutamate (NCG) on muscle growth, nutrient composition, and metabolic profiles in Danzhou chickens. A total of 480 one-day-old female Danzhou chicks were randomly assigned to diets supplemented with 0, 400, 800, or 1200 mg/kg NCG for 35 days and slaughtered at 35 days of age. NCG at 400–800 mg/kg improved growth performance, increased crude protein and free amino acids (arginine, methionine), and altered fatty acid composition in a muscle-specific manner, with increased breast-muscle MUFA and decreased leg-muscle arachidonic acid and DHA; total PUFA did not differ. Histological analysis showed that NCG increased leg-muscle fiber cross-sectional area and Feret diameter, accompanied by a reduction in fiber density. Mechanistically, NCG altered the mRNA expression of IRS2, IGF1, MyoG, AKT1, and FOXO1 in a manner consistent with modulation of the IGF-1/IRS2/PI3K/Akt/FoxO1 axis. Metabolomics suggested an association with purine metabolism; however, this finding is exploratory and does not establish causality. Integrated multi-omics revealed crosstalk between purine and lipid metabolism. Among the doses tested, 800 mg/kg produced the largest response for several endpoints; however, no formal dose-optimization model was fitted, and the optimal dose remains to be determined. The 1200 mg/kg dose did not further improve most endpoints, indicating a nonlinear dose response. This study provides the first multi-omics evidence demonstrates that NCG modulates muscle growth, nutrient composition, and metabolic profiles in indigenous chickens through coordinated regulation of anabolic signaling, purine metabolism, and lipid remodeling. Direct meat-quality measurements were not performed; therefore, effects on eating quality, technological quality, oxidative stability, and consumer preference remain to be established.

This study investigated the effects of graded dietary curcumin supplementation on production performance, antioxidant capacity, immune status, intestinal barrier function, and cecal microbiota in late-laying hens. A total of 480 61-week-old Jingfen No. 1 laying hens were randomly allocated to four groups with six replicates of 20 birds each: a basal diet control (CG) and diets supplemented with 100, 200, or 400 mg/kg curcumin (CN1, CN2 and CN3) for 35 days. Curcumin supplementation significantly increased average egg weight (p < 0.05). Serum catalase concentration and immunoglobulin levels (IgM, IgA, and IgY) were elevated, whereas malondialdehyde, interleukin-6, interleukin-10, and tumor necrosis factor-α levels were reduced in a dose-dependent manner (p < 0.05). Similar improvements were observed in the jejunum, including increased glutathione peroxidase and catalase concentrations and reduced inflammatory cytokines. Birds in the CN3 group exhibited greater villus height and villus-to-crypt ratio, lower crypt depth, and upregulated mRNA expression of tight junction proteins (ZO-1, Occludin, and Claudin-1) (p < 0.05). Curcumin also modulated the cecal microbiota by enriching beneficial butyrate-producing bacteria (Lactobacillales, Faecalibacterium, Odoribacter, Roseburia, and Phascolarctobacterium) and reducing pathogenic Staphylococcus and Bilophila. Overall, dietary curcumin improved egg quality, antioxidant and immune functions, intestinal health, and microbial composition in late-laying hens.

To investigate the effects of low net-energy (NE) diets on intestinal health in Tunchang pigs, 96 animals (25.40 ± 1.11 kg) were randomly assigned to four dietary treatment groups with NE levels of 9.82 (CG), 9.57 (EY1), 9.32 (EY2), and 9.07 (EY3) MJ/kg. Each group consisted of six replicates with four pigs per replicate. The experiment lasted for 63 days. The results showed that compared with the CG, the EY2 increased jejunal villus height and villus height-to-crypt depth ratio, as well as reduced crypt depth in the colon (p < 0.05). Both the EY1 and EY2 demonstrated improved intestinal barrier function through upregulation of zonula occludens-1 and occludin expression in the jejunum, zonula occludens-1 in the ileum, and zonula occludens-1, occludin, and claudin-1 in the colon (p < 0.05). Furthermore, EY2 significantly increased the activities of superoxide dismutase, glutathione peroxidase, and catalase, while reducing malondialdehyde content in both the jejunum and colon (p < 0.05). EY2 showed significantly downregulated relative expression of pro-inflammatory cytokines, including interleukin-1β, tumor necrosis factor-α, and interleukin-6, in the jejunum, ileum, and colon (p < 0.05). Microbial and short-chain fatty acid (SCFA) analyses showed that the EY2 increased the abundance of beneficial bacteria such as Faecalibacterium, CF231, Coprococcus, Ruminococcus, and Blautia and elevated the concentrations of acetate, propionate, and butyrate. In summary, reducing dietary NE levels to no less than 9.32 MJ/kg improved intestinal health by modulating the gut microbiota and increasing SCFA production.