This study was conducted to investigate the effects of different strains and wheat bran on the fermentation quality, antioxidant activity, and bacterial community of mulberry leaf silage. Mulberry leaves were ensiled with Pediococcus acidilactici and Pediococcus pentosaceus (A), Bacillus subtilis and Bacillus licheniformi (DK), and Pediococcus acidilactici, Pediococcus pentosaceus, Bacillus subtilis, and Bacillus licheniformi (AK). Each treatment was supplemented with 10% wheat bran (fresh matter basis), and the strains were added in equal proportions for 7 days. The results indicated that the DK and AK groups exhibited higher dry matter (DM) content compared to the A group (p < 0.05). The A group (37.25 mg/g DM) and AK group (34.47 mg/g DM) demonstrated higher lactic acid content and lower pH (<4.40). Furthermore, the DK group had a significantly higher acetic acid content compared to the AK group (p < 0.05). Additionally, both the A and AK groups exhibited lower levels of ammonia-N content than the DK group (p < 0.05). The number of yeasts, molds, and coliform bacteria were low in mulberry leaf silage. Moreover, the antioxidant activity in the fermentation groups increased, with higher relative abundance of beneficial bacteria, Lactococcus and Lactobacillus, in the AK group. In summary, the AK group was observed to enhance fermentation quality and antioxidant capacity, leading to the establishment of a favorable microbial community composition.

Broilers face challenges in improving intestinal health and growth performance. Glutamine (Gln), a functional amino acid, exerts beneficial effects in promoting intestinal development and immunity. This study investigated the effects of graded levels of dietary Gln supplementation on the growth performance, intestinal morphology, immune indices, and cecal microbiota of broilers. Three hundred one-day-old Arbor Acres broilers (51.67±1.42 g) were assigned to five groups in a completely random design, with six replicates each group and 10 broilers in each replicate. The control group was fed the basal diet (Con), while the experimental groups were fed the basal diet containing 4 g/kg (Gln1), 6 g/kg (Gln2), 8 g/kg (Gln3), and 10 g/kg Gln (Gln4), respectively. The results showed that dietary Gln supplementation had quadratic effect on ADG, F/G, and final BW of broilers (P < 0.01), with higher average daily gain (ADG), final body weight (BW) in Gln2 group (P < 0.05). Dietary Gln supplementation quadratically improved serum immune indices of broilers (P < 0.01), with higher IgA, IgG, and IgM levels in Gln1 and Gln2 groups (P < 0.05). The Gln1 and Gln2 groups increased Bursa of Fabricius index at both d21 and d42 (P < 0.05). There was a quadratic effect of Gln on intestinal development (P < 0.01). Gln1 and Gln2 groups had higher duodenal VH and V/C, and the Gln2 group increased jejunal VH and V/C, and ileal VH at 21d (P < 0.05). Duodenal V/C improved in the Gln1 and Gln2 groups, and duodenal CD reduced in Gln1 group at 42d (P < 0.05). Gln1 and Gln2 groups increased cecal α-diversity (ACE, Chao1) at d21 (P < 0.05). PCoA revealed distinct cecal microbiota profiles across groups, with Gln-supplemented groups reducing pathogenic Escherichia-Shigella and Mucispirillum, while enriching beneficial genera (e.g., Ruminococcaceae_UCG-014, Barnesiella, and Butyricimonas) (P < 0.05). Collectively, dietary Gln-supplemented at 4-6 g/kg optimally enhances growth, immunity, and intestinal development in broilers, which is related to modulate cecal microbiota toward a beneficial composition.

Conjugated linoleic acid (CLA) isomers have been reported to reduce body weight and promote glycolipid metabolism in animals. In a preliminary study, we revealed that trans-10, cis-12-CLA (10,12-CLA) plays an important role in modulating lipid metabolism in chickens. However, the underlying mechanism remains unclear. In this study, we constructed an isolated in vitro model with primary chicken hepatocytes to investigate the effect of 10,12-CLA on lipid metabolism. 10,12-CLA inhibited lipid accumulation by decreasing the mRNA expression of sterol regulatory element-binding protein-1c (SREBP-1c), SREBP2, 3‑hydroxy-3-methylglutaryl-CoA reductase (HMGCR), fatty acid synthase (FAS), adipose triacylglyceride lipase (ACC), and lipoprotein lipase (LPL) and increasing the mRNA expression of peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyltransferase 1 (CPT1) and adipose triacylglyceride lipase (ATGL). Furthermore, 10,12-CLA treatment activated the protein expression of extracellular signal-regulated kinase 1/2 (ERK1/2) and AMP-activated protein kinase (AMPK), whereas treatment with the ERK1/2 inhibitor U0126 reversed the inhibitory effects of 10,12-CLA on lipid accumulation by blocking the ERK1/2-AMPK pathway, leading to increased lipid accumulation and triglyceride content in primary chicken hepatocytes. These findings suggest that in chicken hepatocytes, 10,12-CLA alleviates hepatocyte lipid deposition by activating the ERK1/2-AMPK pathway, promoting fatty acid oxidation and reducing lipid synthesis, revealing the potential mechanism through which 10,12-CLA regulates hepatic lipid metabolism in chickens.

This experiment was conducted to investigate the effects of mulberry leaf powder (MLP) on alleviating fatty liver hemorrhagic syndrome (FLHS) in laying hens. A total of 180 healthy 33-week-old Hy-Line Gray laying hens were randomly assigned to 3 groups, with 6 replicates per group and 10 chickens per replicate, and fed a basal diet (CON), high-energy-low-protein (HELP) diet (FLHS), and HELP + 5% MLP diet (MLP), respectively. The experiment lasted 56 days. Results showed that the HELP diet successfully induced FLHS, characterized by an increased liver index, hepatic steatosis, and oxidative stress (P < 0.05). MLP significantly alleviated FLHS-induced hepatic steatosis, and enhanced antioxidant capacity (superoxide dismutase, catalase, glutathione peroxidase, total antioxidant capacity, and glutathione) in serum and liver (P < 0.05). Transcriptomic analysis identified 102 differentially expressed genes, whose expression was increased by FLHS but reversed by MLP, including SREBF1, SLC27A4, PLIN2, ACOT13, APOA4, GLRX, and MSRB1, which mainly participate in lipid droplet dynamics and redox homeostasis. qRT-PCR confirmed that upregulated expression of lipogenic genes (such as FASN, ACACA, SCD, and ELOVL6) and the downregulated expression of oxidative stress-responsive genes (SOD1 and GPX1) in the FLHS group were normalized by MLP (P < 0.05), accompanied by increased expression of PPARα, CPT1A, and CD36 (P<0.05). 16S rRNA sequencing revealed that MLP reduced the abundance of Desulfovibrio, Rikenellaceae_RC9_gut_group, Intestinimonas, and Shuttleworthia, and enriched Faecalibacterium and Bifidobacterium in the cecum of FLHS laying hens (P < 0.05). Furthermore, MLP increased acetate, propionate, and butyrate levels, and decreased isobutyrate and isovalerate levels (P < 0.05). Correlation analysis showed that cecal acetate, propionate, butyrate, Faecalibacterium and Bifidobacterium were positively correlated with hepatic antioxidant enzyme activities (P < 0.05), and negatively correlated with hepatic lipogenic gene expression, hepatic lipid deposition and oxidative stress markers (P < 0.05). These findings indicated that MLP alleviated hepatic lipid metabolism disorders and oxidative stress in FLHS laying hens, which might be achieved by modulating gut microbiota structure and short-chain fatty acid production.

This study investigated the effects of different duck fat (DF) levels on growth performance, intestinal microbiota, and meat quality in Cherry Valley ducks. A total of 120 one-day-old male Cherry Valley ducks (initial body weight 75.00±2.93 g) were randomly allocated to three treatment groups, with 5 replicates per group and 8 ducks per replicate, and fed diets supplemented with 3%, 6%, or 9% DF (DF3, DF6, DF9) respectively for 42 days. It showed that 6% DF level (DF6) increased the body weight, average daily gain and average daily feed intake from days 1–14 (P < 0.05), and significantly increased the intramuscular fat (IMF) content in breast muscle at 42d, by increasing lipogenesis gene expression (P < 0.05). Lipidomics analysis showed that DF6 promoted triglyceride (TG) accumulation in breast muscle by modulating key lipid metabolism pathways (P < 0.05). 16S rRNA sequencing results revealed that DF6 increased the enrichment of butyrate-producing bacteria (such as Lachnospiraceae), and decreased the abundance of gram-negative and potentially pathogenic bacteria in cecum (P < 0.05). Correlation analysis indicated that the abundances of Lachnospiraceae was positively correlated with the contents of TG metabolites, IMF contents, and lipogenesis genes expression in breast muscle (P < 0.05). In conclusion, this study demonstrated that dietary 6% duck fat supplementation enhanced meat quality by enriching cecal Lachnospiraceae abundance, increasing butyrate, and activating the PPARγ-mediated intramuscular lipid deposition. These findings provide a novel nutritional strategy for enhancing duck meat quality through the gut-muscle axis.