We aimed to investigate the role of capsaicin (CAP) in modulating lipopolysaccharide (LPS)-induced hepatic and intestinal inflammation, oxidative stress, and its colonic microflora in mice. Thirty healthy male Kunming mice with similar body weights were randomly assigned to three groups: the control group (CON), the LPS group, and the CAP group, with ten mice in each group. The CON and the LPS groups received a daily dose of normal saline, respectively, while the CAP group received an equivalent dose of CAP. On the 28th day of the experiment, the LPS and the CAP groups were intraperitoneally injected with LPS, while the CON group was injected with an equal volume of normal saline. The results lead to the following conclusions. Compared to the LPS group, CAP improved the loss of hepatic lobular structure and significantly increased the duodenal villus length and ratio of villus length to crypt depth. CAP increased hepatic and colon interleukin-10 (IL-10) and decreased IL-6, IL-1β, and tumor necrosis factor (TNF-α) levels. CAP also increased hepatic catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) expression, and decreased malondialdehyde (MDA) levels. CAP significantly increased the relative abundances of Mucispirillum, Helicobacter, Prevotellaceae-UCG-001, Colidextribacter, unclassified-f-Oscillospiraceae, and Odoribacter, some of which were closely related to hepatic and colonic immune and oxidative markers. CAP also decreased the overall content of short-chain fatty acids, except for propionic acid. Overall, CAP can regulate the colon microbiota and exert anti-inflammatory and antioxidant effects. Whether CAP exerts its anti-inflammatory and antioxidant effects by modulating the colonic microflora, mainly Mucispirillum spp. and Helicobacter spp., requires further investigation.

Triticale (Triticosecale Wittmack) is a versatile forage crop valued for its high yield, balanced nutrition, and environmental adaptability. However, the dough-stage triricale has higher dry matter and starch content but lower water-soluble carbohydrate levels than earlier stages, posing fermentation challenges that may impair silage quality. This study aimed to investigate the effects of lactic acid bacteria inoculation on the fermentation quality, bacterial community, and metabolome of whole-plant triticale silage at the dough stage. Fresh triticale was ensiled for 30 days without or with an inoculant containing Lactiplantibacillus plantarum and Streptococcus bovis. Fermentation quality, bacterial succession, and metabolic profiles were analyzed at multiple time points. Inoculation significantly improved fermentation quality, characterized by a rapid pH drop, increased lactic acid production, and better preservation of fiber components. Microbial analysis revealed that inoculation successfully established Lactobacillus as the dominant genus while suppressing spoilage bacteria like Enterobacter and Clostridium. Metabolomic analysis on day 30 identified numerous differential metabolites, indicating that inoculation primarily altered pathways related to amino acid and purine metabolism. In conclusion, inoculating dough-stage triticale with this LAB combination effectively directs the fermentation trajectory. It enhances silage quality not only by optimizing organic acid profiles and microbial succession but also by modulating key metabolic pathways, ultimately leading to improved nutrient preservation.

Calf intestines are colonized by rich and complex microbial communities, playing a crucial role in animal physiology, metabolism, nutrition, and immune function. In this study, we provide insight into the composition of fecal microbial bacteria and fungi, respectively, as well as the cross-kingdom interactions. We investigated the intestinal microbiota of different breeds of calves by characterizing the bacterial and fungal communities in the rectal feces of Holstein calves and German Simmental × Holstein cross F1 generation (GXH) using 16S rRNA and ITS amplicon sequencing techniques. PICRUSt2 (version 2.2.0) were used to determine microbial diversity and function and explore the reasons why Holstein calves are more susceptible to diarrhea. The results revealed no significant difference in the diversity of fecal microbiota among the groups (p > 0.05). We identified Firmicutes, Bacteroidetes, and Proteobacteria as the dominant bacterial phyla in the fecal bacterial communities of the two breeds of calves. Ascomycota and Basidiomycota play important roles in the fungal community but differ in relative abundance. Bacteroides was the dominant genus at the group level for calf fecal microbiota in both breeds. The relative abundance of Prevotella, Escherichia-Shigella, Peptostreptococcus, and Butyricicoccus was higher in Holstein calves, and the relative abundance of Faecalibacterium, Megamonas, Butyricicoccus, and Alloprevotella was lower than GXH group. Aspergillus and Cladosporium were the dominating genera of fecal fungi in both groups of calves. LEfSe analysis revealed 33 different bacteria and 23 different fungi between the two groups, with more differential strains found in GXH. In addition, the feces fungi-bacteria interkingdom interactions varied among breeds. Thus, the composition and structure of bacterial and fungal communities in calf feces varied by breed, indicating a potential association between breed and microbial communities. We also found differences in the network between bacterial–fungal kingdoms. We explain the reasons for Holstein calves being more prone to diarrhea. This indicated that breed makes differences in calf diarrhea rates by influencing gut microbial composition and interactions.

Background: Intensive ruminant production systems rely heavily on corn silage (CS) as a primary forage source; however, its resource-intensive cultivation and environmental constraints necessitate the development of sustainable alternatives. Methods: In a 90-day feeding trial, 24 growing heifers were assigned to diets in which CS was replaced by triticale silage (TS) at 0, 25, 50%, or 100% (DM basis). Growth performance, rumen fermentation, ruminal fatty acid (FA) profiles, and integrated rumen microbiome-metabolome interactions were evaluated. Results: A 25% substitution (TS25) as the optimal level, maintaining growth performance comparable to the control while achieving the lowest feed cost of gain. TS25 improved rumen fermentation (lower A: P and high total VFA), promoted more efficient nitrogen utilization (higher MCP with lower ammonia N), and enriched functionally relevant bacteria associated with fiber degradation and fermentation (e.g., Ruminococcus , Prevotella , and Rikenellaceae_RC9_gut_group ). Consistently, TS inclusion shifted ruminal lipid metabolism, increasing UFA proportions and elevating PUFA (TS25 and TS50 increased PUFA by 15.2 and 23.7% vs. control), alongside metabolomic signals indicating upregulation of linoleic acid metabolism and aromatic amino acid biosynthesis pathways. In contrast, TS substitution ≥50% reduced DMI and ADG, impairing feed utilization. Conclusion: Partial replacement of CS with TS at 25% provides a practical, data-supported strategy to improve economic efficiency while maintaining productivity and promoting favorable rumen microbial-metabolic features. This feeding approach may be applicable in water-limited or double-cropping regions, where TS can enhance forage system sustainability without compromising heifer growth.

Introduction: This study aimed to develop probiotics capable of efficiently utilizing soluble protein (SP) and to evaluate their effects on rumen fermentation and microbiota under different substrate protein structures. Methods: Cottonseed meal, corn flour, and wheat bran were fermented with seven single strains and combinations of probiotics. The selected compound probiotic, Candida tropicalis and Enterococcus faecalis , was then used to prepare substrates with three SP:insoluble protein (ISP) ratios (1:2, 1:2.5, and 1:3) for in vitro rumen fermentation. Fermentation parameters and the rumen microbial community were assessed. Results: C. tropicalis , Saccharomyces cerevisiae, and E. faecalis outperformed the other single strains in increasing substrate SP. The combination of C. tropicalis and E. faecalis significantly increased the substrate SP proportion. At an SP:ISP ratio of 1:2.5, total volatile fatty acids, acetate, propionate, and valerate were significantly increased. Crude protein degradation was significantly higher in the 1:2 and 1:2.5 groups than in the 1:3 group. The relative abundances of Streptococcus and Ruminobacter were significantly higher in the 1:2.5 group. Discussion: These in vitro findings provide preliminary evidence that optimizing the SP:ISP ratio in combination with compound probiotic supplementation may improve ruminal nitrogen utilization efficiency. Further in vivo validation is warranted.