Wenjiao Li

Polysaccharides from edible fungi are increasingly recognized as bioactive macromolecules with potential relevance to animal nutrition, intestinal health, and stress resilience. Lyophyllum decastes polysaccharides (LDPs) have recently attracted attention because of their reported immunomodulatory, antioxidant, anti-inflammatory, microbiota-modulating, and intestinal barrier-related activities. Available studies indicate that LDPs are structurally heterogeneous preparations whose biological properties are influenced by raw material source, extraction method, purification level, molecular weight distribution, monosaccharide composition, glycosidic linkage pattern, branching architecture, and associated non-polysaccharide components. Evidence from in vitro assays and rodent models suggests that selected LDP preparations may interact with innate immune signaling pathways, regulate oxidative and inflammatory responses, resist complete upper gastrointestinal digestion, undergo microbial fermentation, promote short-chain fatty acid production, alter gut microbiota composition, and improve intestinal barrier-related indices. These properties provide a biologically plausible basis for poultry-oriented investigation, particularly in broilers and laying hens exposed to heat stress, enteric challenge, intestinal dysbiosis, oxidative burden, or antibiotic-reduced production systems. However, the current evidence base remains largely pre-translational. Most findings are derived from chemical assays, macrophage models, simulated digestion, fecal fermentation, or murine disease models rather than controlled poultry trials. Therefore, LDPs should not yet be regarded as established feed additives for poultry. This review summarizes current knowledge on the extraction, structural features, biological activities, safety considerations, and translational prospects of LDPs, with emphasis on poultry nutrition. Key research priorities include standardized preparation and reporting, structure–function mapping, endotoxin and contaminant control, chicken-relevant mechanistic validation, target-animal safety assessment, dose–response feeding trials, challenge models, and evaluation of feed-scale feasibility. Overall, LDPs represent promising candidate functional materials for poultry nutrition, but their practical application requires rigorous poultry-specific validation.