Nutritional Intervention: Impacts on Gut Microbiome, Health, and Productivity of Laying Hens
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Abstract
Modulating the gut microbiome is critical for maintaining the health and productivity of laying hens. Nutritional interventions are essential for preserving gut integrity under the pressures of high egg production and alternative housing systems. The present study aimed to provide a comprehensive synthesis of current knowledge on the relationship between nutritional strategies and gut microbiome modulation and productivity in laying hens. A systematic literature search of PubMed, Scopus, and ScienceDirect (2015-2026) retrieved 108 studies that met the eligibility criteria for qualitative analysis. The inclusion of probiotics, prebiotics, organic acids, exogenous enzymes, vitamins, minerals, and amino acids in laying hen diets was associated with improved microbial balance, intestinal function, immune status, and nutrient utilization, resulting in greater egg production and egg quality. These nutritional approaches provided sustainable alternatives to antibiotic growth promoters, supporting resilient egg production systems by improving gut health and maintaining productive performance in laying hens. Productive performance, short‑chain fatty acid production, and reduced pathogenic colonization in laying hens were all positively influenced by nutritional interventions that effectively modulate the gut microbiome.
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