Effect of mannan-oligosaccharide prebiotic on performance, intestine ileum microflora, immune traits and ileum nutrient digestibility in laying hens fed diets with different crude protein levels

This study was carried out toinvestigate the effect ofmannan-oligosaccharide prebioticonperformance,egg quality, immune response, intestine ileum microflora and nutrient digestibility in laying hens fed various levels of crude protein. A total of 150 Hy-Line W-36 layinghens were assigned to a 2×3 factorial arrangement of treatments. Experimental diets consisted of 3 levels of crude protein (recommended level for strain, 90 and 95% of recommended level) and 2 levels of mannan-oligosaccharides (0 and 0.1% of diet). Reduction of crude protein to 10% of basal diet resulted in decrease of egg weight, egg production, egg mass and feed conversion ratio (P