Dietary supplementation Eucommia ulmoides extract at high content served as a feed additive in the hens industry

Abstract

Since numerous natural components in Eucommia ulmoides belong to phytoestrogen, its effect on hens production deserve more attention. To investigate the potential of E. ulmoides extract used as a feed additive, laying performance, egg quality, yolk cholesterol, yolk fatty acids, yolk fatty, yolk volatile components, albumen amino acids, plasma biochemical parameters, intestinal histology, and gut microbiota of hens (n = 120) were determined between basal diet (A) and dietary supplementation low (B), middle (C), and high (D) level E. ulmoides extract for 11 wk. When compared to A group, 2 percentage points elevation in laying rate was observed of D group. Significant up-regulation of immunoglobulin indexes and down-regulation of lipid related indexes in D group were also found if comparison with A group, suggesting that supplementation E. ulmoides extract at a relative high content benefited in immunity enhancing and blood-fat depressing. Meanwhile, obvious variation in albumen amino acids and yolk volatile compounds were inspected as dietary supplementation E. ulmoides extract, especially in D group, implied that the flavor of egg would change under high-level E. ulmoides extract treatment. Besides, villus height and villus height to crypt depth ratio of duodenum, jejunum, and ileum in D group were also significantly higher than that of in A group, indicating high-level E. ulmoides extract contributed to nutrient adsorption via intestinal histology changing. Moreover, the richness, diversity, and composition of gut microbiota in D group also significantly altered with a comparison of A group. These variation caused gut microbiota in D group major enriched in the KEGG pathway of insulin signing pathway, systemic lupus erythematosus, and bacterial invasion of epithelial cells, which were conducive to egg production elevation via facilitating nutrient adsorption, inflammation relieving, blood lipid amelioration, and insulin resistance alleviation. These results indicated that dietary supplementation E. ulmoides extract at high content could serve as a feed additive in the hens industry.

Keywords: E. ulmoides extract; body health; gut microbiota; laying hens; production performance.

Figure 1

(A) The HS-GC-IMS results of yolk volatile components. (B) and (C) The PCA and OPLS-DA analysis of yolk volatile components of the 4 tested groups, respectively.

Figure 2

Effects of E. ulmoides extract on lipid related indexes in yolk and plasma. Different small letters indicated significant differences at P < 0.05 level of Tukey test under different treatments.

Figure 3

Effects of E. ulmoides extract on plasma immunoglobulin indexes. Different small letters indicated significant differences at P < 0.05 level of Tukey test under different treatments.

Figure 4

Effect of E. ulmoides extract on intestinal morphology. (A–D) Representative photomicrographs (5x) of villus in the duodenum, jejunum, and ileum of the 4 tested groups. (E) Villus height, crypt depth, and villus height to crypt depth ratio of duodenum, jejunum, and ileum in the 4 tested groups. Different small letters indicated significant differences at P < 0.05 level of Tukey test under different treatments.

Figure 5

Overall structure and composition of microbiota in cecum digesta of the 4 tested groups. (A–D) Shannon, Observed species, Chao 1, and Simpson indexes of the gut microbiota, respectively. (E) Unweighted Unifrac PCoA estimates for the gut microbiota. (F, G) The relative abundance of bacterial at phyla and genus levels, respectively. * P < 0.05, ** P < 0.01 compared to A group.

Figure 6

LEFSe analysis and bacterial phenotype prediction result of microbiota composition in cecum digesta of the 4 tested groups. (A) Gut microbiota difference at the genus level among the 4 tested groups based on LDA score (log > 2); (B–D) The relative abundance of gram-positive, gram-negative, and pathogenic potential, respectively. Different small letters indicated significant differences at P < 0.05 level of Tukey test under different treatments.

Figure 7

Heat map of significant enrichment KEGG pathway of the 4 tested groups.