Abstract
This study determined the effects of coated sodium butyrate (CSB) on production performance, egg quality, nutrient digestibility, and intestinal health of laying hens. We divided a total of 800 Lohmann laying hens, aged 51 wk, into 4 treatment groups: 0 (CON), 300 (CSB1), 500 (CSB2), and 800 (CSB3) mg/kg of CSB. Each group comprised 20 birds, with 10 replicates set. A 12-wk monitoring process was conducted for each laying hen. Compared to CON, dietary supplementation of CSB did not affect the average daily feed intake or the egg weight. The CSB3 group demonstrated a linear increase in the production performance (P < 0.05), with decreased feed conversion ratio (P < 0.05). CSB2 and CSB3 exhibited markedly elevated egg mass (P < 0.05). The CSB supplementation markedly enhanced the yolk color (P < 0.05). CSB1 improved the digestibility of dry matter (P = 0.029). No significant differences were observed among dietary treatments in the duodenal morphology (P > 0.05). The three dosages of CSB reduced the crypt depth (P < 0.05) in the jejunum, whereas CSB3 exhibited an increase in the villus height (VH; P = 0.048). The CSB3 group showed a markedly elevated ileal VH (P = 0.011). CSB supplementation significantly increased the butyric acid content in the cecum (P = 0.009). The hens fed on the 800 mg/kg CSB diet showed a significant increase (P = 0.029) in butyric acid content in the ileum. The CSB3 group showed an elevation in microbial diversity (P < 0.05). Additionally, at the phylum level, the CSB3 increased the enrichment of Bacteroidetes, the CSB2 increased Firmicutes, and the abundance of Deferribacteres was increased in CSB2 and CSB3 groups (P < 0.05). An enrichment of Muribaculaceae (family) was observed in the CSB3 group. In conclusion, dietary supplementation of CSB improved production, yolk color, intestinal morphology, butyrate content, and microbial composition in laying hens.