Abstract
The aim of this study was to investigate the effects of different probiotic fermented diets on production performance and intestinal health of laying hens. A total of 360 healthy 22-wk-age Jingfen No. 6 layers were randomly divided into 4 treatments: basal diet (CON); supplemented with 6% Clostridium butyricum fermented feed (CB); supplemented with 6% Lactobacillus crispatus fermented feed (LC); supplemented with 6% Lactobacillus salivarius fermented feed (LS). The experiment lasted for 8 wk. The results showed that the levels of crude fiber, β-glucan and pH of feed decreased significantly after fermentation (P < 0.05). Compared with CON group, the feed conversion ratio (FCR) was decreased significantly (P < 0.05), and albumen height and Haugh unit in LC group and LS group were increased significantly (P < 0.05). Fermented feed supplementation significantly improved villus height (VH) of the jejunum and the ratio of villus height to crypt depth (VH/CD) of the ileum (P < 0.05). Additionally, the VH and VH/CD of the duodenum were significantly increased in LS group (P < 0.05). Furthermore, the ACE and chao1 indexes in LS group were extremely significant higher than that in the other 3 groups (P < 0.05). In addition, compared with CON group, the abundance of Rikenellaceae and Methanobacteriaceae was significantly decreased at the family level in LC group and LS group (P < 0.05), while the abundance of Ruminocaceae was significantly higher (P < 0.05). Collectively, feeding Lactobacillus salivarius and Lactobacillus crispatus fermented feed improved the FCR, albumen height and Haugh unit of laying hens, and Lactobacillus salivarius fermented feed supplementation could improve intestinal health by ameliorating intestinal morphology, altering microbial composition and enhancing microbial community richness.