ABSTRACT: The intestinal mucosa is the main organ that exerts nutrient absorption, which will further influence laying performance and egg nutrition in hens. Previously, we have screened out three strains of Lactobacillus (L. sa., L. ag. and L. av.) from a native chicken breed in China. However, the optimal regulation of Lactobacillus combination on poultry products needs to be verified. In this study, a total of 120 HyLine hens (n = 30) at the period of laying peak were randomly divided into four groups: (1) control, (2) L. sa. + L. ag., (3) L. sa. + L. av. and (4) L. ag. + L. av. groups, which were fed with corresponding Lactobacillus (10e8 CFUs/hen/day) for 30 consecutive days. Compared with the control group, feeding of L. sa. + L. ag. could improve the laying rate, egg weight, especially for higher amino acids level in albumen. The mechanism study showed that, in the intestine lumen, feeding of L. sa. + L.ag. could up-regulate the Lactobacillus abundance and down-regulate the Escherichia coli abundance. Meanwhile, the tryptophan metabolism pathway was up-regulated, the primary bile acid biosynthesis pathway was down-regulated. In the crypt, up-regulated genes involved the oxidative phosphorylation pathway and the ROS level were appeared in L. sa. + L.ag. feeding group. Our study further proved that the amount of Paneth cells and the mRNA abundance of Wnt3a and Dll1 in the crypt were up-regulated upon L. sa. + L. ag. feeding. Correspondingly, the mRNA abundance of Lgr5, CCND1 and CDK2 in the crypt were enhanced upon L. sa. + L. ag. feeding. In conclusion, co-feeding of L. sa. and L. ag. in hens could improve the gut microflora and altered the microflora metabolism profile in the intestine. Further, promote the crypt’s local energy metabolism and enhancing ROS level in the crypt, thereby enhance the activity of Paneth cell and regulate the activity of ISCs. Ultimately, the intestinal mucosal renewal and the laying performance were improved.
