Lactobacillus salivarius and Lactobacillus agilis feeding regulates intestinal stem cells activity by modulating crypt niche in hens.

Previously, we found that Lactobacillus salivarius, Lactobacillus agilis, and Lactobacillus aviarius were associated with excellent egg nutrition in native chicken. Next, the optimal Lactobacillus combination is worth studying. Here, a total of 120 HyLine hens (30 hens per group contained 3 replicate cells, 10 hens/cell) in the laying peak period were randomly divided into (1) control, (2) L. salivarius + L. agilis, (3) L. salivarius + L. aviarius, and (4) L. agilis + L. aviarius groups, fed with diet only or with corresponding Lactobacilli (108 colony-forming units/hen/day) for 30 days. As a result, L. salivarius + L. agilis feeding could (1) improve egg-laying rate, egg weight, and albumen's amino acid levels; (2) increase Lactobacillus abundance, decrease Escherichia coli abundance, upregulate the tryptophan metabolism pathway-related molecules, and downregulate the primary bile acid biosynthesis pathway-related molecules in intestinal contents; and (3) upregulate oxidative-phosphorylation pathway-related genes, reactive oxygen species levels, and mRNA abundance of Wnt3a, Dll1, Lgr5, CCDN1, and CDK2 in the crypt. Collectively, L. salivarius + L. agilis feeding in hens could improve intestinal microflora and metabolism profile, promote crypt's local energy metabolism and reactive oxygen species levels, and thus enhance Paneth cells and intestinal stem cells activity.Key points• Lactobacilli co-feeding could improve laying performance and egg nutrition.• Lactobacilli co-feeding could improve intestinal microflora and metabolism profile.• Lactobacilli co-feeding could enhance Paneth cells and intestinal stem cells activity.