Yeast culture promotes albumen quality by improving magnum protein secretion and intestinal microbiota in aged laying hens

Abstract BACKGROUND The supplementation of yeast culture (YC) has the potential to enhance egg quality in laying hens. However, most studies focus on eggshell quality. This study aimed to investigate the effects of dietary YC supplementation on the production performance, albumen quality, protein synthesis or secretion of the magnum and the cecal microbiota content of laying hens. RESULTS The results showed that dietary YC supplementation increased albumen height and Haugh unit ( P ≤ 0.05). Besides, dietary 100 g kg −1 YC addition increased significantly the ridge width of the magnum and the relative expression of SEC23A in the magnum and decreased significantly the relative expression of OVOB in the magnum ( P ≤ 0.05). Furthermore, the abundances of Butyricicoccus , Alistipes and Flavonifractor were increased significantly by 100 g kg −1 YC supplementation ( P ≤ 0.05). The diet supplemented with 100 g kg −1 YC significantly increased the butyric acid and isobutyric acid of the cecum. CONCLUSION Dietary supplementation with YC improved protein secretion in the magnum and enhanced the beneficial cecal microbiota, thus improving the albumen quality of laying hens. © 2025 Society of Chemical Industry.