Curcumin improves the egg quality, antioxidant activity, and intestinal microbiota of quails during the late laying period

This study aimed to investigate the effects of dietary curcumin supplementation on laying performance, egg quality, egg metabolites, lipid metabolism, antioxidant activity, and intestinal microbial composition of quails in the late laying period. A total of 960 late-laying quails (240-day-old) were randomly divided into 4 groups of 6 replicates each (n = 40/replicate). The experimental diets of the 4 groups consisted of basal diets supplemented with 0, 50, 100, and 200 mg/kg curcumin, respectively. The feeding experiment lasted for 8 wk. The results showed that 200 mg/kg curcumin supplementation decreased mortality and increased eggshell thickness and strength compared with the 0 mg/kg curcumin supplementation during wk 5 to 8. In addition, dietary supplementation of curcumin promoted lipid metabolism, enhanced antioxidant activity, and modified intestinal microbiota structure. In conclusion, dietary supplemented with 200 mg/kg curcumin significantly improved the egg quality of quails in the late laying period, primarily by improving lipid metabolism and selectively regulating the intestinal microbial community.