The differences in the effects of supplementing lycopene or astaxanthin (from Pichia pastoris) on laying hens and eggs.

Carotenoids have strong antioxidant properties, widely used in food, cosmetics, and culture. In this study, we evaluated the impacts of lycopene rich P.pastoris (LRPP) and astaxanthin rich P.pastoris (ARPP) dietary supplementation on hens production performance, health status, and the eggs quality. The experiment involved the mount of two thousand two hundred and sixty-eight laying hens, all hens randomly divided into three groups (control group, LRPP group, ARPP group), each group with six replicates. The results showed LRPP or ARPP added could significantly increase egg production (P < 0.001). The yolk color and Haugh unit in LRPP and ARPP group were significantly improved (P < 0.001), but the eggshell thickness (mm) and eggshell strength (kg/cm) had no significantly change. By detecting the carotenoid content of egg yolk, it could be found ARPP had a significant effect on the accumulation of lutein in yolk (P < 0.001). And the ratio of unsaturated to saturated fatty acids in eggs was increased. Further, the level of superoxide dismutase (SOD) in serum was improved, ARPP had a more significant effect on the level of SOD and malondialdehyde (MDA). Additionally, ARPP increased the level of immunoglobulin G (IgG) and immunoglobulin A (IgA) (P < 0.05). Moreover, ARPP adding significantly increased the level of Estradiol 2 (E2) (P < 0.05) and Follicle-Stimulating Hormone (FSH) (P < 0.001). In conclusion, ARPP had a more significant benefits for both hens and eggs, the present data lay a foundation for further exploring the application of lycopene and astaxanthin in laying hens.