Effects of Different Levels of Green Tea Powder on Performance, Antioxidant Activity, Egg Mass, Quality, and Cecal Microflora of Chickens.

Simple Summary: The addition of alternative feed sources such as Green Tea Powder to the feed of poultry, especially laying hens, has attracted attention due to its potential benefits. Therefore, the purpose of this study—with the addition of Green Tea Powder to the diet of laying hens—is, on the one hand, to explore the beneficial effects of Green Tea Powder on the production performance and physical function of laying hens and, on the other hand, to explore the utilization of Green Tea Powder and improve the utilization rate of biological resources. In conclusion, dietary supplementation of Green Tea Powder during the laying period can reduce the serum yolk weight of laying hens. The serum levels of immunoglobulin A and immunoglobulin M were increased, and the serum levels of malondialdehyde were decreased. Egg shell strength and shell thickness decreased, and egg yolk color deepened. Additionally, the percentage of amino acids in the eggs increased. It is beneficial to the health of laying hens to increase the diversity of intestinal flora and improve the structure of cecum flora. This study investigated the effects of Green Tea Powder supplementation on the performance and egg quality of laying hens and ultimately guided the development of more effective and scientific animal feeding strategies. This study was conducted to investigate the effects of different levels of Green Tea Powder on the performance, egg quality, serum immune and antioxidant indices, and cecal microflora of 300-day-old Chishui black-bone chickens during the peak laying period. A total of 360 Chishui black-bone chickens were selected as the experimental animals. They were randomly allocated into four groups: the control group (CON), trial group I (T1), trial group II (T2), and trial group III (T3), each group with six replicates and 15 hens in each replicate. The control group was fed a basal diet, and the experimental groups were fed a basal diet supplemented with 0.8%, 1.6%, and 2.4% Green Tea Powder, respectively. The accommodation period was 14 d, and the experimental period was 60 d. The statistical software SPSS was used to perform a one-way analysis of variance (ANOVA) on the experimental data, and Duncan's method was used to perform multiple comparisons among groups. The results showed the following: compared with those of the control group, the average daily gain of the laying hens significantly decreased in the 1.6% Green Tea Powder group (p < 0.05); adding Green Tea Powder significantly reduced the content of malondialdehyde in the serum (p < 0.05), and the addition of 0.8% tea leaves significantly increased the immunoglobulin M and immunoglobulin A contents (p < 0.05); the egg yolk weight, eggshell thickness, eggshell strength, and yolk color of the laying hens significantly decreased in the 1.6% Green Tea Powder group (p < 0.05), and the addition of Green Tea Powder at the level of 2.4% significantly increased the percentage of umami, essential, and total amino acids (p < 0.05); and the structure of intestinal microorganisms was improved, and the abundance of Bacteroidetes and Bacteroidaceae significantly increased, while the abundance of Firmicutes and Lachnospiraceae significantly decreased (p < 0.05). [ABSTRACT FROM AUTHOR]