Effects of Green Tea Powder Feed Supplement on Performance of Hens in the Late Stage of Laying

The effects of green tea powder on the levels of alpha-tocopherol in egg yolk, egg production and egg quality of laying hens were examined. Twenty 84-week-old laying hens were divided into 4 dietary groups of 5 hens each in the late stages of laying. Four levels of green tea powder (0% = control diet, 1%, 5% and 10%) were fed to the hens for 3 weeks. At the end of 3 weeks, all experimental diets were switched to the control diet (0% green tea powder) for 3 weeks. The first group was fed the controlled diet throughout the experimental period. The egg weight, egg mass and feed intake were the highest for the 0% and 1% green tea powder diets and the lowest for the 5% and 10% diets (P < 0.05). The rate of egg production and the intake of feed decreased significantly with an increase in the intake of green tea powder (P < 0.05). The weights of the hens who received up to 5% green tea powder in their diets decreased. However, the gain in the hens' weight was not influenced by the intake of 1% green tea powder diet. There were no significant differences in the yolk color fan score for the 4 treatment diets. The egg shell strength decreased with increasing green tea powder intake, while the alpha-tocopherol content of egg yolk of the hens fed the experimental diet increased with increasing green tea powder intake. The fatty acid composition of yolk was not affected by the diet. The results suggested that the transfer of alpha-tocopherol from dietary green tea powder to egg yolk was sensitive to the alpha-tocopherol intake and that green tea supplementation would support adequate egg production and egg weight when used up to a level of 1% in the diets of laying hens.