Effects of citrus extract supplementation on laying performance and egg quality in layers.

The aim of this study is to explore the effects of citrus extracts (CEs) supplement in diet or in drinking water on laying performance and egg quality of layers in late laying period. Ninety 68-week-old Lohmann layers were employed and random divided into 5 treatment groups: basal diet (C), supplemented with 0.5 g CEs per kg basal diet (P-0.5), supplemented with 1 g CEs per kg basal diet (P-1), supplemented with 0.5 mL CEs per L drinking water (W-0.5), and supplemented with 1 mL CEs per L drinking water (W-1). Each group had 3 replicates with 18 layers. The egg quality was measured on the day-1,7, 21, 35 and 49 in 7-week trial period, and the egg weight, laying rate and feed consumption were recorded at the same time. The results showed that group P-1 had a higher weight of eggshell than control (P = 0.027) and group W-0.5 (P = 0.028). The egg weight in group P-0.5 was significantly higher than control (P = 0.027) while the group W-0.5 was lowest (P = 0.0001). The egg production rate in group P-1 was significantly higher than control (P = 0.0051) and group W-1 (P = 0.036). [ABSTRACT FROM AUTHOR]