Studies On Roles Of Dietary Daidzein In Laying Hens

Daidzein is isoflavonic phytoestrogen. It not only could help people resist cancer and oxidation, reduce the content of cholesterol, but could help animal improve immune function and breed performance, and daidzein have the advantage of lower toxicity. The experiment conducted with Hy-line brown laying hens to study the effect of diet supplemented daidzein on eggshell quality, bone metabolism, endocrine, production performance and immune function in laying hens. Those provide the academic and practical basis for the application of daidzein using in poultry production.144 sixty-week-old Hy-line brown laying hens were randomized into 4 treatments, with four replications per treatment. The control hens were raised basal diet consisting of a corn-soybean -mixed meal, and trials were supplemented with 10, 20 and 30 mg/kg daidzein. Egg laying rate and feed consumption were noted during the experiment; egg samples and serum samples were collected to determine at the finally of experiment. The results showed as follows: (1)Diet supplemented daidzein improved eggshell quality. Compared to control, eggshell thickness enhanced (P<0.01)in all trials supplemented daidzein. Eggshell weight was increased (P<0.05), and eggshell thickness and eggshell weight increased to the highest in the treatment of l0mg/kgDa; eggshell broken rate decreased to the lowest (P<0.05), eggshell thickness enhanced (P<0.01) with 30mg/kgDa. (2)Bone mineral density (BMD) and serum calcium were advanced, AKP activity was decreased in all trials supplemented with daidzein. Serum calcium increased by 23.16% (P<0.05) with 10mg/kg Da; BMD was the highest (P<0.05), AKP activity was the lowest (P<0.05) at the dose of 20mg/kg. Diet supplemented with 10~20mg/kg daidzein affected bone metabolism.(3)Diet supplemented daidzein affected endocrine of laying hens. The contents of T3, T4 and IGF-1 in difference trials supplemented with daidzein are higher than the control. The content of T3 was higher with more daidzein, but the difference is not significant (P>0.05); IGF-1 was the highest (P<0.05)with l0mg/kg Da; T4 wasincreased by 40.03% (P<0.01), and the change of E2was not significant(P>0.05).(4) Diet supplemented daidzein diet affected producing performance. Egg weight was the highest (P<0.05), and feed consumption and feed/egg ratio decreased (P<0.05) at the dose of 10 mg/kg; the egg laying rate fed diet containing 20mg/kg of daidzein markedly higher by 14.56%(P<0.01).144 fifty-week-old Hy-line brown laying hens were randomized into 4 treatments, with four replications per treatment. The control hens were raised basal diet consisting of a corn-soybean -mixed meal, and trials were supplemented with 10, 20 and 30 mg/kg daidzein. At the finally, serum samples were collected for further assessing of numbers of T lymphocyte and layer's ND-HI liters. Spleens were separated for counting immune apparatus index. Results showed that spleen index (P<0.05). ND-HI titers and ERFC (P>0.05) of laying hens improved with 20mg/kgDa; ND-HI titers were enhanced significantly (P<0.05). and spleen index and ERFC (P>0.05) heightened at the dose of 30mg/kg. So diet supplemented daidzein improved humoral immune function , and cell immune function was more higher with more supplement.