本试验旨在研究饲粮中添加红三叶异黄酮对肉鸡血液几种内源性激素水平的影响。选取1日龄雄性爱拔益加肉仔鸡240羽,随机分为4组(每组4个重复,每个重复15只),分别饲喂在基础饲粮中添加0(对照组)、10(试验Ⅰ组)、20(试验Ⅱ组)、30 mg/kg(试验Ⅲ组)红三叶异黄酮的试验饲粮。试验持续7周。结果表明:试验Ⅰ组和试验Ⅱ组的平均日增重显著或极显著高于对照组和试验Ⅲ组(P<0.05或P<0.01)。各试验组料重比均低于对照组,但差异不显著(P>0.05)。血清生长激素(GH)水平,试验Ⅱ组在21、35和49日龄均显著或极显著高于对照组(P<0.05或P<0.01),试验Ⅰ组在49日龄、试验Ⅲ组在21日龄显著或极显著高于对照组(P<0.05或P<0.01);血清类胰岛素生长因子Ⅰ(IGF-Ⅰ)水平,各试验组在21日龄均显著高于对照组(P<0.05),试验Ⅱ组在49日龄显著高于对照组和其他试验组(P<0.05);血清三碘甲腺原氨酸(T3)水平,试验Ⅰ组在35和49日龄、试验Ⅱ组在49日龄均显著或极显著高于对照组(P<0.05或P<0.01);血清四碘甲腺原氨酸(T4)水平,试验Ⅰ组和试验Ⅲ组在35日龄显著低于对照组(P<0.05);血清T3/T4,各试验组在21、35和49日龄均高于对照组,并且在35和49日龄试验Ⅰ组与对照组达到显著水平(P<0.05);血清睾酮(TESTO)水平,各组在21、35和49日龄均无显著差异(P>0.05)。由此得出,红三叶异黄酮可通过调节体内GH、IGF-Ⅰ、T3和T4水平来影响肉鸡的生长性能,饲粮中添加20 mg/kg时促生长效果较好。

The aim of this study was to observe the effects of red clover (Trifolium pretense) isoflavones on several blood endogenous hormone levels of broilers. Two hundreds and forty 1-day-old AA broilers were randomly divided into 4 groups with 4 replicates per group and 15 broilers per replicate. The broilers in the 4 groups were fed basal diet supplemented with 0 (control group), 10 (experimental groupⅠ), 20 (experimental group Ⅱ) and 30 mg/kg (experimental group Ⅲ) red clover isoflavones, respectively. The whole experiment period was 7 weeks. The results showed as follows: the daily weight gain of broilers in the experimental groups Ⅰand Ⅱ was significantly higher than that in the control group and experimental group Ⅲ (P<0.05 or P<0.01). Feed/gain in the experimental groups was all lower than that in the control group, but had no significant difference (P<0.05). As for serum growth hormone (GH) level, the experimental group Ⅱ was significantly higher than the control group at 21, 35 and 49 days of age (P<0.05 or P<0.01); the experimental group Ⅰ at 49 days of age and experimental group Ⅲ at 21 days of age was higher than the control group (P<0.05 or P<0.01). Serum insulin-like growth factor-Ⅰ (IGF-Ⅰ) level in the experimental groups was all higher than that in the control group at 21 days of age (P<0.05), and that in the experimental group Ⅱ was significantly higher than that in the control group and other experimental groups at 49 days of age (P<0.05). Serum triiodothyronine (T3) level in the experimental group Ⅰ at 35 and 49 days of age and experimental group Ⅱ at 49 days of age was higher than that in the control group (P<0.05 or P<0.01), and serum thyroxine (T4) level in the experimental groups Ⅰ and Ⅲ at 35 days of age was lower than that in the control group (P<0.05). Serum T3/T4 in experimental groups was all higher than that in the control group at 21, 35 and 49 days of age, and experimental group Ⅰ had significant difference at 35 and 49 days of age (P<0.05). Red clover isoflavones had no significant effect on serum testosterone (TESTO) level of broilers (P>0.05). In conclusion, supplementation of red clover isoflavones can improve growth performance by regulating the levels of GH, IGF-Ⅰ,T3 and T4 in broilers, and the supplementation of 20 mg/kg has the better effect.