雌二醇对肉用仔鸡脂肪代谢的影响

EFFECT OF ESTRADIOL ON LIPID METABOLISM IN BROILER CHICKENS

本实验选用马歇尔雄性肉用仔鸡,探讨雌二醇对肉用仔鸡脂肪代谢的影响。 5～10周龄仔鸡血清β-脂肪蛋白含量随周龄明显上升,并与体重呈强正相关。给鸡外源雌二醇2mg/只,一次性肌肉注射后5小时,β-脂蛋白含量明显增加,26小时达到高峰,直到98小时回到对照组水平。血清β-脂蛋白含量和肝脏NADP-苹果酸脱氢酶活性,因外源雌二醇剂量的加大而升高。在用外源雌二醇多次处理时,血清β-脂蛋白长期保持在高水平;于停止注射后第6天回到对照组水平;停止注射后第9天,实验组体重、肝重、腹脂重、肝脏总脂含量、肌肉中总脂含量、肝脏NADP-苹果酸脱氢酶活性均显著高于对照组。 还发现未经外源雌二醇处理的6～10周龄雄性肉用仔鸡血清雌二醇水平(139.06～229.10pg/ml)显著高于 2～5周龄的水平,近似于性成熟产蛋母鸡的水平。2～10周龄血清雌二醇与β-脂蛋白含量呈强正相关。结果说明:雌二醇在肉用仔鸡6～10周龄期间,对脂肪代谢有很重要的调节作用。

Present experiment was carried out to explore the effect of estradiol on lipid metabolism in broiler chickens. 70 Marshall male broiler chickens were used. In the growing period ( 5 ~10 weeks old ) , concentration of serum β-lipoprotein increased significantly, and there was a significant positive correlation between serum β-lipoprotein and body weight. When broiler chickens were treated with a single intramuscular injection of estradiol( 2mg/each ) , concentration of serum β-lipoprotein significantly increased at 5h.after treatment and reached a peak value at 26h.,which was 6.3 times higher than that of control and returned to level of the control at 98 hour. Concentration of serum β-lipoprotein and specific activity of NADP-malate dehydrogenase in liver increased significantly when the dose of exogenous estradiol increased. Multi- injection of estradiol significantly increased body weight, abdominal fat weight, liver weight, lipid concentration in the liver and the muscle, and the specific activity of NADP-malate dehydrogenase in liver on the 9th day after the last injection. Serum β-lipoprotein kept a high concentration and returned to the control's level on the 6th day after the last injection. Concentration of serum estradiol of male broiler chickens from 6 to 10 weeks old ( 138.06~229.10 pg/ml ) were higher than that from 2 to 5 weeks old, and it was approximately equal to that of mature laying hen. There was a significantly positive correlation between serum estradiol and β-lipoprotein from 2 to 10 weeks old. These results indicate that estradiol does play an important role in lipid metabolism in broiler chickens.