Effects of creatine pyruvate on lipid and protein metabolism in broiler chickens | 丙酮酸肌酸对肉鸡脂肪代谢和蛋白质代谢的影响

Chinese. 摘　　要：300羽1日龄雄性AA肉鸡随机分为4组,每组3个重复,每个重复25羽。分别于基础日粮中添加质量分数为1%、5%和10%丙酮酸肌酸（CrPyr）,以不添加CrPyr为对照,饲喂至42日龄时各组每个重复分别随机宰杀4只,采集血样、肝脏、腹脂、左侧胸肌和腿肌,测定血清葡萄糖（BG）、甘油三酯（TG）、总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）、肌酸激酶（CK）、尿酸（UA）、三碘甲腺原氨酸（T3）、甲状腺素（T4）、游离三碘甲腺原氨酸（FT3）、游离甲状腺素（FT4）、胰高血糖素、胰岛素和瘦素含量,以及肌肉核酸和蛋白质含量。结果表明：与对照组相比,CrPyr显著降低肉鸡腹脂率及肝脏和血清中TG、LDL-C、UA含量,但增加血清FT3含量;CrPyr明显提高胸肌率、腿肌蛋白质含量及RNA/DNA值;同时CrPyr还提高了肌肉胰岛素样生长因子Ⅰ（IGF-Ⅰ）和生肌调节因子的mRNA转录水平。提示：CrPyr可通过提高肉鸡体内脂类分解代谢相关酶活性及激素水平,对脂肪代谢起调节作用;同时通过促进蛋白质的沉积,提高肌肉蛋白质含量,促进肌肉生长。

English. Three hundreds 1 day-old male AA broilers were randomly divided into four groups,and each group included three replicates with 25 broilers.Creatine pyruvate（CrPyr）was not added in the basal feed（control group）.The low,middle and high CrPyr treated groups were fed with the basal feed with the supplementation of 1%,5% and 10% from 1 to 42 day-old,respectively.Four broiler chickens per replicate from each treatment were chosen randomly and slaughtered to collect specimens of blood,liver,abdominal fat,left breast and leg muscle samples at 42 day-old.The content of blood glucose（BG）,triglycerides（TG）,total cholesterol（TC）,high density lipoprotein-cholesterol（HDL-C）,low density lipoprotein-cholesterol（LDL-C）,creatine kinease（CK）,uric acid（UA）,triiodothyronine（T3）,thyroxin（T4）,free triiodothyronine（FT3）,free thyroxin（FT4）,glucagon,insulin,leptin and the content of nucleic acid and protein in muscle were detected.The results showed that CrPyr significantly decreased the percentage of abdominal fat weight and the concentrations of TG,LDL-C and UA in liver and serum,but it obviously increased serum FT3 value,and unchanged BG and TC levels.The relative pectoral muscle weight,the protein content of leg muscle and the RNA/DNA ratio of CrPyr-administered groups were significantly higher than those of control group.CrPyr also elevated the expressions of IGF-Ⅰ and myogenin mRNA in muscle.The findings suggest that CrPyr regulates lipid metabolism of broilers by enhancing the enzyme activity and hormone levels related to lipolysis.Also CrPyr may improve the muscle growth by elevating the synthesis of protein in broilers.