绝食对九龙牦牛体重、血清激素和生化指标的影响

Effects of Starvation on Body Weight,Serum Hormone and Biochemical Indexes of Jiulong Yaks

本试验旨在研究冷季绝食应激时九龙牦牛体重、血清激素和生化指标的变化。选择8头健康无病、生长发育良好的2岁九龙牦牛8头,体重为(90.75±8.66)kg,按体重相近的原则随机分为对照组和绝食组,每组4个重复,每个重复1头牛。对照组正常饲喂,绝食组牦牛做断料处理。试验期7 d。分别在试验开始后的第1、3、5、7天称重和通过颈静脉采血。结果表明:绝食7 d后牦牛的体重显著降低(P<0.05),血清中葡萄糖、胰岛素含量显著下降(P<0.05),血清非酯化脂肪酸、甘油三酯、脂联素和胰高血糖素含量显著升高(P<0.05),血清中糖异生前体物质丙酸、乳酸的含量显著降低(P<0.05),而血清中来源于体储降解的甘油、β-羟丁酸的含量显著升高(P<0.05),血清中糖异生关键酶丙酮酸羧化酶、果糖1,6二磷酸酶、磷酸烯醇式丙酮酸羧激酶、葡萄糖六磷酸酶的活性均显著升高(P<0.05)。结果提示,绝食7 d后牦牛开始大量动用体储,提高糖异生代谢过程,维持机体代谢的正常需要,保证血清葡萄糖含量的稳定以维持生命。

This experiment was conducted to investigate the changes of body weight, serum hormone and bio- chemical indexes of Jiulong yaks under starvation stress during cold season. Eight 2-year-old Jiulong yaks, which were healthy, in good condition and consistent in body weight [ （90.75_＋8.66） kg~, were selected and randomly divided into control group and starvation group, each group had 4 replicates with 1 yak per replicate. Yaks in control group were normally fed, and those in starvation group were suffered from starvation. The ex- periment lasted for 7 d. On days 1, 3, 5 and 7, body weight was measure, and blood sample was collected through jugular vein. The results showed as follows ： after 7 d starvation, body weight of yaks was significantly decreased （P〈0.05）, serum contents of glucose and insulin were significantly decreased （P〈0.05） , serum contents of non-esterified fatty acid, triglyceride, adiponectin and glucagon were significantly increased （P〈 0.05）, serum contents of propionic acid and lactic acid as gluconeogenesis substances were significantly decreased （P〈0.05） , serum contents of glycerine and [3-hydroxybutyric acid from body decompose were significantly increased （P〈0.05）, and serum activities of pyruvate carboxylase, fructose-l,6-bisphosphatase, phos-phoenolpyruvate carboxykinase and glucose-6-phosphatase as key enzymes of gluconeogenesis were significant- ly increased （P〈0.05）. The results indicate that yaks use the energy stored in the body after starvation, evaluate gluconeogenesis to satisfy normal requirements, and maintain serum glucose content stability and vital activities.