不同脂肪源日粮对大鼠生长及餐后糖脂代谢的影响

Effects of Dietary Fat Sources on Growth and Postprandial Lipid and Glucose Metabolism in Rats

通过饲喂不同脂肪源的等营养水平日粮,研究不同种类脂肪对生长期SD大鼠生长及餐后糖脂代谢的影响。试验采用单因子试验设计,将72只体重为60～90 g的SD大鼠随机分为6组,每组12个重复,每个重复1只大鼠。6组大鼠分别饲喂无脂纯合型日粮、普通型日粮和10%玉米油、牛脂、棕榈油及椰子油纯合型日粮。试验分为2个阶段,共28 d。每周称大鼠个体重,第15天及第29天,测糖脂代谢相关指标。结果表明,试验第8天,添加脂肪的纯合日粮组大鼠体重均高于无脂组,玉米油组大鼠体重显著高于牛脂组、棕榈油组及椰子油组(P<0.05);试验第8天、第15天、第22天和第29天,玉米油组的体重显著或极显著高于无脂组(P<0.05或P<0.01)。试验第15天,添加脂肪的纯合日粮组大鼠餐后血脂水平均高于无脂组,且牛脂组及棕榈油组的甘油三酯、总胆固醇及游离脂肪酸均极显著高于无脂组(P<0.01)。试验第15天和第29天,普通日粮及添加脂肪的纯合日粮组血糖水平均高于无脂组,但差异不显著(P>0.05);玉米油组和椰子油组胰岛素和胰高血糖素水平均显著极显著低于牛脂组及棕榈油组(P<0.05或P<0.01)。结果显示,玉米油的促生长效果优于椰子油、牛脂及棕榈油,且玉米油和椰子油不会升高餐后血脂及血糖水平。

The experiment was conducted to evaluate the effects of dietary fat sources on growth and postprandial lipid and glucose metabolism in growing Sprsngue dawley （SD） rats. By single factorial designed experiment, seventy-two SD rats with body weight of 60--90 g were divided into 6 groups with per group containing 12 replicates of 1 rat. The 6 groups were common diet group supplemented with soybean oil, fat-free purified diet group or purified diet groups supplemented with corn oil, beef tallow, palm oil and coconut oil, respectively. The experiment had two stages and lasted for 28 d. Body weights of rats were weighed every week, and on day 15 and day 29, indices about lipid and glucose metabolism were determined. The results showed that, on day 8 of experiment, body weights of rats in purified diet groups supplemented with fat were all higher than those in fat-free purified diet group, and body weights of rats in corn oil group were significantly higher than those in beef tallow group, palm oil group and coconut oil group（P〈0.05） ; on day 8, day 15, day 22 and day 29 of experi- ment, body weights of rats in corn oil group were significantly higher than those in fat-free purified diet group （P〈0.01 or P〈0. 05）. On day 15 of experiment, postprandial lipid levels of rats in purified diet groups adding fat were all higher than those in fat-free purified diet group, and triglyceride, total cholesterol and free fatty acids in beef tallow group and palm oil group were significantly higher than those in fat-free purified diet group （P〈0. 01）. On day 15 and day 29, blood glucose levels in common diet group and purified diet groups adding fat were higher than those in fat-free purified diet group, but the differences were not significant （P〈0. 05） ; insulin levels in corn oil group and coconut oil group were significantly lower than those in beef tallow group and palm oil group （P〈0. 01 or P〈0. 05）. In conclusion, compared with beef tallow, palm oil and coconut oil, corn oil had better effects on promoting growth, and corn oil and coconut oil did not increase the postprandial lipid and glucose concentrations. [Chinese Journal of Animal Nutrition, 2009,21（5） ：769-776 ]