【摘要】 本研究旨在探讨高浓度硫酸锌对仔猪肝脏脂肪代谢的影响。试验选用120头平均始重为(26.66±2.45)kg的"杜×长×大"三元杂交仔猪,随机分成4组(对照组、试验组Ⅰ、试验组Ⅱ和试验组Ⅲ),每组3个重复,每个重复10头猪,分别饲喂添加60、300、1000和3000mg/kg锌的基础饲粮。预试期7d,正试期16d。结果表明,与对照组相比,1)各试验组血清总甘油三酯和低密度脂蛋白胆固醇含量均显著提高(P<0.05);2)试验组Ⅲ血清总胆固醇、C18?1脂肪酸含量显著升高(P<0.05),肝脏C18?0、C18?2脂肪酸含量显著降低(P<0.05),而C16?0脂肪酸含量无显著变化(P>0.05);3)试验组Ⅱ和试验组Ⅲ肝脏硬脂酰辅酶A去饱和酶1(SCD1)mRNA水平、血浆瘦素和胰岛素含量都显著升高(P<0.05)。随着锌浓度的升高,血浆四碘甲状腺原氨酸(T4)含量显著降低(P<0.05),三碘甲状腺素原氨酸(T3)和胰高血糖素含量有上升趋势,但差异不显著(P>0.05)。由此可知,饲粮中添加1000和3000mg/kg锌上调了仔猪肝脏SCD1转录水平,促进了机体饱和脂肪酸(C18?0)的去饱和化,增加了机体甘油三酯和胆固醇的合成,且高锌可通过促进瘦素和胰岛素的分泌调节机体的脂肪代谢。更多还原

【Abstract】 The present study was conducted to investigate the effects of high dietary zinc levels on hepatic lipid metabolism in piglets.One hundred and twenty cross-bred (Duroc×Landrace×Yorkshine) piglets with initial body weight of (26.66±2.45) kg were randomly allocated into 4 groups (control group,trial groups Ⅰ,Ⅱ and Ⅲ) with 3 replicates in each group and 10 piglets in each replicate.Pigs were fed corn-soybean meal-based diets supplemented with 60,300,1 000 and 3 000 mg/kg Zn,respectively.The trial lasted for 16 days after a 7-day adaptation period.The results showed as follows:compared with the control group,1) total triglycerids and low density lipoprotein cholesterol (LDL-C) in serum were significantly increased in all dietary treatment groups(P<0.05);2) in trial group Ⅲ,serum cholesterol and oleate (C18:1) levels were significantly increased (P<0.05),and the concentrations of stearate (C18:0) and octadecadienoic acid (C18:2) were significantly decreased (P<0.05),but the concentration of palmitate (16:0) was unaffected (P>0.05);3) in trial groups Ⅱ and Ⅲ,the levels of stearoyl CoA desaturease (SCD1) mRNA,plasma leptin and insulin were significantly increased (P<0.05),the level of T4 in plasma was significantly decreased (P<0.05),and increasing trends are shown in the levels of T3 and glucagon,but no significant differences were observed (P>0.05).The results indicate that high level of zinc up-regulate the transcription level of SCD1,and enhance the desaturation of C18:0 and synthesis of triglycerid as well as cholesterol.Moreover,high level of zinc can regulate the metabolism of hepatic fatty acids by stimulating the secreation of leptin and insulin.更多还原