日粮能量和蛋白水平对滩羊脂肪组织PPARγ和FABP4 mRNA表达的影响

Effects of Diet Energy and Protein Levels on the mRNA Expression of PPARγand FABP4 in Adipose Tissues of Tan Sheep

旨在研究日粮能量和蛋白水平对滩羊脂肪组织中PPARγ和FABP4mRNA表达的影响。选择健康、体重相近的滩羊112只,公母各半,随机分4组,每组4个重复,每个重复7只羊。参考肉羊饲养标准NY/T（816-2004）,根据生长阶段（22-28、29-35、36-40kg）以目标增重设计标准日粮,每阶段设置0.84×标准（I组）、0.96×标准（II组）、1.08×标准（III组）和1.20×标准（IV组）4个营养水平日粮,分别饲喂4组试验滩羊。于每阶段末每个重复屠宰1只试验羊,取尾部脂肪、肾周脂肪和皮下脂肪组织,通过实时荧光定量PCR检测PPARγ和FABP4mRNA表达水平。结果表明,尾部脂肪组织,在22-28和36-40kg阶段末,II组PPARγ和FABP4mRNA表达量显著高于其他组（P〈0.05）;在29-35kg阶段末,II组FABP4mRNA表达量显著高于其他组（P〈0.05）,且IV组mRNA表达量显著低于其他组（P〈0.05）。肾周脂肪组织,在3个不同阶段末,II组PPARγmRNA表达量显著高于其他组（P〈0.05）,且IV组mRNA表达量显著低于III组（P〈0.05）。在22-28kg阶段末,II组和III组FABP4mRNA表达量显著高于其他组（P〈0.05）;在29-35kg阶段末,II组FABP4mRNA表达量显著高于IV组（P〈0.05）;在36-40kg阶段,I组和II组FABP4mRNA表达量显著高于其他组（P〈0.05）。皮下脂肪组织,在3个阶段末,各组PPARγ和FABP4mRNA表达无显著差异（P〉0.05）。结果表明,日粮能量和蛋白水平对滩羊深层脂肪组织（肾周脂肪）中PPARγ和FABP4mRNA表达的影响大于浅层脂肪组织（皮下脂肪）,对尾部脂肪组织中PPARγ和FABP4mRNA的表达有影响。

The objective of this study was to research the effects of diet energy and protein levels on the mRNA expression of peroxisome proliferator-activated receptorγ（PPARγ）and fatty acid binding protein 4（FABP4）in the adipose tissues of Tan sheep.A total of 112（56♂,56♀）healthy Tan sheep with similar body weight were selected and allocated randomly to 4groups（4replicates in each group,and 7sheep in each replicate）.3stages（22-28,29-35,36-40kg）was classified,and standard diets for each stage were designed according to body weight and expected daily gain in sheep feeding standard of NY/T（816-2004）,4diets with energy and protein levels of0.84×Standard（group I）,0.96×Standard（group II）,1.08×Standard（group III）,1.20×Stand-ard（group IV）were assigned to feed sheep in each group,respectively.At the end of each stage,one sheep from each replicate was slaughtered,and samples of tail fat,perirenal fat and subcutaneous fat were collected for analyzing the mRNA expression of PPARγand FABP4 by Real-time quantitative PCR.The results showed as follows：In tail fat,PPARγand FABP4 mRNA expression levels was significantly higher in group II than other groups at the end of stage 22-28and36-40kg（P〈0.05）;FABP4 mRNA expression levels was highest in group II,and lowest in group IV at the end of stage 29-35kg（P〈0.05）.In perirenal fat,PPARγ mRNA expression levels was significnatly higher in group II,and significantly lower in group IV compared with group III at the end of 3stages（P〈0.05）.FABP4 mRNA expression levels was higher in group II and III at the end of stage 22-28kg（P〈0.05）;FABP4mRNA expression levels was higher in group II compared with group IV at the end of stage 29-35kg（P〈0.05）;FABP4mRNA expression levels was higher in group I and II at the end of stage 36-40kg（P〈0.05）.In subcutaneous fat,there was no significant difference between different groups at the end of 3stages（P〈0.05）.These results indicated that the effect of diet energy and protein levels on PPARγand FABP4 mRNA expression was greater in deep fat tissue（perirenal fat）than that in superficial fat tissue（subcutaneous fat）in Tan sheep.The diets with different energy and protein levels had an effect on PPARγand FABP4 mRNA expression of tail fat in Tan sheep.