草鱼不同部位肌肉营养成分、肌纤维特性以及脂肪代谢相关基因的表达

为了探讨草鱼(Ctenopharyngodon idella)不同部位肌肉品质的差异,本研究选取体质量为(1 026.10±145.55)g的草鱼,检测了背部、腹上部、腹底部和尾部肌肉的营养成分、肌纤维组织结构特性以及脂肪代谢相关基因的表达。结果表明,草鱼腹底部肌肉的粗脂肪含量显著高于背部、腹上部和尾部肌肉,而水分含量则显著降低;背部肌肉粗蛋白含量显著高于腹上部、腹底部和尾部肌肉。腹上部肌肉的肌纤维直径显著高于背部、腹底部和尾部肌肉,但其肌纤维密度则显著降低,而最高的肌纤维密度出现在腹底部肌肉;草鱼背部和尾部肌肉肌纤维密度无显著差异。草鱼腹底部肌肉的脂蛋白脂肪酶基因mRNA表达量显著高于草鱼背部、腹上部和尾部肌肉。脂肪酸合成酶和乙酰辅酶A羧化酶α的mRNA表达量在草鱼背部、腹上部、腹底部和尾部肌肉之间无显著差异。研究表明,草鱼不同部位的肌肉营养特性存在显著性差异,肌肉脂肪含量与肌纤维直径呈负相关,与脂蛋白脂肪酶基因的表达量呈正相关。

Nutritional compositions,muscular fiber properties,and the expression of lipid metabolic related genes in different parts of muscle in Ctenopharyngodon idella

In order to investigate muscular quality in different parts of muscle in Ctenopharyngodon idella, we assayed the nutritional composition, muscular fiber properties, and the mRNA expression level of lipid metabolism related genes in the dorsal muscle, the upper part of the abdominal muscle, the bottom part of the abdominal muscle, and the tail muscle in C. idella(the body weight 1026. 10 ± 145. 55g) . The results showed that the crude lipid content in the bottom part of the abdominal muscle was significantly higher than that in the dorsal muscle, the upper part of the abdominal muscle, and the tail muscle. The highest moisture content was found in the bottom part of the abdominal muscle. The significant highest crude protein content occurred in the dorsal muscle compared to the other parts of muscle. The largest muscular fiber diam-eter was observed in the upper part of the abdominal muscle. The highest muscular fiber density was shown in the bottom part of the abdominal muscle. There were no significant difference in muscular fiber density between the dorsal muscle and the tail muscle. The mRNA expression level of lipoprotein lipase in the bottom part of the abdominal muscle was significant-ly higher than that in the dorsal muscle, the upper part of the abdominal muscle, and the tail muscle. There was no signifi-cant difference in the mRNA expressions level fatty acid synthase and acetyl-CoA carboxylaseαamong the different parts of muscle. It is concluded that there are significant different nutritional compositions among the different parts of muscle in C. idella. The lipid content of muscle was negatively correlated with the muscular fiber diameter, and positively correlated with the mRNA expression level of lipoprotein lipase.