蚯蚓渣粉替代鱼粉对大口黑鲈生长和肌肉品质的影响

The effect of fish meal replacement by earthworm by-products on the growth and muscle quality of largemouth bass(Micropterus Salmoides)

为探究蚯蚓渣粉替代鱼粉日粮对大口黑鲈(Micropterus salmoides)生长性能和肌肉品质的影响,实验设计蚯蚓渣粉替代不同比例鱼粉(0%、10%、20%、30%)的4种饲料,分别记为Control、D10、D20和D30组,进行四个月养殖实验。结果显示,D10组大口黑鲈终末重和特定生长率显著高于Control组,D20组大口黑鲈肌肉保水能力显著高于Control组,D30组大口黑鲈肌肉弹性和回复性显著低于Control组。并且3个实验组大口黑鲈全鱼和肌肉中蛋白质含量和肌纤维面积(1000~5000μm^(2))的百分比显著高于Control组,而碱性磷酸酶(AKP)、谷草转氨酶(GOT)和谷丙转氨酶(GPT)活力无显著性差异。此外,与Control组相比,蚯蚓渣粉替代鱼粉实验组可通过上调肌肉生长相关基因的表达水平来促进肌纤维新生和生长,进而改善肌肉品质。D20组肌肉保水能力、蛋白质含量、肌纤维面积(1000~5000μm^(2))和胰岛素样生长因子1基因表达量均显著高于Control组,其肌肉弹性和回复性均显著低于Control组。因此,综合分析生长性能及肌肉品质结果,建议大口黑鲈日粮中蚯蚓渣粉替代鱼粉的最适替代比例为20%。

The effects of replacing fishmeal with earthworm by-products on the growth performance,conventional nutrients,water holding properties,muscle texture characteristics and muscle fiber growth of largemouth bass(Micropterus salmoides)was investigated to evaluate the appropriate proportion of earthworm by-products to replace fishmeal,alleviate the restriction of fishmeal shortage on the development of healthy aquaculture production,and realize the recycling of resources by turning waste into treasure.Earthworm by-product with different substitution ratios(0%,10%,20%,30%)was selected to replace fishmeal,which was recorded as Control,D10,D20 and D30 groups,respectively,and was cultured for four months.The results showed that compared with the Control group,the average weight and specific growth rate of largemouth bass in the D10 group were significantly increased.The muscle water holding capacity of the D20 group was significantly improved.The muscle elasticity and recovery were significantly reduced.With the increase of the substitution ratio of earthworm by-products,the percentage of protein content and muscle fiber area(1000-5000μm^(2))in whole fish and muscle of largemouth bass increased significantly.There was no significant difference in the enzyme activities of AKP,GOT and GPT.Earthworm by-products could promote myofiber proliferation and growth by improving growth performance and up-regulating the expression levels of muscle growth-related genes(scopoletin,myogenic regulatory factor 6,insulin-like growth factor 1 and insulin-like growth factor 2),thereby improving muscle quality.The D20 group was significantly higher than the Control group,which included the muscle water-holding capacity,protein content,muscle fiber area(1000-5000μm^(2))and the expression level of insulin-like growth factor 1 genes.The muscle springiness and resilience of the D20 group were significantly lower than that of the Control group.Therefore,based on a comprehensive analysis of growth performance and muscle quality data,it is recommended that the optimal replacement ratio of earthworm by-products to fish meal in the diet of largemouth bass is 20%.