淡水、半咸水养殖凡纳滨对虾部分生物学特性的比较

Comparison of Some Biological Characteristics of Litopenaeus vannamei in Freshwater and Brackish Water Culture

试验选取了淡水和半咸水两种盐度下的凡纳滨对虾(Litopenaeus vannamei)各100尾,运用了形态特征测量、肌肉营养成分测定、生理生化指标测定、肌肉质构分析和组织学观察等方法进行其分析比较。结果表明:淡水、半咸水养殖的凡纳滨对虾的形态差异主要集中在头胸甲、腹部、额角和步足。半咸水虾肌肉中粗蛋白和粗灰分含量显著高于淡水虾(P<0.05),而水分含量显著低于淡水虾(P<0.05),两种虾肌肉中的脂肪含量无显著差异(P>0.05)。半咸水虾肌肉硬度是淡水虾1.59倍(P<0.01);淡水虾肌肉的蒸失水率是半咸水虾的1.46倍(P<0.01);淡水虾的肥满度是半咸水虾的1.14倍(P<0.01)。半咸水虾肝胰腺中谷丙转氨酶(GPT)活性是淡水虾的1.32倍(P<0.01),谷草转氨酶(GOT)活性是淡水虾的1.10倍(P<0.05);淡水虾血清中GPT活性比半咸水虾提高了22.12%,GOT活性比半咸水虾提高了45.52%(P<0.05),而GOT/GPT变化均不显著(P>0.05);半咸水虾肝胰腺、血清中总蛋白(TP)含量均显著高于淡水虾(P<0.05);半咸水虾肝胰腺中超氧化物歧化酶(SOD)活性是淡水虾的1.31倍(P<0.05),淡水虾肝胰腺中过氧化氢酶(CAT)活性是半咸水虾的1.35倍,丙二醛(MDA)含量是半咸水虾的1.19倍(P<0.05)。淡水虾脂肪酶(LPS)活性是半咸水虾的1.10倍(P<0.01)。淡水虾的肌纤维直径是半咸水虾的16.71%(P<0.05),半咸水虾的肌纤维密度是淡水虾的37.10%(P<0.05),说明半咸水虾的肉质略高于淡水虾的。可见,半咸水环境中的凡纳滨对虾营养价值、口感及健康状况略微优于淡水环境中的凡纳滨对虾。

In this experiment,100 Litopenaeus vannamei were selected at two salinities of brackish water and freshwater,and their analysis and comparison were carried out by using morphological characteris⁃tics measurement,muscle nutrient composition measurement,physiological and biochemical index mea⁃surement,muscle texture analysis and histological observation.The results show:the morphological differ⁃ences of litopenaeus vannamei in brackish water and freshwater were mainly concentrated in the cephalo⁃thorax,abdomen,frontal horn and footsteps.The contents of crude protein and crude ash in the muscle of brackish water shrimp were significantly higher than those of freshwater shrimp(P<0.05),while the wa⁃ter content was significantly lower than that of freshwater shrimp(P<0.05),while there was no significant difference in the fat content in the muscle of brackish water and freshwater shrimp(P>0.05).The muscle hardness of brackish water shrimp was 1.59 times that of freshwater shrimp(P<0.01).The distillation loss rate of freshwater shrimp muscle was 1.46 times that of brackish wa⁃ter shrimp(P<0.01).The fertility of freshwater shrimp was 1.14 times that of brackish water shrimp(P<0.01).The GPT in the liver and pancreas of brackish water shrimp was 1.32 times that of freshwater shrimp(P<0.01),and the GOT was 1.10 times that of freshwater shrimp(P<0.05).The serum GPT in freshwater shrimp was 22.12%higher than that of brackish water shrimp,and the GOT was increased by 45.52%(P<0.05)compared with that of brackish water shrimp,while the GOT/GPT did not change much(P>0.05).The total protein content in liver,pan⁃creas and serum of brackish water shrimp was significantly higher than that in freshwater shrimp(P<0.05).The SOD activity in the liver and pancreas of brackish water shrimp was 1.31 times that of fresh⁃water shrimp(P<0.05),the CAT activity in freshwater shrimp liver and pancreas was 1.35 times that of brackish water shrimp,and the MDA content was 1.19 times(P<0.05)of brackish water shrimp.The LPS activity of freshwater shrimp was 1.10 times that of brackish water shrimp(P<0.01).The muscle fiber di⁃ameter of freshwater shrimp was 16.71%(P<0.05)of brackish water shrimp,and the muscle fiber density of brackish water shrimp was 37.10%(P<0.05)of freshwater shrimp,indicating that the meat quality of brackish water shrimp is slightly higher than that of freshwater shrimp.It can be seen that the nutritional value,taste and health of Litopenaeus vannamei in the brackish water environment are slightly better than those in the freshwater environment.