Ca^(2+)、Mg^(2+)、盐度对凡纳滨对虾存活、生长及风味的影响

Effect of Ca^(2+), Mg^(2+) and salinity on survival, growth and shrimp taste of Litopenaeus vannamei

采取L49(78)安排7水平Ca2+、Mg2+、盐度正交试验,开展60d凡纳滨对虾养殖试验,通过比较凡纳滨对虾成活率、日均增长值、日均增重量及鲜味氨基酸含量,分析养殖水体中Ca2+、Mg2+、盐度三因子对凡纳滨对虾存活、生长及虾体风味的影响;采取L8(27)安排2水平Ca2+、Mg2+、盐度正交试验,分析养殖水体中Ca2+、Mg2+、盐度三因子间交互作用对凡纳滨对虾存活、生长及虾体风味的影响。结果表明:水体中Ca2+、Mg2+、盐度对成活率和虾体鲜味氨基酸都有显著影响(P<0.05),Ca2+、Mg2+对凡纳滨对虾生长具有显著影响(P<0.05),其中Mg2+对成活率影响最大,Ca2+对生长影响最大,而鲜味氨基酸受盐度影响最大。Ca2+浓度为100mg/L和400mg/L,Mg2+为1200mg/L,盐度为10时,成活率最高;Ca2+≥200mg/L与Mg2+≥300mg/L时,生长速度无明显变化,Ca2+浓度为100mg/L,Mg2+浓度为150mg/L,盐度为10~20时,体长和体质量增加最快;Ca2+、Mg2+含量与盐度越高,鲜味氨基酸含量越高,Ca2+浓度为400mg/L,Mg2+浓度为750mg/L,盐度为35和20时,风味氨基酸含量最高;低盐、低钙、低镁水体显著降低了凡纳滨对虾的生长存活;Ca2+与Mg2+对成活率及体质量日均增长具有显著的交互作用影响,Ca2+与盐度对成活率具有显著的交互作用影响,Mg2+与盐度对各试验指标均没有显著影响。

Salinity, calcium and magnesium play key roles in the survival and growth of Litopenaeus van-namei. In the present study, two experiments were conducted to test the effect of salinity, calcium and magnesium on survival, growth and flavor of the shrimp, L. vannamei. The first experiment designed using the Taguchi method with three factors （Ca2＋, Mg2＋ and salinity）, each with 7 levels （L49）, was run for 60 days to analyze the independent role of Ca2＋, Mg2＋ and salinity on the survival, growth and flavor of L. vannamei. Additionally, a L8 test of three factors, each with two levels, was conducted to analyze the in-teraction of Ca2＋, Mg2＋ and salinity on the survival, growth and flavor of L. vannamei. The results showed that Ca2＋, Mg2＋ and salinity significantly affect the survival and flavor amino acids of L. vannamei, and Ca2＋ and Mg2＋ significantly influence the growth. The highest survival rate was observed at Ca2＋ of 100 mg/L and 400 mg/L, Mg2＋ of 1200 mg/L, and salinity of 10; The growth did not significantly change at Ca2＋ of≥200 mg/L, and Mg2＋ of ≥300 mg/L. The highest length and weight gains were found at Ca2＋ of 100 mg/L, Mg2＋ of 150 mg/L and salinity of 10-20; The content of flavor amino acids increased with the increase of Ca2＋, Mg2＋ and salinity, and the highest content of flavor amino acids occurred at Ca2＋ of 400 mg/L, Mg2＋ of 750 mg/L, and salinity of 20 and 35. Low salinity and concentration of Ca2＋, Mg2＋ signifi-cantly reduced the growth and survival of the shrimp. The interaction between Ca2＋ and Mg2＋ was signifi-cant on survival and daily weight gain of the shrimp, and the combined effect of Ca2＋ and salinity was sig-nificant on survival of the shrimp. However, the interaction between Mg2＋ and salinity was not significant on any of the three parameters.