黄金米虾养殖用水中钙镁离子的含量与比例

Concentration and Proportion of Calcium and Magnesium in Water in Golden Shrimp Neocaridinasp Culture

在水温20~23℃和pH 6.5~7.5条件下,探讨养殖水体中不同钙、镁离子总量和钙、镁离子比例对黄金米虾生长和活力的影响。将黄金米虾饲养在20cm×15cm×20cm的玻璃缸内,每个缸20尾,在本地自来水中添加钙、镁离子总量分别为35mg/L、70mg/L和105mg/L,钙、镁离子质量比分别为1∶1、1∶2、1∶3和1∶4。养殖20d,分别测定碱性磷酸酶、谷丙转氨酶、谷草转氨酶和Na＋/K＋-ATP酶的活性。结果表明,钙、镁离子总量为105mg/L,黄金米虾总的存活率最高,钙、镁离子总量为70mg/L的试验组体长增长率显著高于35mg/L试验组（P〈0.05）,钙、镁离子质量比为1∶3试验组存活率显著高于钙、镁离子质量比为1∶1和1∶4试验组（P〈0.05）。由试验结果可见,钙、镁离子总量为105mg/L,钙、镁离子质量比为1∶3时,可显著增加黄金米虾的活力和存活率。

Influences of concentration and proportion of calcium and magnesium in water on growth and vi tality of golden shrimp （Neocaridinasp） at water temperature of 20--23℃ andpH 6.5--7.5. The golden shrimp was reared in 20 cm× 15 cm× 20 cm glass cylinder at 20 shrimp per cylinder in the water containing total amount of calcium and magnesium at 35 mg/L, 70mg/L or 105 mg/L, with ratio of calcium to mag nesium 1 ： 1, 1 ： 2, 1 ： 3 and 1 ： 4 for 20 days. The activities of alkaline phosphatase （AKP）, alanine aminotransferase （GTP）, aspartate aminotransferase （GOT） and Na＋/K~ ATP （ATPase） enzyme were measured at the end of the experiment. The results showed that the maximal survival rate was observed in the water containing total amount of calcium and magnesium at 105 mg/L, and the shrimp in the water containing total amount of calcium and magnesium at 70 mg/L had significantly higher growth rate in body length than the shrimp in the water containing total amount of calcium and magnesium at 35 mg/L （P〈0.05）. There was significantly higher survival rate in the ratio of calcium to magnesium 1 ： 3 group than that in the ratio of calcium to magnesium= 1 ： 1 and 1 ： 4 groups （P〈0.05）. The findings indicate that significant increase in viability and survival is found in golden shrimp cultured in the water with total a- mount of calcium and magnesium at 105 mg/L, and ratio of calcium to magnesium=l ： 3.