Diatomite and Dietary Sodium Chloride Decrease Cu^(2+) Accumulation and Induction of Metallothionein Expression on Tilapia Juvenile (Oreochromis mossambicus ) Upon Exposure to Waterborne Copper

矽藻土與含鈉飼料降低銅暴露後之吳郭魚幼魚之銅累積量與誘導金屬硫蛋白之表現

陳雨禪(Yu-Chan Chen) ； 李茂田(Maw-Tien Lee) ； 鍾國仁(Koa-Jen Jong) ； 吳淑美(Su-Mei Wu)

《臺灣水產學會刊》 40卷2期 (2013/06) Pp. 79-88

https://doi.org/10.29822/JFST.201306_40(2).0001

摘要

本研究的目的是利用矽藻土過濾養殖水與應用含氯化鈉之飼料投餵給暴露在銅環境下之吳郭魚幼魚食用，觀察其是否具有降低銅累積的效應，本研究的實驗設計包括無任何處理組（空白組：B）；另有四組之銅暴露組，（1）暴露3.15μM銅處理72小時（對照組：C）；（2）鈉飼料投餵組（Na投餵6星期後再進行銅暴露）；（3）矽藻土過濾組（Si），在銅暴露時同時以矽藻時過濾；（4）鈉飼料投餵組加上矽藻土過濾組（Na＋Si）。結果顯示不論是鈉飼料投餵組或是矽藻土過濾組都可以明顯降低吳郭魚幼魚之銅累積量，以及增加金屬硫蛋白（metallothionein）之表現量，同時不會影響魚體之成長。之後我們模擬一般在養殖場除藻或殺蟲時處理銅之模式，即是以6.26μM銅處理24小時後，再以相同濃度的銅再處理一次，也是暴露24小時，然後比較兩者對魚體銅累積降低之效果，結果在銅處理24小時時，納飼料與矽藻土組就比銅暴露組呈現降低70%銅累積的效果，在第二次銅暴露後，矽藻土組就比銅暴露組呈現降低89%銅累積的效果，然而同時進行鈉飼料投餵加上矽藻土過濾組的銅累積降低率，並未優於單用鈉飼料投餵或單用矽藻土過濾的效果好，因此我們推論利用矽藻土過濾含銅之養殖水與應用含氯化鈉之飼料投餵給養殖魚類，皆具有降低養殖魚之銅累積的效果。

關鍵字

銅 ； 矽藻土 ； 吳郭魚 ； 金屬硫蛋白 ； 飼料鈉

並列摘要

This study aims to estimate the effectiveness of dietary NaCl in fish and aquatic water filtered with diatomite, to determine whether both treatments could practically be applied to aquaculture to reduce Cu^(2+) accumulation in fish. The experimental designs were included one blank (B) group of fish which was without any treatment, and four Cu^(2+) exposure groups (3.15 μM Cu^(2+) exposure for 72 h): C group of fish was treated with Cu^(2+) exposure; Na group of fish was treated with Cu^(2+) exposure after dietary NaCl for 6 weeks; Si group of fish was treated with Cu^(2+), but the exposure water was filtered by diatomite; Na+Si group of fish was treated with Cu^(2+) exposure after dietary NaCl for 6 weeks, and the exposure water was filtrated by diatomite. Results showed that both diatomite and dietary NaCl treatments induced significantly increased metallothionein expression and reduced Cu^(2+) contents in fish, but did not interfere with the growth, or whole-body water or Na+ homeostasis of juvenile tilapia. In treatment groups, Cu^(2+) levels decreased in the water and in the whole fish body after 6.26 μM CuSO4 exposure. According to the data, we suggested that both diatomite filtration and dietary NaCl have a potential to decrease Cu^(2+) accumulation and to induce metallothionein expression on fish.

並列關鍵字

copper ； diatomite ； tilapia ； metallothionein ； dietary sodium