水產養殖對於我國經濟發展是非常重要的。然而有個非常常見的事實是，當餵魚吃飼料時，釵h飼料在未經魚類攝食前就浪費了。那些被浪費掉的魚飼料，不僅浪費了成本，而且污染了水質。浪費掉的魚飼料與水質以及魚存活率之間的關係，目前尚未被充分的研究。
本研究首先篩選了四種高分子聚合物，以配製成的高分子膜衣液包覆飼料，監測飼料上浮性和崩散速率。研究時選擇1 % Chitosan、1 % Ethyl cellulose 等膜衣液包覆飼料。當飼料被膜衣液包覆後，我們也監測了溶氧量、生化需氧量、總懸浮固體量、氨態氮濃度、pH值、濁度等水中理化參數或水質指標以及生活於其中魚類的存活率。一般而言，實驗結果顯示，經包覆膜衣液飼料之實驗組，減少了濁度，減少了總懸浮固體，且有較高的水中溶氧量。
研究同時也得知幾丁聚醣原料對於魚類紅馬面不具有毒性。似乎包覆1 % Chitosan膜衣液者延長了魚類紅馬面、血艷紅的平均存活時間。相反的，1 % Ethyl cellulose實驗組似乎無效。
總結以上結果，將來有需要繼續加做更多類魚種，更多數目的飼養實驗，以便求得更有意義的統計數據結果。 Aquaculture is very important to the economy of our country. When fish feeds are fed to the fishes, it is very common that many feeds are wasted before they are eaten by the fishes. The wasted feeds are not only a waste to the cost but also pollution to the water quality. The relationships among the wasted feeds, water quality and fish survival rate have not been well studied.
This study first screened the polymers. The polymer solution was coated on the feeds and floatability and disintegration rate of the feeds were monitored. 1 % chitosan and 1 % ethyl cellulose solution were chosen for the coating of the feeds in the study. The effect of coating on the dissolved oxygen, biochemical oxygen demand, total suspended solids, ammonium form nitrogen, pH values, turbidity, and survival rate of the fishes was also monitored. General speaking, the results of this study show that the coated feeds reduced the turbidity, total suspended solids, and increased dissolved oxygen.
Chitosan was not found to be toxic to the Dimidiochromis fuscotaeniatus. It seems that 1 % chitosan coating prolongs the life span of Dimidiochromis fuscotaeniatus and Copadichromis trimaculatus, on the contrary, 1 % ethyl cellulose coating appears not to be effective.
In conclusion, more kinds and numbers of fish should be conducted in the future experiment in order to obtain more meaningful statistic results.
