吳郭魚目前是臺灣水產養殖業年產量最多的魚種。紅色吳郭魚 (Oreochromis sp.) 由莫三比克種吳郭魚突變而來。本研究目的為探討在飼料中添加不同來源與濃度的類胡蘿蔔素對紅色吳郭魚魚苗體表增豔效果之影響。本實驗所使用之色素添加物為兩種不同來源之類胡蘿蔔素，分別為由基因轉殖之大腸桿菌所含之類胡蘿蔔素與人工合成的還原蝦紅素。實驗飼料分為五組，分別為對照組與添加基因轉殖大腸桿菌所含類胡蘿蔔素 50 與 100 mg/kg (E-50、E-100) 及添加人工合成還原蝦紅素 50 與 100 mg/kg (R-50、R-100)。實驗結果顯示，以色差計測量所得數據，色彩平均差異值 (△E) 為 8.06 ~ 14.89，已到達目視即可直接察覺差異的標準 (△E > 6.0)；魚皮類胡蘿蔔素含量測定的結果，以對照組最低，為 0.25 mg/100g skin，其餘各組以E-100組為最高，類胡蘿蔔素含量為 0.84 mg/100g skin。依據本次實驗結果，要增加紅色吳郭魚魚苗在體表增豔效果的表現，以基因轉殖大腸桿菌之類胡蘿蔔素做為色素來源較佳。
|標題title(英)：||Effects of Dietary Carotenoid Supplements on the Integument Pigmentation of Red Tilapia (Oreochromis sp.)|
|作者 auther(英)：||You-Syu Huang, Wen-Liang Liao and Yuan-Shing Ho|
|摘要abstract(英)：||Tilapia is now the primary product of the aquaculture industry in Taiwan. Red tilapia (Oreochromis sp.) was mutated from the Mozambique tilapia species. The purpose of this study was to explore the effects of dietary carotenoid supplements on the integument pigmentation of red tilapia (Oreochromis sp.).
Experiments were conducted to provide two different sources of carotenoids: gene transferred Escherichia coli powder and synthetic astaxanthin. The mean weight of the red tilapia tested was about 2.6 g. Fish were divided into five groups with differing experimental diets: a control group (Ctrl), an E-50 group, an E-100 group, an R-50 group, and an R-100 group. The diets of the fish in the E-50 group and the E-100 group were supplemented with gene transferred Escherichia coli powder with two different carotenoid contents, 50 and 100 mg/kg, respectively. The diets of the fish in the R-50 group and the R-100 group were supplemented with synthetic astaxanthin at 50 and 100 mg/kg, respectively. The duration of the experiment was 10 weeks. Fish integument was measured with a tristimulus colorimeter, and further quantified for skin pigment.
The results suggested that carotenoid supplements did not have obvious effects on the growth performance and feed efficiency, but did improve pigmentation by enhancing a and b values in the red tilapia. In this trial, the △E varied from 8.06 to 14.89, while the content of carotenoids in the red tilapia tested varied from 0.25 to 0.84 mg/100 g.