Effects of dietary different carotenoids supplements on pigmentation of orange Honey gourami (Trichogaster chuna)

• Main Authors: Chun-Chia Liang, 梁峻嘉
• Other Authors: Wen-Liang Liao
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/7kn5v2

碩士 === 國立臺灣大學 === 漁業科學研究所 === 105 === This study focused on the different kinds and concentrations of carotenoids in diet for effects of pigmentation of Trichogaster chuna var. orange, to find out the optimal amount to enhance the skin color, and speculated that the carotenoids for the metabolism and accumulation. The experiment was conducted for 9 weeks. The first 3 weeks of feeding without carotenoids feed on the domestication of fish and fade. After 6 weeks of coloring experiments, and add zeaxanthin (Z), free-type astaxanthin (A), and ester-type astaxanthin (E) in the diet. The experiments divided into 10 groups: 0(Control)、Z25、Z50、Z75，A25、A50、A75，E25、E50、E75 (mg/kg diet). Before feeding the carotenoids diet, the percent weight gain and feed efficiency of each group was measured at weeks 0, 2, 4, and 6, respectively. The color of the fish body was quantified under the same condition, the color change was measured with color difference (△E). The results of this study indicate that the addition of carotenoids to the diet of the Trichogaster chuna var. orange was not significantly different for the percentage of weight gain and feed efficiency. The residual ratio of zeaxanthin was about 82% in the diets, about 57% in the free-type astaxanthin, and about 75% in the ester-type astaxanthin. The ester-type astaxanthin has a better preservation effect than the free-type astaxanthin. The content of carotenoids in the extracted fish skin and carotenoid content in the zeaxanthin group ranged from 5.86-7.11 mg / 100g. The content of free -type astaxanthin group ranged from 5.07-7.76 mg / 100g, while the content of ester-type astaxanthin group ranged from 6.96-7.94 mg / 100g, and the content of ester-type astaxanthin E75 was the highest. The addition of different carotenoids, fish skin with carotenoids in the amount of diet are added with the increase. The color difference value (△E) of the pelvic fin is greater than 6 in the group of pigment added, and reach the naked eye recognition standard. In the area below lateral line, only the addition of zeaxanthin group and E75 group to the naked eye recognition standards. The operculum color was identified by the naked eye with the zeaxanthin group. According to the accumulation of carotenoid in skin and color difference, zeaxanthin has higher accumulating capacity and skin coloring performance than that of astaxanthin. Ester-type astaxanthin has a higher accumulation than free-type astaxanthin. It is suggested that the addition of 75 mg / kg zeaxanthin can increase the coloring ability of Trichogaster chuna, 75mg / kg of free-type astaxanthin and 50mg / kg of ester-type astaxanthin.