Studies On The Effect Of Carotenoids Contents And Tyrosinase Activities Of Red Tilapia By Feeding Pigment Feed

Compared with ordinary tilapia, red tilapia has bright red body color and no black membrane in the cavity, whose growth speed is faster and the meat is more delicious. There are many countries have farmed red tilapia, including Israel, the United States, Thailand, the Philippines, Taiwan of Chinese and so on. For its high economic benefit, not only in southeast Asia and Hong Kong, Macao, Taiwan and other regions are favored by consumers, but also major cities in the south of China are loved by consumers, who has broad market prospects for development. There are various channels for red tilapia entry the market, because of numerous in variety and many of them are produced by self-seeding of more generation, that causing body color of red tilapia is not pure. Even though red tilapia is not belong to ornamental fish, it cannot be denied that the bright degree of the body color are directly affected the sales price and consumer acceptance. In present, At home and abroad, there are rarely research reports in carotinoid content and tyrosinase activity in organizations of red tilapia, and theirs influence on body color. This study was designed to measure carotinoid content and tyrosinase activity in organizations of different body-color red tilapia, then we will get carotinoid content in gill, skin, fin, muscle, eyeball, and tyrosinase activity in skin, scale and liver of red tilapia. Next, we feed them with8%o astaxanthin feed,8%oSpirulina feed,5%o astaxanthin feed and6%oTenebrio molitor feed, and then measuring the carotinoids content and tyrosinase activity in organizations of red tilapia. Analysis of different feeds how to affect red tilapia carotenoids on the expression of between organizations, sedimentary area, and the correlation between the tyrosinase activity. Results are as follows:1. Determined by spectrophotometry the carotinoid content and tyrosinase vitality of red tilapia, there are no significantly difference in the gills, skin and fins in Koshiro, redness and dark spots body color red tilapia (P>0.05). Three kinds of color of red tilapia carotinoid content is significantly different in eyes (P<0.05), redness19.02±13.87mg/kg and dark spots19.28±1.44mg/kg body color of red tilapia, carotinoid content in the eyeballs is significantly higher than the Koshiro one. Carotinoid content in gills of redness body color red tilapia is significantly lower than the skin and fins (P>0.05), it is2.61±0.63mg/kg, compared with the muscles and the eyes of the difference is not significant (P>0.05). Carotinoid content in gill of dark spots body color red tilapia is significantly lower than the skin, fins and eyeballs (P <0.05), it is1.80±0.15mg/kg, and the muscle is no significant difference. in red tilapia organization, there is no significant difference in tyrosinase activity of red tilapia organization (P>0.05).2. The test determine each of red tilapia feed carotinoid content and the influence of the tyrosinase activity by feeding8‰astaxanthin,8‰spirulina,5‰astaxanthin,6%otenebrio feed. Results showed that after feeding white body color red tilapia with8%oastaxanthin feed, whose gills’carotinoids deposition amount is18.05±5.06mg/kg, which higher than the control group (P<0.05). After feeding black body color red tilapia with8%o astaxanthin,5‰astaxanthin and6%otenebrio molitor feed, there is a significant impact in carotenoids deposition of its gills (P<0.05); After feeding white body color red tilapia with8%o astaxanthin, there is a significant improvement in its fins’carotenoid content, which is88.01±55.21mg/kg; after feeding the four kinds of feed, there is a significant impact in its muscles, skin, eyeballs’carotinoid content. Feeding spirulina red tilapia relative tyrosinase activity presents the negative growth, which is0.218±0.759U/g, and have a significant difference amount other groups (P<0.05). After feeding red tilapia with6%otenebrio molitor, whose relative tyrosinase activity is increased to0.647±1.29U/g, which has significant differences amount the control group,8‰astaxanthin, spirulina, tenebrio group (P<0.05).This study analyzed correlates to changes in red tilapia organizations after feeding on different feeds in addition. Found that after feeding the high content of Spirulina feed, there is significant differences in carotenoid content between Muscles and other tissues. After measuring the tyrosinase activity in the skin, we found when carotenoid content in the skin is increased, the tyrosinase activity is reduced; when carotenoid content in the skin is reduced, the tyrosinase activity is increased.3. This study made a preliminary exploration in Sedimentary regularity of carotenoids in the red tilapia. We got an equation of the relation between carotenoid content and different treatment as well as body color: Y=1.4886+0.1822Xi+0.2581X2(Y means carotenoid content, Xi means treatment, X2means body color). Also we got an Sedimentary regularity of carotenoids in the red tilapia:deposition efficiency in fin is the highest, the gill is followed, the next is the eyeball, deposition efficiency in skin and muscle is the lowest.This study was designed to measure carotenoid content and tyrosinase activity in red tilapia organizations, and through artificial adding feed colorant, researching that different of red tilapia feed how to affect carotenoid content and tyrosinase activity. By analyzing the experimental data, showing that under the influence of feed colorant, Carotenoids and tyrosinase activity have correlation in organization, then we got the deposition regularity of carotenoids in red tilapia organization. This study provides theoretical basis for artificial adding feed colorant in the actual production and improving body color of red tilapia.