Studies on the Lipid Levels of Newly Developed Dry Pellets for Sea Fish and the Prevention of in vivo Lipid Peroxidation

本研究旨在开发一种低不饱和度的黄尾鱼软干颗粒（SDP），以减少体内脂质过氧化反应引起的各种鱼类疾病的发生，提高养殖鱼类的品质。通过将沙丁鱼油和棕榈油以1：0（饮食1）、1：1（饮食2）和1：2（饮食3）的比例混合来制备具有不同不饱和度水平的三种SDPs。分别用83 g和116 g的黄尾鱼幼鱼饲喂2个月。饲喂饮食1和2的鱼的平均体重比饲喂饮食3的鱼的平均体重高得多。饲料2和3的鱼的血浆TBA值和组织脂质含量低于鱼饲料1。肌肉注射苯肼后，在喂食饲料3的鱼中观察到高血浆胆红素含量。此外，在接种引起黄疸的杆状细菌后，在饲喂饲料3的鱼中观察到最高的TBA值和胆红素含量。这些结果表明，以1：1的比例用棕榈油代替沙丁鱼油作为饲料脂质可能有助于黄尾鱼的SDP。

This study was conducted to develop a soft dry pellet (SDP )with a low unsaturation for yellowtail in order to reduce the occurrence of various fish diseases due to in vivo lipid peroxidation progression as well as to improve the quality of the cultured fish. Three kinds of SDPs with different levels of unsaturation were prepared by mixing sardine oil and palm oil in ratios of 1 : 0 (diet 1), 1 : 1 (diet 2), and 1 : 2 (diet 3). Juvenile yellowtail weighing 83g or 116g were fed for two month on these SDPs. The average body weights of fish fed diets 1 and 2 were quite higher than that of fish on diet 3. Plasma TBA values and tissue lipid contents of fish fed diets 2 and 3 were lower than that of fish diet 1. After an intramuscular injection of phenylhydrazine, high plasma bilirubin content was observed in fish fed diet 3. Moreover, after the inoculation of rod-shaped bacteria causing jaundice, the highest TBA value and bilirubin content were observed in fish fed diet 3. These results suggest that replacement of sardine oil by palm oil in ratio of 1 : 1 as the dietary lipid may enable in the SDP for yellowtail.