将黄颡鱼种放养在网箱中,投喂蛋白质含量30.0%、38.0%或46.0%和维生素C磷酸酯0、500、1000或1500 mg?kg-1的半纯饲料.50 d的饲养表明:饲料蛋白质含量在38%～40%时,鱼的特殊生长率和蛋白质效率最高,饲料系数最低.饲料维生素C磷酸酯含量为847、850、994和634 mg?kg-1时,血清总蛋白、γ球蛋白、溶菌酶活性最高,超氧化物歧化酶活力最低.饲料蛋白质含量从30%上升到38%时,鱼体蛋白含量由60.95%升到69.86%,脂肪由29.27%降至21.69%;达46%时,鱼体蛋白(64.35%)含量下降,而脂肪(26.06%)含量上升.饲料粗蛋白含量为38%时,鱼肌肉中饱和与单不饱和脂肪酸的含量分别极显著地低于和显著高于饲料粗蛋白为30%和46%组.后两组鱼肌肉n-3/n-6值极显著和显著高于饲料蛋白含量为38%时,两个高蛋白饲料组中,鱼肌肉中n-6系列多不饱和脂肪酸和亚麻酸含量极显著和显著高于饲料蛋白30%组.黄颡鱼种饲料中蛋白质和维生素C的最适含量分别为35.58%～40.60%和600～800 mg?kg-1.

Juvenile yellow catfish Pelteobagrus fulvidraco （Richardson） with 18.0 g in body weight were stocked into 36 net cages of 60 cm ? 60 cm ? 120 cm each and fed semi-purified formulated feed containing 30%, 38% and 46% of dietary protein and supplemented with four levels of ascorbic acid-2-phosphate （AA） （0, 500, 1000, 1500 mg?kg^- 1 diet, ） at 22 ? 3 ℃ for 50 days. The results showed that the fish fed the formulated feed containing 38.0% - 40.0% dietary protein bad the maximal special growth rate （ SGR）, and protein efficiency ratio （PER） and the minimal feed coefficient （ FC）. The catfish had the maximal levels of total plasma protein, γ-globulin, and activities of lysozyme and the minimal activity of superoxide dismutase when fed 847, 850, 994 and 634 AA mg?kg^-1 diet. In the fish fed the formulated feed varying from 30% to 38% in dietary protein, the protein in muscles increased from 60.95% to 69.86%, and the lipid decreased from 29.27% to 21.69%, whereas the fish fed the formulated feed containing 46% dietary protein bad a decrease in protein （64.35 % ） and an increase in lipid （26.06 % ） levels in muscles. There were significantly higher saturated fatty acid levels （SFA） （ P 〈 0.01 ）and monounsaturated fatty acid levels（ P 〈 0.05）in museles in the fish fed the feed containing 38% dietary protein than those in the fish fed the feed containing 30% and 46% dietary protein. There were significantly higher linolenic acid and n - 3 polyunsaturated fatty acid （ n - 3 PUFA） levels in muscles in the fish fed the 38% and 46% （ P 〈 0.01, P 〈 0.05） dietary protein feeds than those in the fish fed the 30% dietary protein feeds. It was found.that there was significantly higher n - 3/n - 6 ratio in the 30% and 46% dietary protein groups than in the 38% dietary protein group. For yellow catfish juveniles, the optimal dietary protein and vitamin C levels have been considered as 35.58 - 40.60% and 600 - 800 mg? kg^-1, respectively.

辽宁省自然科学基金