卵形鲳鲹幼鱼蛋白质需要量的研究

Optimal dietary protein requirement for juvenile Trachinotus ovatus

为确定卵形鲳鲹(Trachinotus ovatus)幼鱼的蛋白需求量,进行为期8周的摄食生长试验。以鱼粉和豆粕为蛋白源设计6种试验饲料,蛋白质梯度分别为30.32%、35.56%、41.48%、47.86%、51.70%和54.70%。养殖试验在海水网箱中进行,每种饲料投喂3个网箱(1.5 m×1.0 m×2.0 m),每个网箱放养初始体质量(24.39±0.23)g的卵形鲳鲹30尾。试验结果表明,饲料蛋白水平对卵形鲳鲹特定生长率(SGR)及饲料效率(FER)有显著影响。随着饲料蛋白水平的升高,试验鱼SGR及FER均显著增加(P<0.05),而饲料蛋白水平高于41.38%时,各组无显著差异。饲料蛋白水平为47.86%组的卵形鲳鲹获得最好的SGR和FER。随着饲料蛋白水平升高,卵形鲳鲹鱼体蛋白质量分数也显著增加(P<0.05)。根据折线模型确定卵形鲳鲹适宜的蛋白质需要量为45.75%。

An experiment on feeding and growth was conducted to determine the optimal dietary protein requirement for juvenile Trachi- notus ovatus cultured in sea net cages （ 1.5 m × 1.0 m × 2. 0 m）. Fish meal and soybean meal were mixed as protein into the feed at 6 levels （30. 32% , 35.56% , 41.48% , 47.86% , 51.70% and 54. 70% ） and 3 cages per level. Thirty juveniles at the initial weight of （24. 39 ± 0. 23 ） g were fed in each net cage for 56 d. Result demonstrates that dietary protein affects specific growth rate （SGR） and feed efficiency rate （FER） significantly, which both increase with increasing dietary protein level from 30. 32% to 41.48% significantly （ P 〈 0. 05 ）, but show no significant difference above these levels. Juveniles fed with 47.86% protein obtain the best SGR and FER. The protein content in juvenile T. ovatus increases with increasing dietary protein level. Finally, according to the broken-line regression analysis of SGR, the optimal dietary protein requirement for T. ovatuz is about 45. 75%.