饲料蛋白水平对眼斑双锯鱼幼鱼生长性能和体成分的影响

Effects of Dietary Protein Levels on Growth Performance and Body Composition in Juvenile False Clown Fish,Amphiprion ocellaris

为确定眼斑双锯鱼幼鱼人工配合饲料中合适蛋白水平,试验研究了饲料蛋白水平对眼斑双锯鱼幼鱼生长、饲料转化率和体成分的影响。养殖试验在循环水系统中进行,初始体质量为(0.085±0.002)g的幼鱼随机分配到6个处理组(每组3个平行,每个平行40尾),分别投喂蛋白水平38.11%、40.91%、44.16%、47.21%、50.02%和53.16%的人工饲料,试验持续56d。不同蛋白水平饲料对眼斑双锯鱼幼鱼质量增加率、特定生长率、饲料系数、蛋白质效率以及全鱼的体成分等均有显著影响。饲料蛋白水平为38.11%~50.02%时,随着饲料蛋白水平的增加,眼斑双锯鱼幼鱼的质量增加率和特定生长率呈增加的趋势,饲料蛋白水平为53.16%时略有下降。经回归分析,当饲料蛋白水平为51.8%时,质量增加率最大;蛋白水平为51.1%时,特定生长率最大。饲料系数也随着饲料蛋白水平增加而呈现先降后升的趋势,饲料系数谷值出现在蛋白水平为47.21%试验组,而蛋白质效率则相反。经回归分析,当饲料蛋白水平为47.5%时,饲料系数最小;饲料蛋白水平为47.8%时,蛋白质效率最大。全鱼粗蛋白随饲料蛋白水平升高呈增加趋势,但到一定水平后维持该水平不再增加,而粗脂肪则随饲料蛋白水平升高呈先降后升的趋势。综合生长、饲料转化率和体成分等指标,本试验条件下眼斑双锯鱼幼鱼适宜的饲料蛋白水平为47.5%~51.8%。

An 8-week feeding trial was conducted to investigate the effects of different protein levels in diet on growth performance, body composition of juvenile false clown fish Amphiprion ocellaris. The fish with initial body weight（0. 085 ±0. 002） g were randomly divided into six treatments with triplicate groups, and fed diets containing 38.11%, 40.91%, 44.16%, 47.21%, 50.02% or 53.16% protein in a circulating sea water system. The weight gain （WG） and specific growth rate （SGR） increased with protein level from 38.11% to 50.02% and decreased in the fish fed the diet containing 53.16% protein level. Regression a- nalysis indicated that the maximal WG was found at 51.8% protein level and the maximal SGR was found at 51.1% protein level. Moreover, with the increase in protein level, feed conversion ratio （FCR） showed a trend of decline after rising first. The minimal FCR appeared at 47.21% protein level, and the trend of protein efficiency ratio （PER） was just the opposite. Regression analysis revealed that the minimum FCR was found at 47.5% protein level and the maximal PER was found at 47.8- protein level. Whole-body protein content increased as dietary protein level increasing, without increased at a certain high level. Whole-body crude fat decreased first and then increased with the increasing dietary protein level. Consider- ing indicators such as growth, feed efficiency and body composition, the suitable dietary protein level of the juvenile false clown fish should be 47.5- to 51.8% under this experimental condition.