饲料蛋白对翘嘴鲌蛋白质合成能力的影响

Effect of dietary protein on protein synthesis capacity of Culter alburnus

试验Ⅰ:以鱼粉为蛋白源,配制5个蛋白水平的等能、等必需氨基酸(EAA)平衡关联度的半精制饲料,探讨饲料蛋白水平对翘嘴鲌蛋白质合成能力的影响。结果表明,饲料蛋白水平为40.89%时翘嘴鲌特定生长率(SGR)显著高于31.04%、35.51%组(P<0.05),但与46.62%、50.33%组之间差异不显著。翘嘴鲌白肌RNA和RNA/DNA随饲料蛋白质水平的提高而升高,40.89%组的白肌RNA/DNA显著高于31.04%和35.51%蛋白组(P<0.05),但与46.62%、50.33%蛋白组间差异不显著。白肌RNA/DNA、RNA/Prot(蛋白质)分别与饲料蛋白水平和SGR显著正相关(P<0.05)。试验Ⅱ:用大豆蛋白分别替代0.0%、13.5%、27.0%、40.5%、54.0%的鱼粉蛋白,配制5个EAA平衡关联度的等蛋白、等能的半精制饲料,探讨饲料中大豆蛋白替代鱼粉蛋白对翘嘴鲌蛋白质合成能力的影响。结果表明:当饲料中大豆蛋白替代量为54.0%时,翘嘴鲌的SGR极显著低于对照组(P<0.01);当替代量达40.5%时,白肌RNA、RNA/DNA和RNA/Prot都显著低于对照组(P<0.05)。白肌RNA/DNA、RNA、RNA/Prot分别与大豆蛋白替代鱼粉蛋白的量呈显著负相关(P<0.05),与SGR显著正相关(P<0.05)。

In Experiment Ⅰ ： 5 isoenergetic and the same relativity of essential amino acid balance semi-purified diets containing different protein levels were prepared in order to investigate the effect of dietary protein level on protein synthesis capacity of Culter alburnus juveniles. The results showed that specific growth rate （SGR） were significantly influenced by dietary protein levels （P 〈0. 05）. SGR of the fishes fed on 40. 89% protein diets was significantly higher than that of the fishes fed on 31.04%, 35.51% protein diets （ P 〈 O. 05）, but it was not significantly different from that of the fishes fed on 46. 62% and 50. 33% protein diets （P 〉 0. 05）. RNA and RNA/DNA in white muscle increased with increasing dietary protein level, and those of 40. 89% treatments were significantly higher than those of 31.04% and 35.51% treatments but not significantly different from those of 46. 62% and 50. 33% protein level treatments. RNA/DNA and RNA/Prot in white muscle were in a positive correlation with SGR and dietary respectively （ P 〈 0. 05 ）. In Experiment Ⅱ ： five isonitrigenous and isoenergetic semi-purified diets of different relativity of essential amino acid balance with soybean protein replacing 0. 0% , 13.5% , 27.0% , 40.5% , 54. 0% of fish meal protein, were formulated to determine the effect of replacement level of soybean protein for fish meal protein on protein synthesis capacity of Culter alburnus juveniles. When the replacement level for fish meal protein with soybean protein was 13.5% , 27.0%, 40. 5%, it was not significantly different in SGR compared with control group （ P 〉 0. 05 ）, but significantly higher than that in fishes fed on 54. 0% replacement of soybean protein （ P 〈 0. 01 ）. When the replacement level for fish meal protein with soybean protein was 40. 5%, RNA, RNA/DNA and RNA/Prot in white muscle were significantly lower than those in control group （P 〈 0. 05 ）. RNA, RNA/DNA and RNA/Prot in white muscle were in a positive correlation with SGR （ P 〈 0. 05 ） but in a negative correlation with replacement level.