发酵桑叶替代鱼粉对大口黑鲈生长、脂质代谢与抗氧化能力的影响

在基础饲料中用发酵桑叶分别替代0、15%、30%鱼粉,再对30%鱼粉替代水平饲料补充晶体赖氨酸和蛋氨酸,配制成4种等能等氮(CP 42%,GE 18 MJ/Kg)的实验饲料,分别表示为D_1、D2、D_3和D4,饲喂大口黑鲈(初始体质量10 g)8周,研究发酵桑叶替代鱼粉对大口黑鲈生长、脂质代谢和抗氧化能力的影响。结果显示,发酵桑叶替代30%鱼粉会显著降低大口黑鲈的终末体质量、特定生长率(SGR)、脏体比(VSI)和肝体比(HSI),补充晶体氨基酸(CAA)后会明显改善大口黑鲈的生长性能。各实验组蛋白质效率、饲料系数、摄食率、肥满度以及全鱼常规组成均无显著差异。发酵桑叶替代30%鱼粉会显著降低大口黑鲈血清总胆固醇(CHO)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)含量,提高HDL-C/CHO和HDL-C/LDL-C比值。随发酵桑叶替代水平的增加,大口黑鲈血清低密度脂蛋白胆固醇(LDL-C)含量和丙二醛(MDA)含量显著降低,而超氧化物歧化酶(SOD)活性显著升高。研究表明,发酵桑叶替代适宜水平鱼粉不会影响大口黑鲈的生长,而替代鱼粉水平过高会显著抑制大口黑鲈的生长,但可以改善大口黑鲈的脂质代谢和机体抗氧化能力。饲料中补充晶体氨基酸可以提高桑叶的利用率,促进大口黑鲈生长。

Effects of replacing fish meal with fermented mulberry leaves on the growth, lipid metabolism and antioxidant capacity in largemouth bass (Micropterus salmoides)

This experiment was conducted to study the effect of replacement of fish meal by fermented mulberry leaves on the growth, lipid metabolism and antioxidant capacity of largemouth basswith the initial weight (10 g)]. Four isonitrogenous and isoenergetic diets (CP 42%, GE 18 MJ/Kg) were formulated to contain different levels of fermented mulberry based upon the basal diet to replace fish meal 0 (D₁), 15% (D₂), 30% (D₃) and supplement EAA based on 30% (D₄). After 8 weeks, the results showed that final weight (FW), specific growth rate (SGR), viscera somatic index (VSI) and hepatopancreas somatic index (HSI) were decreased significantly when the replacement ratio of fish meal by fermented mulberry was 30%, and supplement crystalline amino acids (CAA) could improve the growth of largemouth bass obviously. There were no significant differences in protein efficiency ratio (PER), feed conversion ratio (FCR), feeding rate (FR), condition factor (CF) and whole body general composition for each test group. The largemouth bass serum of CHO, TG, HDL-C and LDL-C were decreased observably but the ratios of HDL-C/CHO and HDL-C/LDL-C showed the opposite trend. The LDL-C decreased as fermented mulberry ratio increased. Superoxide dismutase (SOD) activities increased significantly as fermented mulberry ratio increased, but malondialdehyde (MDA) decreased markedly. Results of above show that a suitable percentage of fermented mulberry replacement of fish meal has no effect on the growth of largemouth bass. Too high replacement levels would inhibit the growth of largemouth bass, but could improve the lipid metabolism and antioxidant capacity of largemouth bass. Supplement of essential amino acids can improve the utilization of fermented mulberry, and promote the growth of largemouth bass.