饲料脂肪水平对褐菖鲉血清生化指标、免疫及抗氧化酶活力的影响

Effects of dietary lipid levels on serum biochemistry indices,immunity, and antioxidant activity in Sebastiscus marmoratus

以鱼粉为脂肪源,设脂肪水平分别为6.1%(A组)、9.5%(B组)、12.4%(C组)、15.1%(D组)、18.5%(E组)的5种实验饲料,对平均初始体质量为(27.56±0.19)g的褐菖鲉(Sebastiscus marmoratus)进行为期60 d的饲养实验,探讨饲料脂肪水平对褐菖鲉血清生化指标、免疫及抗氧化酶活力的影响。结果表明:(1)随着饲料中脂肪水平的升高,褐菖鲉血清中的高密度脂蛋白胆固醇(HDL-C)呈逐渐升高的趋势,E组最高,显著高于A组、B组和C组(P<0.05),低密度脂蛋白胆固醇(LDL-C)表现为先上升后下降的趋势,C组显著高于D组和E组(P<0.05),而甘油三酯(TG)和总胆固醇(CHO)呈下降的趋势,D组、E组显著低于A组、B组和C组(P<0.05),总蛋白(TP)含量在各组间差异不显著(P>0.05);(2)褐菖鲉血清免疫球蛋白M(IgM)含量随脂肪水平的升高呈现先上升后下降的趋势,C组显著高于其他各组(P<0.05),溶菌酶(LZM)活力也呈现先上升后下降的趋势,C组显著高于A组、D组和E组(P<0.05);(3)肝超氧化物歧化酶(SOD)活力、过氧化氢酶(CAT)活力和总抗氧化能力(T-AOC)随着饲料中脂肪水平的升高呈现先上升后下降的趋势,C组显著高于其他各组(P<0.05),丙二醛(MDA)含量则呈现逐渐上升的趋势,其D组和E组显著高于其他各组(P<0.05)。血清中SOD活力随脂肪水平升高呈现上升趋势,D组和E组显著高于A组、B组、C组(P<0.05);血清CAT活力也表现为上升的趋势,但各组之间差异不显著(P>0.05)。综上可见,饲料中适宜的脂肪水平(12.4%)可明显改善褐菖鲉的免疫功能与抗氧化能力。

We evaluated the effects of dietary lipid levels on serum biochemistry indices,immunity,and antioxidant function in Sebastiscus marmoratus.Juvenile fish（average initial body weight： 27.56±0.19 g） were randomly divided into 5 groups and fed diets containing different levels of lipid（from fish meal） for 60 d： diet A（6.1%）,diet B（9.5%）,diet C（12.4%）,diet D（15.1%）,or diet E（18.5）.The HDL-C content tended to increase with increasing dietary lipid levels.HDL-C levels were highest in the fish fed diet E and were significantly higher than in fish fed diets A–C（P0.05）.The LDL-C content also tended to increase at first but then decreased at higher dietary lipid levels.The LDL-C content was significantly higher in fish fed diet C than those fed diets D and E（P0.05）.TG and CHO content tended to decrease as dietary lipid levels increased.TG and CHO content were significantly lower in fish fed diets D and E than in those fed diets A-C（P0.05）.Diet had no effect on TP（P0.05）.The IgM content tended to increase then decrease with increasing dietary lipid levels.IgM levels were significantly higher in fish fed diet C than all other groups.Similarly,LZM levels increased then decreased with increasing dietary lipid levels and were significantly higher in fish fed diet C than those fed diets A,D,and E.The liver SOD,CAT, and T-AOC activity also increased then decreased with increasing dietary lipid levels.Enzyme activity was highest in fish fed diet C than all other groups.The liver MDA content increased with increasing dietary lipid levels and was higher in fish fed diets D and E than those fed diets A.C（P0.05）.Serum SOD activity also increased with increasing dietary lipid levels and was higher in fish fed diets D and E than those fed diets A.C（P0.05）.Last, serum CAT activity tended to increase but there was no difference among the groups（P0.05）.In conclusion,the adaptability of S.marmoratus to the dietary lipid levels is reflected by changes in serum biochemistry.Our data suggest the optimal dietary lipid levels（12.4%） are associated with improved immunity and antioxidant function.