饲料脂肪水平对杂交鲟幼鱼生长、饲料消化率、抗氧化水平和肌肉脂肪酸组成的影响

研究旨在探究饲料中不同脂肪水平对西伯利亚杂交鲟(Acipenser baerii Brandt♀×A. schrenckii Brandt♂)幼鱼生长、饲料消化率、血清生化指标及肌肉脂肪酸组成的影响。以鱼油为脂肪源,配制4种脂肪水平分别为5%(D05)、10%(D10)、15%(D15)和20%(D20)的等氮饲料。选用初始体重为(152.83±0.67) g的杂交鲟,随机分为4组,每组3个重复,每个重复25尾鱼。养殖周期为12周。结果显示,饲料中不同脂肪水平对杂交鲟的生长性能有显著影响(P<0.05)。其中, D15组杂交鲟幼鱼的末均重(FBW)、增重率(WGR)和特定生长率(SGR)显著高于D05、D10和D20组(P<0.05),饲料效率(FE)显著高于D05和D10组(P<0.05)。随着饲料中脂肪含量的增加,杂交鲟幼鱼脏体比(VSI)、肝体比(HSI)及肌肉、肝脏中的脂肪含量显著上升(P<0.05)。饲料中不同脂肪水平对干物质(ADCd)、蛋白质(ADCp)表观消化率无显著影响(P>0.05)。D10、D15和D20组脂肪表观消化率(ADCf)显...

EFFECTS OF DIETARY LIPID LEVELS ON GROWTH PERFORMANCE,FEED DIGESTIBILITY,ANTIOXIDANT STATUS AND FILLET FATTY ACID COMPOSITIONS OF JUVENILE HYBRID STURGEON

To investigate the effects of dietary different lipid levels on the growth performance,feed digestibility,antioxidant status,and fillet fatty acid compositions of juvenile hybrid sturgeon(Acipenser baerii Brandt ♀×A.schrenckii Brandt ♂),four isonitrogenous(42% crude protein)experimental diets were formulated with various lipid levels at 5%(D05),10%(D10),15%(D15)and 20%(D20),respectively.Hybrid sturgeon with an initial body weight of(152.83±0.67)g were randomly divided into 4 groups with 3 replicates in each group and 25 fish per replicate for a 12-week trial.The results showed that dietary different lipid levels had significant effect on the growth performance of juvenile hybrid sturgeon.Among them,final body weight(FBW),weight gain rate(WGR)and specific growth rate(SGR)in D15 group were significantly higher than those in D05,D10 and D20 groups(P<0.05).Feed efficiency(FE)in D15 group was significantly higher than that in D05 and D10 groups(P<0.05).With the enhanced dietary lipid level,viscerasomatic index(VSI),hepatosomatic index(HSI)and crude fat in fillet and liver increased significantly(P<0.05).Dietary different lipid levels had no significant effects on the apparent digestibility of dry matter(ADCd)and protein(ADCp)(P>0.05).The apparent digestibility of fat(ADCf)in D10,D15 and D20 groups was significantly higher than that in the D05 group(P<0.05).The highest apparent digestibility of energy(ADCe)was in D15 group,which was significantly higher than that in D05 and D10 groups(P<0.05).When the dietary lipid level increased from 5% to 20%,the activities of total antioxidant capacity(T-AOC),superoxide dismutase(SOD)and myeloperoxidase(MPO)were boosted(P<0.05)while glutathione peroxidase(GSH-Px)activity reduced significantly(P<0.05)in serum of juvenile hybrid sturgeon.The activities of the four liver function indicators,alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP)and lactic dehydrogenase(LDH),also showed an increasing trend(P<0.05).There was a significant positive linear correlation between the content of fillet fatty acids and the fatty acid content in the diets(R2>0.90,P<0.05).These results revealed that the optimal lipid level in the diet of juvenile hybrid sturgeon was 15%,and P/E was 23.54 mg/kJ.