本研究旨在探讨短期饲喂高脂饲料对珍珠龙胆石斑鱼(Epinephelus fuscoguttatus ♀×Epinephelus lanceolatus ♂) 生长性能和抗氧化能力所产生的影响, 以便于预估高脂饲料对石斑鱼生长可能产生的负面影响。在粗蛋白水平为 48%的基础上分别配制脂肪水平为 8% (EE8)、10% (EE10)、12% (EE12)、14% (EE14)、16% (EE16)、18% (EE18) 和 20% (EE20)的 7 组等氮饲料, 饲喂初均重为(13.70±0.01) g 的珍珠龙胆石斑鱼 4 周。实验结果表明, 随着饲料粗脂肪水平的提升, 增重率(WGR)和存活率(SR)无显著性变化(P＞0.05), EE14~EE20 组饲料系数(FCR)显著降低(P＜0.05), 而脏体比(VSI)显著增大(P＜0.05), 饲料粗脂肪超过 16%后蛋白质效率(PER)显著上升(P＜0.05)。EE14~EE20 组腹肌粗脂肪(AMEEC)显著升高(P＜0.05), EE16~EE20 组的肝体比(HSI)显著增大(P＜0.05)。与 EE12 组相比, EE8、EE10、 EE18 和 EE20 组的总胆固醇(T-CHO)显著升高(P＜0.05), EE16~EE20 组谷胱甘肽过氧化物酶(GSH-PX)活性显著下降 (P＜0.05), EE20 组丙二醛(MDA)含量显著上升(P＜0.05), EE8、EE16~EE20 组的肝脏细胞空泡化面积和脂滴量显著增加(P＜0.05)。脂肪合成基因 g6pd、6gpd 和 me 的相对表达量在 EE20 组显著上升(P＜0.05), 脂肪分解基因 cpt-1、pparα 相对表达量在 EE16~EE20 组显著上升(P＜0.05)。研究结果表明, 饲料粗脂肪超过 16.77%时, 会造成珍珠龙胆鱼肝脏脂肪沉积, 降低肝脏抗氧化能力, 使肝脏健康受损。

The aim of this experiment was to investigate the effects of high-fat diets on the short-term growth performance and antioxidant capacity of pearl grouper to help formulators and farmers anticipate the possible negative effects of high-fat diets on grouper growth and take effective measures in the formulation and feeding schedule of high-fat diets. Seven groups of isonitrogenous diets with fat levels of 8% (EE8), 10% (EE10), 12% (EE12), 14% (EE14), 16% (EE16), 18% (EE18), and 20% (EE20) were fed to pearl grouper (initial mean weight: 13.70±0.01g) for 4 weeks with a crude protein level of 48%. The experimental results showed no significant change in weight gain rate (WGR) and survival rate (SR) as the level of dietary ether extract increased (P＞0.05), while the feed intake was significantly lower in the EE14-EE20 group (P＜0.05); further, the viscerosomatic index (VSI) and protein efficiency ratio (PER) increased significantly (P＜0.05) after the dietary ether extract exceeded 16%. The EE14-EE20 group had a significantly higher abdominal muscle ether extract (AMEEC) (P＜0.05), and the EE16-EE20 group had a significantly greater hepatosomatic index (HSI) (P＜0.05). Compared to the EE12 group, total cholesterol (T-CHO) was significantly higher in the EE8, EE10, EE18, and EE20 groups (P＜0.05); glutathione peroxidase (GSH-PX) activity was significantly lower in the EE16-EE20 group (P＜0.05); malondialdehyde (MDA) content was significantly higher in the EE20 group (P＜0.05); and vacuolated area and hepatocytes in the EE8 and EE16-EE20 groups’ lipid droplet amount were significantly increased (P＜0.05). The relative expression of the lipid synthesis genes g6pd, 6gpd, and me was significantly increased in the EE20 group (P＜0.05), and the lipolytic genes cpt-1 and pparα were significantly increased in the EE16-EE20 group (P＜0.05). The results have shown that dietary ether extract above 16.77% causes fatty deposits in the liver of pearl amberjack, reducing the liver’s antioxidant capacity and impairing liver health.

S917

广东省基础与应用基础研究基金项目(2021A1515010634).