不同脂肪源日粮补充维生素E对罗氏沼虾生长、免疫及肉品质的影响

本研究旨在完善罗氏沼虾（）饲料配方，降低罗氏沼虾饲料成本。研究采用3×2双因素设计，配制6组饲料，分别包含鱼油（fish oil，FO）、豆油（soybean oil，SO）、菜籽油（rapeseed oil，RO）三种脂肪源；200 mg/kg（200VE）和600 mg/kg（600VE）两个维生素E（VE）水平。养殖实验在温室水泥池中进行，每个处理3个重复，养殖期8周，每天定点定量投喂3次。结果显示，相对于FO组，SO和RO组增重率、特定生长率显著升高，饵料系数显著下降（>0.05）。对于血淋巴抗氧化指标，在相同VE水平下，FO组血淋巴总抗氧化能力（T-AOC）和超氧化物歧化酶（SOD）活性均显著低于SO和RO组，谷胱甘肽过氧化物酶（GPX）活性均显著高于SO和RO组（<0.05）。在相同脂肪源下，600VE可显著提高FO组T-AOC活性，RO组GPX活性以及SO和RO组SOD活性（>0.05）。对于血淋巴生理生化指标，谷草转氨酶（AST）、总蛋白（TP）、白蛋白（ALB）和甘油三酯（TC）受日粮影响显著（<0.05）。此外，日粮脂肪源和VE水平对肉质也有显著影响。其中，SO组肌肉鲜度和滋味强度较高；RO组鱼腥味较低；FO组肌肉亮度较高，气味强度较低。在200 mg/kg VE水平下，FO组肌肉硬度、胶黏性、耐咀性、黏性和回复性显著高于植物油组（<0.05），而对肌肉蒸煮损失和滴水损失无显著影响（>0.05）。上述结果表明，相对于鱼油，豆油和菜籽油等植物油是罗氏沼虾更优质的脂肪源，VE在以鱼油为单一脂肪源的饲料中有一定的促生长和缓解应激的作用，且脂肪源和VE均显著影响肌肉品质。本研究结果将为降低鱼油在罗氏沼虾饲料中的使用提供数据支持。

Effect of various dietary lipid sources combined with vitamin E supplementation on growth performance, immunity, and flesh quality in Macrobrachium rosenbergii

The purpose of this study was to investigate the effect of various sources of dietary lipids with vitamin E (VE) supplementation as feed additives on growth, flesh quality, and immunity in . A 3×2 factorial design with total 6 feed groups was implemented, comprising three different lipid sourcesfish oil (FO), soybean oil (SO), and rapeseed oil (RO)] and two levels of dietary VE200 mg/kg (200VE) and 600 mg/kg (600VE)]. The feeding trial was conducted in a cement pond inside a greenhouse. Prawns were fed thrice daily for 8 weeks. Results demonstrated that rate of weight gain and specific growth rate significantly increased in the SO and RO groups, compared to the FO group, while the feed coefficient significantly decreased (<0.05). VE had no significant effect on growth performance and feed utilization. We measured antioxidant parameters in lymph. Among prawns receiving the same amount of VE, both total anti-oxidative capacity (T-AOC) and superoxide dismutase (SOD) activity were significantly lower, while glutathione peroxidase (GPx) activity was significantly higher (<0.05) in the FO group than in the SO and RO groups. Malondialdehyde (MDA) content in the SO group was significantly lower (<0.05) than in the FO and RO groups. Among prawns receiving the same lipid source, supplementation with 600VE was found to significantly increase T-AOC activity in the FO group, GPX activity in the RO group, and SOD activity in both SO and RO groups (<0.05). Nevertheless, dietary VE level had no significant effect on MDA content of lymph. Physiological and biochemical indices of lymph, including aspartate aminotransferase (AST), total protein (TP), albumin (ALB) and triglycerides (TC) were significantly affected by diet type (<0.05); AST and ALB were significantly affected by ammonia nitrogen stress (<0.05). Further, dietary lipid sources and VE levels also had significant effects on flesh quality. Flesh was fresher and tasted better in the SO group; flesh in the RO group had less fishy odor, while flesh in the FO group had more color with less odor. At the 200 mg/kg VE level, flesh hardness, adhesiveness, cohesiveness, gumminess, chewiness, and resilience were significantly higher in the FO group compared to the SO and RO groups (<0.05); flesh cooking loss in the RO group was significantly higher than that in the other groups (<0.05). At the 600 mg/kg VE level, flesh tenderness and juiciness significantly increased, while there was no significant effect on flesh cooking loss and drip loss. Our results suggest that compared to fish oil, vegetable oils such as soybean oil and rapeseed oil are better sources of dietary lipids for . VE has a growth promoting and stress alleviating effect when added to feeds with fish oil as a single lipid source. In addition, both lipid source and VE level significantly affect the flesh quality.