背景:确定具有高营养价值的替代可持续饲料来源对于对环境和社会负责的水产养殖的未来至关重要。在这方面,微藻已被证明对鱼类健康有积极影响,这压倒了我们对这项研究的兴趣。
方法:Pediastrumboryanum(P.boryanum)以0、0.75和1.5mg/kg的浓度掺入尼罗罗非鱼饲料中,作为控制,PbExt0.75和PbExt1.5组以评估其对生长和生化指标的影响,氧化剂/抗氧化剂活性,免疫和应激相关基因表达,和肠道形态。
结果:8周后,饲喂P.boryanum补充饲料的鱼表现出最终重量的显着增加,长度,条件因子,体重增加,和特定的增长率,而脾体指数(SSI)和肝细胞指数(HSI)与对照组相比没有显着差异。膳食P.boryanum补充也提高了IgM水平和溶菌酶活性,对肝功能酶(丙氨酸转氨酶/ALT和天冬氨酸转氨酶/AST)或蛋白质状态(总蛋白和白蛋白)的标志物没有显着影响。此外,P.boryanum的添加增加了超氧化物歧化酶(SOD)的活性,过氧化氢酶(CAT),和还原型谷胱甘肽(GSH)酶,突出了它的抗氧化潜力,而丙二醛(MDA)浓度在各组之间没有显着差异。基因表达分析显示肿瘤坏死因子-α(TNF-α),白细胞介素-10(IL-10),和转化生长因子-β1(TGF-β1)表达显着增加,在饲喂含P.boryanum饲料组,肝热休克蛋白70(HSP70)mRNA表达无明显差异。组织病理学检查显示,补充P.boryanum对肝脏没有不良影响,脾,脾或肠组织。绒毛高度和绒毛表面积显着增加。提示改善肠道完整性和营养吸收。
结论:膳食中补充P.boryanum可能会提高生长性能,免疫反应,抗氧化状态,尼罗罗非鱼的肠道健康,使其成为可持续水产养殖的有希望的候选者。
BACKGROUND: Identifying alternative sustainable feed sources with high nutritional values is crucial for the future of environmentally and socially responsible aquaculture. In this regard, microalgae have been proven to have positive effects on fish health, which overwhelmed our interest in this study.
METHODS: Pediastrum boryanum (P. boryanum) was incorporated into Nile tilapia feed at concentrations of 0, 0.75, and 1.5 mg/kg, as control, PbExt0.75, and PbExt1.5 groups to assess its effects on growth and biochemical indices, oxidant/antioxidant activities, immune and stress-related gene expression, and intestinal morphology.
RESULTS: After 8 weeks, fish fed P. boryanum supplemented feed exhibited significant increases in final weight, length, condition factor, body weight gain, and specific growth rate, while the spleen-somatic index (SSI) and hepatosomatic index (HSI) showed no significant differences compared to the control group. Dietary P. boryanum supplementation also enhanced IgM levels and lysozyme activity, along with no marked effect on markers of liver function enzymes (alanine aminotransferase/ALT and aspartate aminotransferase/AST) or protein status (total protein and albumin). Furthermore, P. boryanum addition increased the activity of superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) enzymes, highlighting its antioxidant potential, whereas malondialdehyde (MDA) concentrations showed no significant differences among the groups. Gene expression analysis revealed that tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), and transforming growth factor-β1 (TGF-β1) expression notably increased in groups fed P. boryanum containing feed, while no significant difference was observed in hepatic Heat Shock Protein 70 (HSP70) mRNA expression. Histopathological examination revealed no adverse effects of P. boryanum supplementation on the liver, spleen, or intestinal tissues. Villous height and villous surface area were notably increased in the high P. boryanum supplementation group, suggesting improved intestinal integrity and nutrient absorption.
CONCLUSIONS: Dietary P. boryanum supplementation can potentially improve growth performance, immune response, antioxidant status, and intestinal health of Nile tilapia, making it a promising candidate for sustainable aquaculture.