氧化鱼油对黄颡鱼幼鱼肠道健康的影响及精氨酸的干预作用

为研究饲料中添加氧化鱼油对黄颡鱼幼鱼肠道免疫、抗氧化和其他功能指标、组织结构的影响及添加精氨酸对其的干预作用,采用2×3设计方式,在饲料中分别添加新鲜鱼油(FF)∶氧化鱼油(OF)按照(m/m)2.5∶0、1.5∶1.0和0.5∶2.0的比例配制3种基础饲料(FF,OF1,OF2),在基础饲料中分别添加0.48%精氨酸(Arg)盐酸盐配制3种精氨酸饲料(FFA,OFA1,OFA2),选取初始体质量为(4.41±0.05)g的黄颡鱼600尾,随机分为6组,每组4个重复,分别投喂6种实验饲料,饲养56 d。结果显示,在OF2组中,黄颡鱼肠道酸性磷酸酶(ACP)、碱性磷酸酶(AKP)活性和白细胞介素-6(IL-6)含量显著升高;与OF2组相比,OFA2组AKP活性和IL-6含量均显著下降。在FF、OF1、OF2三组中,肠道超氧化物歧化酶(SOD)活性呈下降趋势,谷胱甘肽过氧化物酶(GSH-PX)和过氧化氢酶(CAT)活性呈现上升趋势,总抗氧化能力(T-AOC)呈现先下降后上升的趋势,但差异均不显著;在OF2组中,丙二醛(MDA)含量显著升高;添加精氨酸后,除SOD活性有显著升高外,其他抗氧化指标的组间均无显著性差异。双因素方差分析显示,精氨酸对黄颡鱼肠道CAT活性的影响达到显著水平,饲料中氧化鱼油和精氨酸对黄颡鱼肠道GSH-PX活性的影响存在交互作用。在FF、OF1、OF2三组中,肠道二胺氧化酶(DAO)活性呈现下降趋势,一氧化氮合酶(i NOS)活性呈现上升趋势,但差异均不显著;与OF2组相比,OFA2组的DAO和i NOS活性分别显著升高和下降;双因素方差分析显示,精氨酸(Arg)对黄颡鱼肠道DAO、i NOS活性的影响分别达到显著水平。在OF1组中,肠道皱壁高度、肌层厚度和杯状细胞数量均明显升高;与OF2组相比,OFA2组皱壁高度和杯状细胞数量明显升高;与FF组相比,FFA组肌层厚度明显增加。双因素方差分析显示,氧化鱼油对黄颡鱼肠道皱壁高度的影响达到显著水平。研究表明,在饲料中添加一定水平的氧化鱼油会抑制黄颡鱼幼鱼肠道免疫及抗氧化指标,损伤肠道组织结构,但添加一定量的精氨酸可以缓解氧化鱼油对黄颡鱼幼鱼肠道免疫、抗氧化和组织结构的抑制作用。

Influence of Oxidized Fish Oil on the Intestinal Health of Yellow Catfish (Pelteobagrus fulvidraco) and the Use of Arginine as an Intervention Measure

This experiment was conducted to investigate the influence of dietary oxidized fish oil (OF) and the intervention of Arginine (Arg) on the intestinal health of juvenile yellow catfish. A total of 600 healthy yellow catfish (Pelteobagrus fulvidraco) with an initial body weight of (4.41±0.05) g were randomly divided into 6 groups with 4 replicates of 25 fish. During 56 d feeding trial, the fish were fed respectively six diets containing 2.5% fresh fish oil (FF), 1.5% FF+1.0% OF (OF1), 0.5% FF+2.0% OF (OF2), 2.5% FF+0.48% Arg (FFA), 1.5% FF+1.0% OF+0.48% Arg (OFA1), 0.5% FF+2.0% OF +0.48% Arg (OFA2). The results showed that the ACP, AKP activities and IL-6 content in intestine of yellow catfish were significantly higher in OF2 group. As for addition of arginine to the oxidized fish oil diets, the AKP activity and IL-6 content in intestine of yellow catfish were significantly lower in OFA2 group. The SOD activity in intestine of yellow catfish showed a downward trend and the GSH-PX and CAT activities showed a reversed trend, but there were no significant differences among FF, OF1 and OF2 groups. The SOD activity was significantly higher in OFA2 group. The MDA content in intestine of yellow catfish were significantly higher in OF2 group. Dietary oxidized fish oil and arginine had a significant interaction on the GSH-PX activity in intestine of yellow catfish. The CAT activity in intestine was significantly decreased by the arginine. The DAO activity in intestine of yellow catfish showed a downward trend and the iNOS showed an upward trend, but there was no significant difference among FF, OF1 and OF2 groups. The DAO activity significantly increased and iNOS significantly decreased in OFA2 group. The arginine had a significant impact on the DAO and iNOS activities in intestine of yellow catfish. The height of folds, the thickness of muscles and the number of goblet cells in foregut increased in OF1 group. In comparison with OF2 group, the height of folds and the number of goblet cells in foregut increased in the OFA2 group. Oxidized fish oil showed a significant influence on the height of folds. The results suggest that dietary oxidized fish oil would reduce the intestinal immune and total antioxidant capacity, and damage the structure in foregut of juvenile yellow catfish, but arginine supplementation can alleviate the inhibition induced by oxidized fish oil for intestinal immune, antioxidant capacity and tissue structure.