甘草次酸对斑点叉尾鮰免疫应激下血浆抗氧化酶和免疫指标的影响

为探讨斑点叉尾鮰免疫应激状态下血浆抗氧化酶和免疫指标的变化,并研究甘草次酸对斑点叉尾鮰免疫应激的调控机制,实验设计两组,每组6个重复:1)对照组,饲喂基础饲料;2)GA组,饲喂含0.15 g/kg甘草次酸饲料,养殖8周后,腹腔注射大肠杆菌脂多糖(LPS),分别在注射后0、3、6、12、24、48 h采集血液和肝脏组织,进行红细胞、白细胞计数,分离血浆后检测血浆史质醇、溶菌酶、ACH50、谷草转氨酶、谷丙转氨酶、碱性磷酸酶活性,肝脏匀浆液检测SOD、MDA和CAT抗氧化酶活性。结果显示,在腹腔注射LPS后,血浆溶菌酶、史质醇、谷草转氨酶、谷丙转氨酶、ACH50、SOD均呈现先升高后下降的趋势,白细胞计数、血浆CAT呈现先下降后升高的趋势;饲料中添加0.15 g/kg甘草次酸显著抑制了各指标变化,缩短了由LPS诱导产生各指标变化的恢复时间。研究表明,腹腔注射LPS使斑点叉尾鮰产生免疫应激,并在注射后6~12 h达到顶峰;饲料中添加0.15 g/kg甘草次酸可以有效抑制由LPS诱导的免疫应激反应。     

酵母免疫多糖对受免斑点叉尾(鮰)免疫应答的增强作用

在饲料中添加定量的酵母免疫多糖,投喂注射接种了福尔马林灭活的嗜水气单胞菌(Aeromonas hydrophila)菌苗的斑点叉尾(鮰)(Ictalurus punctatus),28 d后通过测定供试鱼的增重量、血清中凝集抗体效价、溶菌酶活性、谷丙转氨酶活性(SGPT)、血清总蛋白含量、白细胞吞噬活性以及活菌攻毒后的免疫保护率(RPS),探讨了酵母免疫多糖对受免斑点叉尾(鮰) 免疫应答的增强作用.结果表明,用添加200.0 mg/(kg·d)酵母免疫多糖的饲料投喂受免斑点叉尾(鮰),不仅可以使受免斑点叉尾(鮰) 对灭活嗜水气单胞菌的免疫应答水平提高,增强抵抗嗜水气单胞菌人工感染的能力,而且还具有一定的促进生长和改善肝功能的作用.     

酵母免疫多糖对受免斑点叉尾免疫应答的增强作用

在饲料中添加定量的酵母免疫多糖,投喂注射接种了福尔马林灭活的嗜水气单胞菌(Aeromonas hydrophila)菌苗的斑点叉尾(Ictalurus punctatus),28 d后通过测定供试鱼的增重量、血清中凝集抗体效价、溶菌酶活性、谷丙转氨酶活性(SGPT)、血清总蛋白含量、白细胞吞噬活性以及活菌攻毒后的免疫保护率(RPS),探讨了酵母免疫多糖对受免斑点叉尾免疫应答的增强作用。结果表明,用添加200.0 mg/(kg.d)酵母免疫多糖的饲料投喂受免斑点叉尾,不仅可以使受免斑点叉尾对灭活嗜水气单胞菌的免疫应答水平提高,增强抵抗嗜水气单胞菌人工感染的能力,而且还具有一定的促进生长和改善肝功能的作用。     

酵母免疫多糖对受免斑点叉尾鲴免疫应答的增强作用

在饲料中添加定量的酵母免疫多糖，投喂注射接种了福尔马林灭活的嗜水气单胞菌（Aeromonas hydrophila）菌苗的斑点叉尾鲴（Ictalurus punctatus），28d后通过测定供试鱼的增重量、血清中凝集抗体效价、溶菌酶活性、谷丙转氨酶活性（SGPT）、血清总蛋白含量、白细胞吞噬活性以及活菌攻毒后的免疫保护率（RPS），探讨了酵母免疫多糖对受免斑点又尾鲴免疫应答的增强作用。结果表明，用添加200．0mg／（kg·d）酵母免疫多糖的饲料投喂受免斑点叉尾鲴，不仅可以使受免斑点叉尾鲴对灭活嗜水气单胞菌的免疫应答水平提高，增强抵抗嗜水气单胞菌人工感染的能力，而且还具有一定的促进生长和改善肝功能的作用。     

鮰爱德华氏菌灭活疫苗免疫斑点叉尾鮰后外周血免疫指标的变化

在水温(25±1)℃下,给平均体质量(80±5)g的斑点叉尾鮰Ictalurus punctatus腹腔注射福尔马林灭活的鮰爱德华氏菌(Formalin-killed Edwardsiella ictaluri,FKE)后,第2、4、6、8、14、21,和28d测定外周血液免疫指标,并在免疫后第28天进行攻毒试验。结果显示:注射鮰爱德华氏菌灭活菌苗后,斑点叉尾鮰外周血红细胞和白细胞数量显著升高,白细胞分类组成变化显著,吞噬细胞的吞噬活性与凝集抗体效价显著上升。第4d免疫组红细胞和白细胞达峰值2.52×106/μL和4.67×105/μL,极显著高于对照组(P<0.01);单核细胞、中性粒细胞、吞噬细胞分类百分比和吞噬指数均在第4d达到峰值,分别为22.3%、5.67%、39.3%和4.33,极显著高于对照组(P<0.01);淋巴细胞分类百分比、凝集抗体效价在第21d达到峰值,分别为54.33%和1:341.33,极显著高于对照组(P<0.01)。攻毒试验结果表明:免疫组相对免疫保护率为64.3%。福尔马林灭活的鮰爱德华氏菌免疫后,斑点叉尾鮰获得较强的抗鮰爱德华氏菌感染保护能力,为进一步研究斑点叉尾鮰肠道败血症的免疫奠定基础。     

斑点叉尾鮰对气单胞菌抗原接种免疫效果观察及间接ELISA检测分析

通过用分离于斑点叉尾鮰病例的嗜水气单胞菌制备成免疫原,经纯化并制备ELISA诊断试剂。经腹腔接种健康斑点叉尾鮰,同时在免疫接种后50d,70d,90d,做相应气单胞菌的人工感染试验和ELISA检测试验。结果表明,斑点叉尾鮰对嗜水气单胞菌抗原免疫可以产生良好的免疫抗体应答,其保护效果与抗体水平有一定的相关性,经免疫后的鱼对相应菌株的感染具有一定的免疫保护作用。     

血根碱对LPS诱导后黄鳝免疫应激及肠道炎症相关基因表达的影响

为探讨血根碱是否具有缓解黄鳝(Monopterus albus)由脂多糖(LPS)诱导后引起的免疫应激及炎症反应作用,本实验设置对照组(基础饲料)和实验组(基础饲料+750μg/kg血根碱),每组3个重复,养殖实验持续8周,结束后每个重复随机取30尾规格一致的黄鳝经腹腔注射大肠杆菌脂多糖(LPS),在注射前0 h和注射后3 h、6 h、12 h、24 h和48 h进行采样。结果显示,在0 h时,实验组肝脏中超氧化物歧化酶(SOD)活力显著高于对照组(P0.05),其余指标均无显著性差异(P0.05);血清中葡萄糖(GLU)、皮质醇(COR)、IgM、C4、碱性磷酸酶(AKP)、谷草转氨酶(GOT)、谷丙转氨酶(GPT)和肝脏中SOD在腹腔注射LPS后均呈先上升后下降的趋势,并在3 h或6 h达到峰值,肝脏中丙二醛(MDA)的变化趋势与其相反;与对照组相比,实验组血清中AKP、IgM、C4的含量和肝脏中SOD活力在注射LPS后上升幅度更大,GLU和COR的含量上升幅度慢,并且GLU、COR、AKP、IgM、C4、GOT和GPT恢复至正常水平速度更快。肠道中炎症相关基因IL-1β、IL-10、IL-12β、IL-15、TGF-β1和TGF-β2表达量在腹腔注射LPS后呈先上升后下降的趋势,并在6 h或12 h达到峰值;与对照组相比,实验组下调了IL-1β和IL-12β基因表达量,上调了IL-10、IL-15、TGF-β1、TGF-β2和TGF-β3基因表达量。综上所述,在本研究条件下,腹腔注射LPS诱导黄鳝产生了免疫应激及炎症反应,在3～6 h时出现高峰,而饲料中添加750μg/kg血根碱能够有效改善黄鳝由LPS诱导产生的免疫应激及炎症反应。     

喹烯酮对建鲤和斑点叉尾鮰生长性能和抗缺氧能力的影响

在池塘养殖条件下,饲料中添加3个不同含量(50、75和100 mg/kg)的喹烯酮来饲养建鲤(Cyprinus carpio var.Jian)和斑点叉尾鮰(Ietalurus Punetaus),养殖周期为60 d,研究喹烯酮对建鲤和斑点叉尾鮰生长性能和抗缺氧能力的影响。结果表明:与不添加喹烯酮的对照组相比,添加喹烯酮的实验组中建鲤和斑点叉尾鮰生长速度加快,死亡率降低,饲料系数下降。当饲料中添加喹烯酮的剂量为75 mg/kg时,其对建鲤和斑点叉尾鮰的生长效率提高最佳(P0.05),饲料系数最低,成活率最高。在75 mg/kg的喹烯酮添加量下,建鲤和斑点叉尾鮰的抗缺氧能力、血细胞和血红蛋白量均有提高,但与对照组相比,差异均不显著(P0.05)。饲料中添加喹烯酮对建鲤和斑点叉尾鮰生长性能的作用呈现非剂量依赖性,而且添加75 mg/kg喹烯酮对其抗缺氧能力影响不显著(P0.05)。研究表明,建鲤和斑点叉尾鮰养殖中喹烯酮的最适用量为75 mg/kg。     

在南宁用小体积高密度网箱和豆粕型饲料养殖斑点叉尾(鱼回)试验

本试验利用美国大豆协会的小体积高密度网箱养殖模式和豆粕型饲料在广西壮族自治区南宁市邕江进行了斑点叉尾鮰从鱼种至成鱼的养殖示范试验。斑点叉尾鮰鱼种放养在5个1m3的网箱中,放养密度为400尾/m3。经166天饲养,斑点叉尾鮰从91g/尾长到了658g/尾。试验所用饲料为蛋白质32％的全植物性蛋白源豆粕饲料,平均饲料系数为1.76:1。养殖斑点叉尾鮰的平均毛产量为185kg/m3,成活率70％。该养殖试验受到了洪水、高温和河水中高泥沙含量的影响。     

甘露寡糖对斑点叉尾鮰成活率及生长的影响

在水库中选用8个网箱进行斑点叉尾鮰的养殖试验,网箱分为试验箱和对照箱2个组,每组设4个平行.在试验组的斑点叉尾鮰饲料中添加甘露寡糖进行投喂,甘露寡糖添加量为鱼体重的0.15‰,对照组不添加,试验时间60 d.结果表明,试验组斑点叉尾鮰成活率为94.51%,对照组为87.01%,高出7.5个百分点.随着投喂时间的延长,试验组斑点叉尾鮰的死亡率呈明显下降趋势,至试验结束时的第55～60天,死亡率比对照组的同一时间段下降了10倍;试验组斑点叉尾鮰体重的增加比对照组快16.5%,差异极显著(P<0.01).     

Beneficial effects of thyme (Thymus vulgaris) extract on oxytetracycline‐induced stress response,immunosuppression, oxidative stress and enzymatic changes in rainbow trout (Oncorhynchus mykiss)

The aim of the present study was to investigate the effects of thyme extract (TE) and oxytetracycline (OTC) on rainbow trout (Oncorhynchus mykiss) stress response, immune parameters, oxidative stress and enzymatic changes. The fish were assigned into eight treatments receiving diets with OTC (0 and 2.5 g/kg) and TE (0, 5, 10 and 20 g/kg) for 2 weeks. Thereafter, serum characteristics and gut oxidative status were evaluated. OTC significantly increased serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, and cortisol and glucose levels; however, TE significantly suppressed these changes. OTC significantly decreased, but TE significantly increased gut catalase (CAT) and glutathione peroxidase (GPx) activities. OTC significantly decreased gut superoxide dismutase (SOD) and increased gut glutathione‐s‐transferase (GST) activities, malondialdehyde (MDA) content and blood monocyte percentage; TE significantly mitigated these changes. TE significantly increased serum total protein, total Ig, lysozyme and ACH50, and blood WBC; however, OTC significantly decreased serum lysozyme and ACH50 activities and blood WBC and neutrophil percentage. In conclusion, OTC administration causes immunosuppression, which might be related to deterioration of fish health. TE augments trout innate immune and antioxidant status and is capable to counteract OTC‐induced health and immune deterioration.     

Effect of dietary eucalyptol on stress markers,enzyme activities and immune indicators in serum and haematological characteristics of common carp (Cyprinus carpio) exposed to toxic concentration of ambient copper

In the present study, protective effects of dietary eucalyptol were investigated against copper toxicity in common carp (Cyprinus carpio). The fish were fed with diets supplemented with 0 (control), 0.5% and 1% eucalyptol for 14 days before exposure to 0.25 mg/L ambient copper for 7 days. Blood samples were taken from the fish before and 1, 3 and 7 days after copper challenge. Before copper challenge, eucalyptol significantly decrease serum aspartate aminotransferase (AST) activity, but increase blood WBC, RBC, hematocrit and haemoglobin, serum lysozyme, total immunoglobulin (Ig) compared with the control. Copper exposure led to stress, tissue damage and immunosuppression. After the copper challenge, significant elevation in serum cortisol, glucose, alanine aminotransferase (ALT) and AST, but decrease in blood RBC and WBC, and serum lysozyme, complement (ACH50) and total immunoglobulin (Ig) was observed. Eucalyptol administration significantly mitigated the increase in serum cortisol, glucose, ALT and AST, and decrease in WBC, ACH50, lysozyme and total Ig. Dietary 1% eucalyptol had significantly higher protective effects than 0.5% in the case of serum AST, lysozyme, total Ig and ACH50. In conclusion, eucalyptol has beneficial health effects on common carp and enables to mitigate copper‐induced stress, tissue damage, and immunosuppression. Eucalyptol at the dietary 1% level is recommended to protect common carp against adverse effects of copper toxicity.     

胆碱对高脂胁迫的团头鲂肝脏抗氧化、组织结构和免疫力的影响

以初始体质量(42.20±0.34)g团头鲂为研究对象,研究饲料中添加胆碱对高脂胁迫团头鲂肝脏抗氧化、组织结构和免疫力的影响。实验采用2×2因子设计方法,共配置2个脂肪水平(5%和15%)和2个胆碱水平(1200和2200 mg/kg)的等氮饲料4组。养殖实验在室内循环水系统中进行,养殖周期为8周。养殖实验结束后进行血液和肝脏生化指标、肝脏抗氧化指标和非特异性免疫指标等的检测分析,以及观察肝细胞的超微结构变化。结果显示,当饲料中添加1200 mg/kg胆碱时,随着脂肪水平的升高,团头鲂肝脏脂肪含量和甘油三酯浓度显著增加,而血浆中谷草转氨酶(AST)和谷丙转氨酶(ALT)活性则显著上升;肝脏中丙二醛(MDA)含量、总超氧化物歧化酶(t-SOD)活性、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GPX)活性等显著升高;血液中白细胞数、溶菌酶活性、总蛋白和球蛋白水平以及还原型谷胱甘肽(GSH)活性显著降低;超微结构观察到肝细胞中存在大量脂滴,伴随着细胞核变性、核膜残缺、线粒体水肿等异常现象。这些结果表明高脂日粮不仅导致肝细胞的结构和功能的损伤,而且造成肝脏氧化应激和机体免疫力的下降。在高脂饲料(15%脂肪)中添加2200 mg/kg胆碱,可显著降低肝脏脂肪含量、血浆谷草转氨酶(AST)和谷丙转氨酶(ALT)活性,显著降低肝脏丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,并显著提高白细胞数和球蛋白水平以及还原型谷胱甘肽(GSH)活性,同时肝细胞形态及细胞器结构也趋于正常。研究表明,添加适量胆碱能够减少肝脏脂肪沉积,维持肝脏结构和功能的正常,并增强团头鲂抗氧化能力和机体免疫力,继而保持鱼体的健康。     

Effects of dietary tryptophan levels and fish stocking density on immunological and antioxidant responses and bactericidal activity against Aeromonas hydrophila in rainbow trout (Oncorhynchus mykiss)

Rainbow trout (Oncorhynchus mykiss) was reared under low (LD) and high (HD) stocking densities for 70 days, during which they were fed with diets supplemented with 0, 5 and 10 g tryptophan (Trp) per kg. At the end of the experiment, there were significant interaction effects of the stocking density and Trp levels on plasma Trp, globulin, lysozyme, catalase (CAT), malondialdehyde (MDA), and bactericidal activity and blood leucocyte count. However, there was no difference in plasma complement (ACH50), total immunoglobulin (Ig), total antioxidant capacity (TAC), superoxide dismutase (SOD) and blood differential leucocyte count. Trp at 5 g per kg diet significantly increased lysozyme and bactericidal activity, and decreased MDA under both the LD and HD conditions. Moreover, it significantly increased plasma CAT and blood leucocyte under the LD and HD conditions respectively. Trp at 10 g per kg diet significantly increased blood leucocyte and plasma bactericidal activity under the LD condition, but significantly decreased plasma globulin and bactericidal activity under the HD condition. In conclusion, the present results showed that the effects of Trp on immune and antioxidant systems depend on Trp levels and stressful conditions. As 5 g Trp per kg diet is beneficial for rainbow trout well‐being under both the LD and HD conditions, higher level of Trp (10 g/kg) is not beneficial and even causes some negative effects under the HD condition.     

Dietary ginger administration attenuates oxidative stress and immunosuppression caused by oxytetracycline in rainbow trout (Oncorhynchus mykiss)

In the present study, potential ameliorative effects of dietary ginger (GN) were investigated on antioxidant and immune responses of rainbow trout (Oncorhynchus mykiss) during oxytetracycline (OX) administration. As a 2 × 3 factorial design, the fish were orally treated with OX (a daily dose of 100 mg/kg) and GN (either 10 or 20 g/kg diet) for 10 days. Then, blood samples were taken from each treatment to monitor plasma lysozyme, complement (ACH50), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione‐S‐transferase (GST) activities, and reduced glutathione (GSH), malondialdehyde (MDA), total immunoglobulin (Ig) and globulin levels. OX treatment significantly decreased SOD (30%), GPx, (10%) and lysozyme (23%) activities, and GSH (19%) levels; however, it increased GST (16%) activity and MDA (28%) levels. Ten grams GN per kg levels significantly decreased SOD (35%), CAT (13%), GST (20%) and MDA (30%), but increased GSH (30%), lysozyme (48%) and globulin (16%). Twenty grams GN per kg diet significantly decreased SOD (26%) and MDA (17%), but increased lysozyme (31%) levels. Interaction effects of dietary GN and OX were observed on plasma MDA and GPx levels, as 10 g GN per kg diet prevented the OTC‐induced changes in these parameters. Moreover, 20 g GN per kg diet prevented the OX‐induced change in GPx activity and mitigated the MDA elevation by 20%. It is concluded that GN administration at 10 g/kg diet is beneficial in mitigating oxidative stress and immunosuppression of rainbow trout during OX administration.     

鱼腥草对无乳链球菌引起吉富罗非鱼肝脏损伤的修复作用

为探讨池塘种植鱼腥草对无乳链球菌引起吉富罗非鱼肝脏损伤的修复作用,在养殖池塘中分别种植0%(对照组)、5%、10%和15%池塘面积的鱼腥草,养殖90 d后进行无乳链球菌人工感染,分别在感染后0、24、48和72 h采集吉富罗非鱼肝脏,进行肝脏生化、抗氧化性能、组织病理和热休克蛋白70基因(HSP 70)表达研究。结果显示,感染后48和72 h对照组肝脏谷丙转氨酶(ALT)和谷草转氨酶(AST)活性最高,种植鱼腥草各组吉富罗非鱼肝脏ALT活性在感染前后均无显著性变化,感染后72 h,10%组吉富罗非鱼肝脏AST活性已恢复到感染前水平。抗氧化指标显示,种植鱼腥草能减缓链球菌感染引起吉富罗非鱼肝脏总抗氧化能力(T-AOC)下降,显著提高肝脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)和一氧化氮合酶(NOS)等抗氧化酶的活性,增加自由基清除能力,减少脂质过氧化丙二醛(MDA)的产生。组织病理学观察显示,对照组吉富罗非鱼感染后48 h肝窦明显淤血,肝索排列紊乱,肝细胞脂肪变性,而各种植鱼腥草组吉富罗非鱼在感染后仅表现为肝细胞明显嗜酸,肝窦轻度扩张。定量PCR结果显示,每组吉富罗非鱼肝脏HSP 70表达量在感染后都显著升高,感染后各时间点对照组吉富罗非鱼肝脏的HSP 70表达量均显著高于鱼腥草种植组。研究表明,种植鱼腥草能显著改善链球菌感染所造成的吉富罗非鱼肝脏AST和ALT上升,提高抗氧化应激能力,减轻链球菌感染引起的病理损伤;吉富罗非鱼通过肝脏HSP 70高表达促进受损蛋白质的早期修复与降解,种植鱼腥草具有抗炎作用和提高鱼体抵御病原菌的能力。     

Effects of dietary turmeric administration on stress,immune, antioxidant and inflammatory responses of common carp (Cyprinus carpio) during copper exposure

The present study assessed the effects of dietary turmeric on Cyprinus carpio resistance and responses to copper exposure. First, the fish were assigned to four treatments received diets supplemented with 0 (control), 5, 10 and 20 g/kg turmeric for 3 weeks. Thereafter, the fish were exposed to lethal concentration (3.5 mg/L) of ambient copper for 24 hr and mortality was 65.3%, 41.8%, 22.7% and 20.6%, respectively. In the second experiment, the fish were fed with the aforementioned diets and simultaneously exposed to sub‐lethal concentration (0.25 mg/L) of ambient copper for 3 weeks. Copper exposure led to increases in plasma cortisol, glucose, malondialdehyde (MDA), alanine transaminase (ALT) and aspartate transaminase (AST), and decrease in plasma T₄, T₃, lysozyme, alternative complement haemolytic (ACH50), bactericidal activities, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and blood red blood cell count (RBC) and haemoglobin. Moreover, copper exposure led to significant upregulation of tumour necrosis factor‐alpha (TNF‐a) and interleukin 1‐beta (IL1‐b), and significant downregulation of interleukin 10 (IL10) gene expressions in the fish liver. Turmeric administration at 10 g/kg significantly mitigated/inhibited the copper‐induced negative effects, which seems to be due to the augmenting of the antioxidant defence.     

温度胁迫对大鳞副泥鳅抗氧化与非特异性免疫指标的影响

为研究大鳞副泥鳅(Paramisgurnus dabryanus)对温度胁迫的适应能力,开展了温度胁迫与恢复实验。设置对照组(22℃)、高温组(29℃)、降温组(15℃)与低温组(8℃)4个处理,在胁迫期的第1、2、4、8、12h与恢复期第4、8、12、24h取肝脏,测定其超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、溶菌酶(LZM)、碱性磷酸酶(AKP)活力和丙二醛(MDA)、血清谷丙转氨酶(ALT)、谷草转氨酶(AST)含量。结果显示,胁迫期内肝脏SOD和CAT活力均在温度骤变的影响下受到抑制,显著低于对照组水平(P0.05),MDA含量则显著升高(P0.05);恢复期内各实验组SOD和CAT活力均逐渐升高,MDA含量逐渐降低,至恢复期结束时,对照组与各实验组间无显著差异(P0.05)。温度骤变条件下,各实验组肝脏LZM与AKP活力显著降低(P0.05),恢复期内高温组LZM与AKP活力无明显变化,降温组与低温组LZM与AKP活力则逐渐升高,至恢复期结束时与对照组无显著差异(P0.05)。温度胁迫显著升高血清中AST与ALT含量(P0.05),恢复期内各实验组AST与ALT含量均呈下降趋势,至恢复期结束时,除高温组ALT含量外均降至对照组水平。研究表明,温度胁迫显著降低大鳞副泥鳅SOD、CAT、LZM与AKP活力,MDA与血清转氨酶AST、ALT含量升高,其中,高温胁迫会对大鳞副泥鳅非特异性免疫机能造成不可逆破坏,其他抑制均为可恢复的。     

蓝点马鲛鱼皮抗氧化肽FractionⅡ对D-Gal诱导氧化损伤大鼠肝脏的保护作用

研究蓝点马鲛鱼皮抗氧化肽FractionⅡ(1~4 ku)对氧化损伤Wistar大鼠肝脏的保护作用。采用D-半乳糖(D-gal)建立衰老模型,实验大鼠随机分为6组:空白对照组;D-Gal模型阴性对照组;D-Gal+维生素E(VE)阳性对照组;抗氧化肽低、中、高剂量组。通过检测血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)和单胺氧化酶(MAO)活性及肝组织匀浆液中超氧化物岐化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性,丙二醛(MDA)、一氧化氮(NO)含量和总抗氧化能力(T-AOC),并结合组织形态学来评价FractionⅡ对氧化损伤肝脏的作用效果。结果显示,与阴性对照相比,各剂量组的FractionⅡ能够显著降低大鼠血清中的AST和ALT活性,提高肝脏组织的SOD、GSH-Px、CAT活性和T-AOC能力,降低MDA和NO含量及MAO水平,并成一定的量效依赖关系。其中效果较好的高剂量(200 mg/kg)多肽处理组SOD、GSH-Px活性分别为236.27、182.23 U/mg蛋白,达到了正常对照及阳性对照组水平;AST、ALT分别降低至302.47和220.43 U/L,MDA含量降低至138.83 nmol/mg蛋白,也达到正常对照组水平。H.E.染色结果也证实,FractionⅡ在保护肝细胞完整性、维持结构清晰、抑制坏死等方面都有一定的效果。研究表明,蓝点马鲛鱼皮抗氧化肽FractionⅡ对D-Gal诱导的氧化损伤大鼠肝脏具有较好的保护作用。     

Antioxidant defence to ammonia stress of characins (Hyphessobrycon eques Steindachner) fed diets supplemented with carotenoids

This study aimed to find out whether dietary carotenoid (CD) supplement could influence the resistance of characins (Hyphessobrycon eques Steindachner) to ammonia stress. Two types of CD and its combination [astaxanthin (AX), β‐carotene (BC), 1 : 1 combination of AX and BC (MX)] at three concentrations (10, 20 and 40 mg kg⁻¹) were used resulting in nine pigmented diets. No differences in growth and survival of the fish among treatments were found after 8‐week rearing. Experimental and control fish were then exposed to 15 mg total ammonia nitrogen L⁻¹ (stress group) and 0.15 mg total ammonia nitrogen L⁻¹ (normal group) for 72 h, and their blood was withdrawn. No mortality resulted under such TAN concentrations. Serum total antioxidant status (TAS), serum antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidases (GPx)] and serum transaminases [alanine aminotransferase (ALT), aspartate aminotransferase (AST)] were chosen as indices of fish antioxidant capacity or stress resistance. SOD, GPx and AST were affected by the interactions of dietary CD and ammonia stress. The activities of TAS, SOD, GPx and AST increased under the stress. Dietary CD reduced serum SOD, GPx, ALT and AST activities. In conclusion, dietary CD increased the resistance of characins to ammonia stress.