多聚磷酸钠胁迫下硒对中华米虾抗氧化酶活性的影响

研究了在多聚磷酸钠胁迫下,18~20℃,饲料中添加硒对中华米虾抗氧化酶系统的影响。试验结果表明,多聚磷酸钠对中华米虾24、48、72、96 h半致死质量浓度分别为1.24、1.20、1.17、1.16 g/L。在多聚磷酸钠胁迫下,饲料添加硒的试验组米虾抗氧化酶的活性较对照组高。适量的硒有利于提高中华米虾抗氧化酶的活性,可提高对环境胁迫的耐受力。     

氯氰菊酯胁迫下锰对中华米虾SOD活性的影响

水温25 ℃,氯氰菊酯对中华米虾24、48、72、96 h的半致死质量浓度分别为93、83、81、77 ng/L.饲料中加入适量的锰与不加锰分别投喂中华米虾,在0～77 ng/L氯氰菊酯胁迫下测定米虾肌肉中超氧化物歧化酶(SOD)的活性.试验结果表明,无锰组和有锰组的SOD活性随着氯氰菊酯的胁迫质量浓度升高,先升高后下降.有锰组在氯氰菊酯质量浓度为8 ng/L时,SOD活性达到最大;无锰组在氯氰菊酯质量浓度为42 ng/L时,SOD活性达到最大.有锰组的中华米虾SOD的活性基本高于无锰组, SOD活性表明饲料中加适量的锰比不加锰更有利于提高中华米虾机体的抗氧化性和对氯氰菊酯毒害的抵抗力.     

虾青素对微囊藻毒素MC-LR胁迫下克氏原螯虾的生长、繁殖及免疫力的影响

本文目的旨在研究虾青素对微囊藻毒素MC-LR胁迫下(25μg/L)克氏原螯虾的免疫力及生长繁殖的影响。实验设计四个梯度的饲料中虾青素添加比例分别为(0、5、10、20 mg/g)养殖周期持续8星期。结果表明虾青素显著提高了克氏原螯虾肝脏中超氧化物歧化酶(SOD)和碱性磷酸(AKP)的活力(P0.05)。5g/kg虾青素的添加量即可对SOD酶活具有明显提升(P0.05);10 g/kg的虾青素添加量对AKP的提升最为明显(P0.05);研究还发现虾青素可显著提高微囊藻毒素MC-LR胁迫下克氏原螯虾的存活率和特定生长率(SGR)(P0.05),提高克氏原螯虾雌虾的抱卵量。研究表明虾青素作为一种抗氧化剂适宜于在克氏原螯虾饲料中添加,并且具有提高虾体免疫活力,缓解微囊藻毒素MC-LR对虾体氧化胁迫的作用。     

有机硒对汞致日本沼虾毒性的拮抗作用

研究了饲料中添加0.45 μg/g的富硒酵母对日本沼虾生长及对Hg2+毒性的拮抗作用,探明SOD作为Hg胁迫指标的可行性.选择体长2.6～3.0 cm、体质量0.30～0.40 g的日本沼虾,暂养于 60 cm×30 cm×45 cm的水族缸中,投喂含豆油、面粉、豆粉、玉米面、维生素预混物、无机盐预混物的配合饲料.结果表明,有机硒组的体长和体质量增长率均大于无硒对照组;有机硒组和无硒对照组中日本沼虾的SOD活力均随HgCl2质量浓度呈现峰值变化;说明饲料中添加适量有机硒可促进机体生长,提高机体SOD的活力,在一定程度上拮抗HgCl2所致的毒性.     

多氯联苯对大弹涂鱼的急性毒性以及氧化应激

测定Aroclor 1248对大弹涂鱼96 h的半数致死浓度(LC50);进而以浓度为10和100μg/L的Aroclor1248溶液对大弹涂鱼经口染毒28 d,测定其总SOD、CAT、GPx、活性以及脂质过氧化产物丙二醛(MDA)含量。结果表明Aroclor1248对大弹涂鱼的96 h LC50为295.15μg/L。暴露于10μg/L Aroclor 1248 28 d的大弹涂鱼SOD活性明显大于空白和100μg/L剂量组(p0.05),添加Aroclor 1248的实验组中CAT活性均高于对照组,100μg/L Aroclor 1248强度下GPx活性明显高于其他三组(p0.05),10μg/L Aroclor 1248强度下GPx活性略高于对照组。100μg/L Aroclor 1248强度中MDA明显高于其他三组(p0.05),表明Aroclor1248对大弹涂鱼抗氧化和脂质过氧化系统有明显干扰作用。     

硒胁迫对小球藻的生物学影响

以0、5、10、20、30 mg/L硒(亚硒酸钠)分别对小球藻进行胁迫培养,研究不同浓度硒胁迫对小球藻生物量、细胞内硒含量、谷胱甘肽过氧化物酶(GSH-Px)活性和超氧化物歧化酶(SOD)活性的影响。结果表明:高浓度(30 mg/L)硒胁迫将促使小球藻提早进入衰亡期;藻细胞内硒含量、GSH-Px酶活性随硒胁迫浓度的增加而增大,硒添加浓度为5、10、20和30 mg/L时,GSH-Px酶的活性分别是对照组的5.59、6.98、11.32和11.52倍;而只有当硒胁迫浓度达到20 mg/L以上时,才会导致SOD酶活性显著增大。此外,采用尺寸排阻色谱与电感耦合等离子体质谱联用(SE-HPLC-ICP-MS)技术对藻细胞内硒结合形态进行分析,发现了硒有3种主要的结合形态。     

溴氰菊酯对克氏原螯虾的氧化胁迫效应

为了解溴氰菊酯对克氏原螯虾的毒性及致毒机理,采用24h换水式生物试验研究了溴氰菊酯对克氏原螯虾的96h急性毒性,分光光度法检测了6、12、24和48h后0.01、0.02和0.04μg/L溴氰菊酯对肝胰腺超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活力和丙二醛(MDA)的含量等氧化胁迫相关指标的影响。结果表明,24、48和96h的半致死浓度分别为0.1560、0.0993和0.0562μg/L,安全浓度为5.62ng/L;在整个暴露过程中,溴氰菊酯各个处理组都引起了氧化胁迫相关指标的变化。SOD和CAT活力的变化趋势相同,都呈抑制-诱导-抑制的变化规律,MDA含量则一直高于对照组。暴露6h后,0.01μg/L浓度组MDA含量极显著高于对照组(P<0.01),0.04μg/L浓度组MDA含量约为对照组的1.98倍(P<0.05);暴露12h后,MDA仍保持较高水平,0.02μg/L浓度组MDA含量约为对照组的1.76倍(P<0.05);暴露24h后,各浓度组CAT活力分别比对照组上升了70.98%、73.05%和66.67%(P<0.01);暴露48h后,0.01、0.02μg/L浓度组的SOD活力分别下降了...     

农药锐劲特对锯齿米虾的毒性试验

采用常温静水实验法进行了5%锐劲特悬乳剂对锯齿米虾的急性毒性试验。结果表明:锐劲特对锯齿米虾24h、48h、96h的半致死浓度(LC50)分别为:32.36μg/L、17.38μg/L、10.23μg/L。     

海水中Zn2+和Mn2+对日本对虾仔虾体内碱性磷酸酶活性的影响

分别在经过螯合剂Cephlex100处理的海水中添加Zn^2 和Mn^2 培养日本对虾仔虾，观察金属离子对其变态发育及体内碱性磷酸酶的影响。结果显示，当海水中Zn^2 为20－40μg/L时可以明显激活仔虾体内碱性磷酸酶的活性，但大于此浓度时则使该酶的活性降低；当海水添加Mn^2 时均能提高仔虾体内碱性磷酸酶的活性，浓度在40μg/L时碱性磷酸酶的活性最高，碱性磷酸酶活性的高低可作为判别环境因素是否适合对虾幼体生存的指标。     

氯氰菊酯对草鱼鳃和肝组织超氧化物歧化酶(SOD)活性的影响

在实验室条件下,研究了氯氰菊酯对草鱼鱼种的急性毒性及其对鳃和肝组织超氧化物歧化酶(SOD)活性的影响。结果表明,氯氰菊酯对草鱼鱼种24,48,72,96h半致死浓度分别为32 82μg L、9 92μg L、8 12μg L、6 51μg L;经1μg L、3μg L、5μg L浓度处理,测得鳃SOD活性6h时升高,后转为抑制,对肝脏SOD酶呈现促进作用,酶活性的变化呈一定浓度相关性。     

Effect of dietary vitamin C and ammonia concentration on the cellular defense response of Macrobrachium nipponense

This study examined the effects of dietary vitamin C and ammonia concentration on the cellular defense response of Macrobrachium nipponese . The response of the cellular defense was determined by monitoring changes in reactive oxygen intermediates in hemocytes, superoxide dismutase activity, catalase activity, glutathione peroxidase activity, glutathione reductase and glutathione transferase activity in muscle. The results showed that prawns fed the basal diet had a significant increase in reactive oxygen intermediates in response to exposure to ammonia-N. When dietary vitamin C was added to the feed, there was a significant decrease in reactive oxygen intermediates in response to exposure to ammonia-N. Total superoxide dismutase and glutathione peroxidase activity of prawns fed the basal diet decreased as ammonia-N increased. This decrease in activity was significantly less pronounced in prawns that were fed the dietary vitamin C supplement. In prawns that were fed the dietary vitamin C supplement there was no significant variation in catalase reductase or gluxathione reductase activity in response to variations in ammonia-N concentration. The glutathione transference activity increased at a low concentration of ammonia-N in prawns that were fed the dietary vitamin C supplement, but there was no significant variation in the prawns fed the basal diet. Overall the results indicate that dietary vitamin C supplements enhance the capacity of M. nipponese to respond to elevations in ammonia-N. This response involved several biochemical reactions known to be involved in cellular defense.     

左旋咪唑对罗氏沼虾免疫功能及抗病力的影响

以0(对照)、50、100和150 mg/kg饲料的剂量将左旋咪唑(LMS)添加于基础饲料中制成颗粒饲料投喂罗氏沼虾(Macrobrachium rosenbergii)14 d,采样测定了罗氏沼虾血细胞吞噬活性、血清酚氧化酶(PO)、溶菌酶(LSZ)及超氧化物岐化酶(SOD)活性,并以6×105cells/mL浓度的致病性嗜水气单胞菌(Aerom onas hydrophila)对罗氏沼虾进行肌肉注射(20μL/尾),记录接种7 d后罗氏沼虾的累积死亡率。结果表明,3个LMS处理组的罗氏沼虾血细胞吞噬百分比和吞噬指数、血清PO、LSZ及SOD活性均显著地高于对照组(P<0.05);LMS处理组的罗氏沼虾对嗜水气单胞菌的抵抗力明显增强。因此,饲喂适量的LMS能促进罗氏沼虾的免疫力和抗病力;在本试验条件下,100 mg/kg饲料的剂量为最适添加剂量。     

Effects of dietary mannan oligosaccharide on growth,survival, physiological,immunological and gut morphological conditions of black tiger prawn (Penaeus monodon Fabricius 1798)

The aim of this experiment was to determine the effects of dietary inclusion with mannan oligosaccharide (Bio‐Mos, Alltech, Nicholasville, KY, USA) on growth, survival, physiological and immunological conditions and gut morphology of the black tiger prawn (Penaeus monodon). Five diets supplemented with MOS at 0 g kg^?1 (control diet), 1, 2, 4 and 8 g kg^?1 were fed to the prawn juveniles (0.4 ± 0.06 g, total weight) for the duration of 63 days. Growth was the highest (P < 0.05) when the prawns were fed the 1 g kg^?1 MOS included diet. Wet tail muscle index (Tw/B), dry tail muscle index (Td/B) and tail muscle protein (Tmp) were higher (P < 0.05) in the prawns fed MOS included diets MOS compared with the prawns fed the control diet. Total haemocyte counts (THCs) of the prawns fed MOS included diets were higher (P < 0.05) than THCs of the prawns fed the control diet. Epithelium layer and epidermal cell density of the gut of the prawns fed 1 g kg^?1 and 2 g kg^?1 MOS diets were better than the prawns fed the control and other MOS diets. The results imply a positive effect of dietary supplementation of 1–2 g kg^?1 MOS in the culture of black tiger prawns.     

Assessment of cholesterol requirements in the prawn, Penaeus japonicus

Two feeding experiments were conducted to assess the quantitative cholesterol requirement of the juvenile prawn, Penaeus japonicus . The prawns were fed casein-based (experiment 1) and casein- or crab protein-based (experiment 2) diets with or without supplemental cholesterol. The daily increases in quantities of body cholesterol (mg kg⁻¹ prawn day⁻¹) at maximum growth and dietary cholesterol intake over a 40-day feeding period were determined. Prawns fed 5 g kg⁻¹ supplemental cholesterol, regardless of protein sources, gave the highest weight gain. Body retention efficiencies of dietary cholesterol (cholesterol retained × 100/cholesterol intake) vary among prawns fed 5 g kg⁻¹ supplemental cholesterol (diets 3, 5 and 7) but dietary cholesterol requirements expressed as mg kg⁻¹ body weight (BW) day⁻¹ were not significantly different (180 to 200 mg kg⁻¹ BW day⁻¹). Based on dietary cholesterol requirement, the optimum dietary cholesterol levels for the juvenile prawns were estimated in relation to feeding levels. When feeding levels were 3%, 5% and 7% of body weight, optimum dietary cholesterol levels were 5.0 to 6.0, 3.6 to 4.0, and 2.6 to 2.9 g kg⁻¹ of dry diet, respectively. The present study showed the advantages of determining daily cholesterol requirement (mg kg⁻¹ BW day⁻¹) at maximum growth through a factorial method in determining optimum dietary cholesterol levels in P. japonicus .     

Effects of selenium dietary enhancement on hatchery-reared coho salmon, Oncorhynchus kisutch (Walbaum), when compared with wild coho: hepatic enzymes and seawater adaptation evaluated

Hatchery-reared coho salmon, Oncorhynchus kisutch (Walbaum), were fed elevated levels of selenium (as Na₂SeO₃) to raise eviscerated body burdens to the level measured in wild counterparts. The goal was to find a dietary concentration that would achieve the desired effect without causing damage to growth and normal development. To measure some indices of health, the detoxifying enzymes chosen were hepatic glutathione peroxidase (GSH-Px) and hepatic superoxide dismutase (SOD). Eviscerated body selenium (Se) concentration, GSH-Px and SOD levels were measured during and at the end of the 9 month freshwater feeding trial. Selenium retention and enzyme activity were also measured during 6 months’residence in sea water (SW). Selenium supplements were added to a commercial ration to give final concentrations of 1.1, 8.6, 11.1, 13.6 μg g^-1 Se in the four respective diets. The results indicated that a dietary concentration of 8.6 μg g^-1 selenium was capable of inducing eviscerated body burdens similar to those found in wild fish. The elevated selenium levels persisted throughout the freshwater (FW) rearing phase, but declined when the fish were fed an unsupplemented ration upon SW entry. Superoxide dismutase levels did not increase above control levels. Glutathione peroxidase levels increased in fish fed the supplemented diets. GSH-Px activity declined in the higher supplemented dietary groups when all groups were reduced to the control group level of 1.1 μg g^-1. Cumulative mortality in SW was 20% in fish fed either the 1.1 or the 8.6 μg g^-1 Se diets. The 8.6 μg g^-1 Se supplemented diets did produce healthy coho, comparable to their wild counterparts.     

饲料中黄曲霉毒素B1对凡纳滨对虾生长、肝胰腺和血淋巴生化指标及肝胰腺显微结构的影响

实验设置黄曲霉毒素B1(AFB1)为0、400、800、1200,1600、2000μg/kg6组饲料,饲养初始体质量为(0.3±0.02)g的凡纳滨对虾,经过8周的生长实验观察饲料中AFB1对凡纳滨对虾生长、体营养成分组成、肝胰腺显微结构以及血淋巴和肝胰腺生化指标的影响。实验结果表明:随着饲料中AFB1的增加,各组全虾粗蛋白量无显著性差异,1600μg/kg组和2000μg/kg组的全虾粗脂肪量高于其他组。AFB1为1200μg/kg时对虾增重率最低(304.67%),2000μg/kg时增重率显著高于其他组,但成活率最低(58.33%)。随着饲料中AFB1的升高酶活性普遍呈下降趋势。2000μg/kg组肝胰腺中总抗氧化能力(T-AOC)显著下降(P<0.05),1600μg/kg组肝胰腺中谷胱甘肽S转移酶(GST)、超微量ATP酶和超氧化物歧化酶(SOD)酶活力最低,但血淋巴中GST显著高于其他各组(P<0.05)。从凡纳滨对虾肝胰腺的组织切片可观察到,饲料中含有的AFB1越高,肝胰腺被破坏程度越高。随着饲料中AFB1含量增加,对虾肝胰腺中AFB1残留量逐渐增加,2000μg/kg组对虾肝胰腺中AFB1含量最高(95.49μg/kg),各实验组肌肉中无AFB1残留。     

Growth and metabolic responses of juvenile Macrobrachium nipponense to different dietary carbohydrate levels

It remains controversial whether carbohydrate can be efficiently used by crustaceans. Six isonitrogenous and isolipid diets were formulated containing 50–350 g kg^–1 corn starch and were fed to juvenile prawns (mean weight, 0.133 ± 0.003 g) for 56 days in five replicates. Prawns fed 50–150 g kg^–1 corn starch attained significantly greater weight gain. Digestive enzyme activities were significantly affected by dietary corn starch level. Hepatopancreatic and muscle glycogen levels peaked in prawns fed 350 g kg^–1 and 150 g kg^–1 corn starch content, respectively. Prawns fed 350 g kg^–1 corn starch had a significantly higher haemolymph glucose level than that in the other groups. Hepatopancreatic hexokinase (HK) activity increased significantly as corn starch level was increased. Hepatopancreatic pyruvate kinase (PK) activity of prawns fed the 150 g kg^–1 and 250 g kg^–1 corn starch was significantly higher than that of prawns fed 50 g kg^–1 corn starch. Including carbohydrate in the diet promoted increased lipogenic activities (glucose‐6‐phosphate dehydrogenase and malic enzyme) in the hepatopancreas. Hepatopancreatic HK and PK mRNA expression levels had similar trends with their activities. The 350 g kg^–1 corn starch level induced the highest glucose‐6‐phosphatase and pyruvate carboxylase mRNA expression levels. Overall, moderate metabolic adaptations for using dietary corn starch were detected in Macrobrachium nipponense; however, a high proportion (>150 g kg^–1 ) of corn starch in the diet may reduce growth.     

动植物蛋白对日本沼虾生长、肌肉组成、抗氧化、TOR信号通路及食欲调节相关基因表达的影响

为探讨动植物蛋白对日本沼虾生长、肌肉组成、抗氧化、TOR信号通路及食欲调节相关基因表达的影响,实验配制了3组等氮等能饲料,分别为鱼粉组(FM)、混合植物蛋白组(豆粕,菜粕,玉米蛋白粉)(PPB)和混合植物蛋白添加氨基酸组(PPB/Aa),投喂饲养日本沼虾8周。结果发现,PPB和PPB/Aa组日本沼虾增重率和摄食率显著低于FM组,而饲料系数显著高于FM组,各组之间成活率和肌肉必需氨基酸组成无显著差异;FM组肝胰腺丙二醛(MDA)含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性显著低于PPB组和PPB/Aa组,各组谷草转氨酶(AST)和谷丙转氨酶(ALT)无显著差异,PPB与PPB/Aa组血清碱性磷酸酶(AKP)、酸性磷酸酶(ACP)和ALT的活性均显著高于FM组;与FM组相比,PPB与PPB/Aa组显著降低了雷帕霉素靶蛋白(TOR)、核糖体蛋白S6激酶(S6K)及神经肽(NPY)基因的表达,但各组瘦素(leptin)基因的表达无显著差异。研究表明,鱼粉与混合植物蛋白对日本沼虾肌肉中氨基酸组成无显著影响,但混合植物蛋白源降低了虾的生长和抗氧化能力及TOR信号通路与NP...     

Dietary copper requirements of juvenile grouper, Epinephelus malabaricus

To quantify dietary copper (Cu) requirements in grouper, Epinephelus malabaricus, copper sulfate was added to the basal diet at 0, 1, 2, 4, 6, 8, 10 and 20 mg Cu/kg diet providing the actual dietary value of 0.11, 1.66, 2.41, 4.37, 6.56, 8.97, 11.03 and 20.05 mg Cu/kg diet, respectively. Each diet was fed to triplicate groups of grouper (initial body weight 13.35 ± 0.01 g) in a recirculated rearing system for 8 weeks. The Cu concentration in rearing water was monitored during the feeding period and ranged from 1.0-1.5 μg/l. Weight gain (WG) and feed efficiency (FE) were higher (P < 0.05) in fish fed diets with 4.37 and 6.56 mg Cu/kg diet than those in fish fed diets with ≥ 11.03 and ≤ 1.66 mg Cu/kg diet. Hepatic thiobarbituric acid reactive substances (TBARS) value was lowest in fish fed diets with 4.37 and 6.56 mg Cu/kg diet, intermediate in fish fed diets with 11.03 and ≤ 1.66 mg Cu/kg diet, and highest in fish fed the diet with 20.05 mg Cu/kg diet. Differences between each of the three groups were statistically significant (P < 0.05). Both hepatic copper-zinc superoxide dismutase (Cu-Zn SOD) and plasma ceruloplasmin activities in fish fell into four groups. Cu-Zn SOD value was highest in fish fed the diet with 6.56 mg Cu/kg diet, second highest in fish fed the diet with 8.97 mg Cu/kg diet, intermediate in fish fed the diet with 20.05 mg Cu/kg diet, and lowest in fish fed the diet with 0.11 mg Cu/kg diet; plasma ceruloplasmin was highest in fish fed the diet with 6.56 mg Cu/kg diet, second highest in fish fed diets with 2.41, 4.37 and 8.97 mg Cu/kg diet, intermediate in fish fed diets with ≥ 11.03 mg Cu/kg diet, and lowest in fish fed diets with ≤ 1.66 mg Cu/kg diet. All values in each of the four groups were significantly different from the values of three other groups (P < 0.05). Analysis by broken-line regression of WG, hepatic SOD activity and TBARS value and linear regression of whole-body Cu retention of the fish indicate that the adequate dietary Cu concentration in growing grouper is about 4-6 mg Cu/kg diet.