盐度胁迫下维生素E对南美白对虾体内抗氧化物质含量的影响

盐度是影响虾类生存生长的重要生态因子，维生素E是机体重要的抗氧化物质。本文通过毛细管电泳法研究了不同盐度条件下添加维生素E对南美白对虾体内维生素E及NAD含量的影响，结果表明：南美白对虾饵料中维生素E的添加量为100mg/kg时，能使虾肝胰腺内的Vc和NAD的含量显著增大，发挥正常的抗氧化作用，增强南美白对虾对盐度突变的耐受力。     

低盐度水体中饲用磷酸二氢钙对南美白对虾生长的影响

在低盐度水体中 ,以添加不同含量磷酸二氢钙的试验饲料对南美白对虾幼虾 (1 37± 0 0 6 )cm进行饲养试验。结果表明 :饲料中添加磷酸二氢钙对南美白对虾的存活率、饲料系数、特定生长率均有显著影响 (P <0 0 5 )。当磷酸二氢钙添加量为 1%时 ,南美白对虾的特定生长率为最佳 ;当磷酸二氢钙添加量为3%时 ,南美白对虾的存活率为最高 ,饲料系数为最小。饲料中磷酸二氢钙对虾体组织钙磷含量 (除了肌肉中磷含量外 )有显著的影响 (P <0 0 5 )。特定生长率与肌肉Ca/P比呈显著负相关关系 (P <0 0 5 )。     

南美白对虾饲喂技术

南美白对虾以其适盐范围广，而使海虾淡养成为可能。但是低盐度或者淡水环境在一定程度上会影响南美白对虾的营养需求和生长速度，因此，掌握南美白对虾的营养需求和饲料选用及其投喂技术是开展低盐度或淡水养殖南美白对虾工作的中心线，贯穿养虾过程始终。     

淡水小棚养殖南美白对虾试验

<正>南美白对虾养殖过程中池水的温度、盐度、pH值、溶解氧以及营养盐的含量等各项指标对养殖产量的提高有极大影响。铵盐与亚硝酸盐对南美白对虾均有致毒作用。因此,了解并提高养殖过程中虾池水质是非常必要的。该文为2016年在营口天时水产公司进行的淡水小棚养殖南美白对虾试验结果,并对南美白对虾淡水养殖过程中对虾池的水质进     

黄河三角洲地区南美白对虾养殖气象条件及智慧服务研究

正滨州是黄河三角洲地区南美白对虾的主要养殖区,有着得天独厚的地理优势和自然环境。本文根据南美白对虾生长条件,结合黄河三角洲地区自然环境,对池塘内温度、PH、溶解氧、盐度进行连续的观测,分析确定了南美白对虾养殖的环境条件和养殖的关键期,提出了气象灾害对南美白对虾的影响和防御措施,建立了南美白对虾养殖智慧服务平台,使用户及时、便捷的了解未来的天气情况,指导养殖生产。     

盐度对南美白对虾生长性能的影响

在八种不同盐度条件下进行南美白对虾的养殖试验,比较其生长性能,结果表明:盐度显著地影响南美白对虾的生长(F>F0.05=3.50),其中南美白对虾在盐度为18的养殖水体中生长速度最快、存活率高、投饵系数较低;方差分析表明南美白对虾的最适生长盐度范围为14～22(｜Xi-Xj｜>LSD0.05)。     

枳实对南美白对虾健康的影响

通过在饲料中添加0．2％、0．5％、0．8％枳实来养殖南美白对虾，并对其体重增重率、体长增长率、超氧化物歧化酶(SOD)、氧化代谢产物丙二醛(MDA)、溶菌酶(LSZ)以及血淋巴细胞的吞噬能力进行测定，通过机体抗氧化系统和免疫系统，评价中草药枳实对南美白对虾健康情况的影响。结果表明：饲料中添加低剂量枳实可以显著改善SOD、吞噬活性和降低肌肉的MDA等指标，并对南美白对虾的免疫有一定的促进作用，但对生长的促进作用不大。     

地下卤水养殖对虾Ca2+适宜浓度的试验

本试验研究了经调配的地下卤水在不同盐度下,不同Ca2+浓度对南美白对虾生长的影响.通过对比盐度在10‰和20‰,在水温28℃,K+浓度在180 mg/L时的同等条件下,不同的Ca2+浓度对南美白对虾养殖的影响试验.结果表明,不同盐度相同Ca2+浓度,南美白对虾的成活率及产量差距不大;Ca2+浓度在250～330 mg/L时,南美白对虾成活率最高达95％以上,产量达15.8 kg/m2以上,达到工厂化生产要求.从养殖成活率、产量、节约成本等综合因素考虑,Ca2+浓度为250 mg/L时为本次试验的最佳添加浓度.     

南美白对虾健康养殖的小技巧怎样观察料台

南美白对虾学名凡纳滨对虾，主要分布于美洲西部太平洋沿岸的热带水域，以厄瓜多尔沿岸分布较集中，与斑节对虾、中国对虾同为世界养殖产量最高的三大优良虾种。南美白对虾个体大，抗病能力和适应能力强，生长速度快，能在低盐度水和淡水中养殖，对饲料的蛋白质含量要求较低，肉味鲜美，能鲜活运输，所以南美白对虾养殖规模越来越大。南美白对虾日增重的高低，     

pH值突变对南美白对虾仔虾淡化培育成活率的影响

南美白对虾具有生活力强．生长快，离水存活时间长．能适应低盐度生长，肉质鲜美，对饲料蛋白质需求量低．易于集约化养殖等特点。我国自1986年引种后，现已成为我国主要的养殖虾种之一。李广丽等对南美白对虾仔虾对盐度突变的适应性进行了研究．为南美白对虾的异地淡化和放养盐度调节提供了依据。有关pH突变对仔虾淡化培育成活率的影响尚未见报道。本文总结了这方面的试验结果。     

Long-term effects and interactions of dietary vitamins C and E on growth and reproduction of yellow perch, Perca flavescens

This study was conducted to examine the effects of dietary vitamin C and/or E and their interaction on growth and reproductive performance in yellow perch. Yellow perch juveniles were divided into four treatments with triplicate groups and fed with one of four semi-purified diets for 32 weeks. The experimental diets were formulated to contain no or high vitamin E levels (160 mg/kg) without or with vitamin C supplementation (250 mg/kg) designated as diets −C−E, −C+E, +C−E, or +C+E, respectively. The growth rates and survival of yellow perch fed with +C−E and +C+E diets were significantly higher than the fish fed with −C−E diet. Total- and dehydro-ascorbate concentrations in liver and testis increased in response to its dietary supplementation. The -tocopherol concentration in sperm was significantly affected by dietary supplementation of vitamin C. Gonadosomatic index of males was lower in the fish fed with −C−E diet compared to that of fish fed with other diets. Hatching rates of embryos obtained from testing sperm viability was significantly improved in fish fed with the diets sufficient in vitamin C (82±7%) compared to the fish fed with the −C−E diet (59±7). This study indicates that supplementation of dietary vitamin C and E increase growth rate, and semen quality can be improved by dietary vitamin C supplementation within one maturation cycle, and vitamin C may spare sperm vitamin E depending on vitamin E stores in tissues.     

饲料中添加不同脂肪源、VC和VE对大菱鲆生长和非特异性免疫力的影响

研究了不同脂肪源、VC和VE以及上述3种复合营养性添加剂对大菱鲆非特异性免疫力、生长和存活率的影响。结果表明,以鳀鱼鱼油为脂肪源,添加高剂量的VE能提高大菱鲆血清补体活性,并且提高大菱鲆的溶菌酶活性,但不影响大菱鲆血液的中性粒细胞吞噬率及白细胞总数;饲料中VC含量增加到250mg/kg,大菱鲆血液中的白细胞总数明显增加,而进一步提高饲料中的VC含量时,其白细胞总数没有显著变化;血清溶菌酶活性在VC含量为250mg/kg时最高。饲料中VC含量对白细胞的吞噬活性没有影响。在75d的养殖时间内,摄食复合营养性免疫增强剂的大菱鲆,其体重增重率(平均为95·3%)和成活率(99·4%)均明显高于未摄食营养型免疫增强剂的对照组体重增重率(68·0%)和成活率(93·7%)。     

饵料中不同维生素E添加量对黄颡鱼幼鱼生长和体色的影响

试验探讨了饵料中添加不同水平的维生素E对黄颡鱼生长及体色的影响,在基础饵料中分别添加0(对照组)、0.2、0.4、0.6、0.8和1.0 g/kg维生素E(含量50%)配制成1～6#饵料,在1～6#饵料中维生素E含量分别为68、175、268、364、482和562 mg/kg。在水温26～28℃下,用上述饵料分别投喂体重(21.18±13.31)g的黄颡鱼60 d,从相对增重率、饵料系数和成活率等方面来看,黄颡鱼饵料中维生素E适宜含量为268 mg/kg。     

Supplementation of ascorbic acid 2-monophosphate during the early postlarval stages of the shrimp Penaeus vannamei

A culture trial was performed using five levels of ascorbic acid 2-monophosphate (AmP at 0, 10, 100, 1000 and 2000 mg kg⁻¹ diet, expressed as active ascorbic acid, AA) in a semipurified diet for early postlarval Penaeus vannamei. The experiment started 10 days after metamorphosis of the mysid larvae into postlarvae (=PL10). Each treatment was run in four replicates. P. vannamei postlarvae showed significantly better growth according to dietary AA level after 25 days of feeding, i.e. at PL36 stage. Whereas the dry weight of PL36 in the control treatment (0 mg AA kg⁻¹ diet) was only 2 mg, supplementation of 1000 mg AA kg⁻¹ increased the shrimp dry weight up to 18 mg. However, the growth in the other treatments was not significantly different from the control. Fitting a broken-line regression to the biomass yield demonstrated an optimal dietary level of 130 mg AA kg⁻¹ diet. There were no differences observed among the treatments in stress resistance of postlarval P. vannamei to a salinity shock.     

饲料Vc对大菱鲆非特异性免疫力的影响

X用维生素C（Vc）含量为0～2500mg／kg的配合饲料连续投喂大菱鲆70d后，测定大菱鲆血液白细胞的总数、吞噬活性、血清溶菌酶活性和总补体活性。结果表明，饲料中Vc含量增加到250mg／kg，白细胞总数明显增加，进一步提高Vc含量，白细胞总数没有显著变化；血清溶菌酶活性在Vc含量为250mg／kg时最高，其他各组无显著性差异；添加Vc的各试验组的总补体活性明显地高于对照组，但是添加Vc的各组之间的总补体活性没有显著性差别；Vc含量对白细胞的吞噬活性没有影响。     

Dietary vitamin E requirement, fish performance and carcass composition of rohu (Labeo rohita) fry

A 90-day feeding experiment was conducted using flow through system to evaluate the requirement of vitamin E for rohu fry in relation to growth performance and to assess the relationship between the dietary vitamin E levels and carcass composition. Five semi-purified diets supplemented with 0, 50, 100, 150, 200 mg vitamin E/kg dry diet as --tocopheryl acetate were fed to rohu fry (av. wt.±S.E.=0.58±0.01 g) in triplicate groups. At the end of the experiment, growth and dietary performance were evaluated and vitamin E deposition in the tissue, erythrocyte fragility, thiobarbituric acid reactive substances (TBARs) were analyzed. The average net weight gains were 6.82±0.09, 7.38±0.03, 8.20±0.03, 8.07±0.09 and 8.12±0.08 (g/90 days), respectively, for fish fed diets 0, 50, 100, 150, 200 mg vitamin E/kg. The fish fed diets containing less than 100 mg supplemental vitamin E/kg had significantly (P<0.05) reduced weight gain, feed efficiency and other nutritional indices compared to those fed diets supplemented with vitamin E at 100–200 mg/kg. With the increasing level of vitamin E, both TBARs and erythrocyte fragility values were reduced. Regression analysis of weight gain data using broken-line model indicated a minimum vitamin E requirement of 131.91 mg/kg dry diet. The erythrocyte fragility and TBARs were maximum in fish fed the vitamin E-deficient diet. From the present experiment, it may be concluded that the vitamin E requirement of Labeo rohita fry for optimum growth and other dietary performances is 131.91 mg/kg of dry diet.     

不同维生素E水平饲料对云纹石斑鱼幼鱼低盐胁迫前后抗氧化和渗透压调节功能的比较

维生素E(VE)在鱼类繁殖、生长代谢、抗氧化能力和免疫机能等方面有至关重要的作用。为探究饲料VE添加量对云纹石斑鱼低盐度胁迫下抗氧化和渗透压调节功能的作用,本实验设计0、20、40、80和160 mg/kg等5个VE水平饵料添加量,依次为A、B、C、D、E组,饲喂云纹石斑鱼幼鱼56 d。然后进行6 h低盐度(12)胁迫实验,测试皮质醇(COR)、葡萄糖(GLU)、乳酸(LD)等血清生化指标,超氧化物岐化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、总抗氧化能力(T-AOC)和丙二醛(MDA)等抗氧化指标,以及鳃Na⁺/K⁺-ATP酶(NKA)、Ca²⁺-ATP酶活力等。结果显示,血清COR含量最高为盐度胁迫后A(32.74±1.53) ng/mL,最低为胁迫前E(19.06±3.88) ng/mL;GLU含量最高为盐度胁迫后A(16.46±0.99) mmol/L,最低为养殖前O(7.90±0.34) mmol/L;LD含量最高为低盐度胁迫前C(1.94±0.15) mmol/L,最低为胁迫后E组(1.30±0.06) mmol/L。说明VE的添加可以增强云纹石斑鱼抗应激的能力,且在47.524~134.566 mg/kg(B~D)的添加范围,效果较好。血清SOD、CAT、GSH-Px活力、T-AOC和MDA含量与投喂饲料中VE水平密切相关,SOD最高为胁迫前C(105.29±9.07) U/mL,最低为胁迫后A(11.23±2.30) U/mL;CAT最高为养殖前O(4.09±0.17) U/mL,最低为胁迫后A(0.35±0.10) U/mL;GSH-Px最高为胁迫前E(972.58±55.35) U,最低为胁迫后A(47.90±10.64) U;MDA最低为胁迫前D(33.48±2.34) nmol/mL,最高为胁迫后A(101.79±7.79) nmol/mL。饲料中添加91.378~178.924 mg/kg(C~E)水平VE对其抗氧化能力有增强作用。VE可增强NKA活力,当VE添加量为91.378 mg/kg(C)时,低盐度胁迫对NKA影响较小。而添加91.378~178.924 mg/kg(C~E)水平VE可增强云纹石斑鱼Ca²⁺-ATP酶活力。研究表明,饲料中添加91.378~134.566 mg/kg范围的维生素E,可以增强云纹石斑鱼的机体活力、抗应激及环境胁迫能力。     

Effects of dietary vitamin E and astaxanthin on growth,skin colour and antioxidative capacity of large yellow croaker Larimichthys crocea

A 10‐week feeding trial was conducted to evaluate the effect of dietary vitamin E and astaxanthin on growth performance, skin colour and antioxidative capacity of large yellow croaker Larimichthys crocea. Six practical diets were formulated in a 2 × 3 factorial design to supplement with two levels of astaxanthin (25 and 50 mg/kg) and three levels of vitamin E (0, 120 and 800 mg/kg). The results showed that both the highest final body weight and specific growth rate were found in fish fed diets with 120 mg/kg vitamin E supplementation. No significant differences were found in survival rate, feed conversion ratio and protein efficiency ratio among all the treatments (p > .05). Skin lightness (L*) was not significantly affected by dietary treatments (p > .05). Ventral skin redness (a*) of fish fed diet with 25 mg/kg astaxanthin and 0 mg/kg vitamin E supplementation was significantly lower than that of fish fed with other diets. Yellowness (b*) and carotenoid contents both in the dorsal and in the ventral skin were found to be significantly increased with increasing dietary astaxanthin or vitamin E (p < .05), but no significant interactions were found (p > .05). The vitamin E content in liver reflected the dietary vitamin E content. Level of vitamin E content in fish fed diets with 800 mg/kg vitamin E supplementation was significantly higher than that in fish fed with the other diets (p < .05). Liver superoxide dismutase activity and thiobarbituric acid reactive substance levels were found to be decreased with increasing dietary astaxanthin and vitamin E levels, respectively. Levels of reduced glutathione in the liver were found to be increased with increasing dietary vitamin E contents. The total antioxidative capacity in the liver was found to be decreased with increasing dietary vitamin E or astaxanthin contents. In conclusion, adequate dietary vitamin E can improve the growth of large yellow croaker, and the supplementation of astaxanthin and vitamin E benefited the skin coloration and antioxidative capacity of large yellow croaker.     

Effects of dietary vitamin E supplementation on growth performance,fatty acid composition,lipid peroxidation and peroxisome proliferator-activated receptors (PPAR) expressions in juvenile blunt snout bream <Emphasis Type="Italic">Megalobrama amblycephala</Emphasis>

A 9-week feeding experiment was conducted to evaluate the effects of dietary vitamin E (VE) supplementation on growth performance, liver fatty acid composition, lipid peroxidation and peroxisome proliferator-activated receptors (PPAR) genes expressions in blunt snout bream juveniles. Fish (average initial weight: 0.59 g) were fed diet supplemented with 0, 50, 100, 300 and 500 mg α-tocopherol acetate/kg in triplicates, which were found to, respectively, contain 11.2, 56.3, 114.6, 306.5 and 588.4 mg α-tocopherol/kg diet. Results showed that final weight, body weight gain and specific growth rate significantly increased with increasing dietary VE supplemented level from 11.2 to 56.3 mg/kg. When the broken-line model was employed to estimate the adequate requirement of vitamin E based on body weight gain, the optimal level was 55.5 mg/kg in diet. Hepatosomatic index value significantly decreased with incremental dietary VE levels. However, liver VE concentration showed a direct relationship with the dietary VE level. The percentages of 20:5n-3, 22:6n-3 and total n-3 long chain polyunsaturated fatty acids in liver increased with increasing dietary VE supplementation. Meanwhile, the expressions of PPAR-α, PPAR-β and PPAR-γ in liver were down-regulated by supplementation of dietary VE level from 56.3 to 588.4 mg/kg. In conclusion, supplementation of more than 55.5 mg/kg vitamin E may improve growth and increase n-3 LC-PUFA content in blunt snout bream, which is beneficial to human consumer.     

The effects of vitamin E on non-specific immune response of the juvenile soft-shelled turtle <Emphasis Type="Italic">Pelodiscus sinensis</Emphasis>

ABSTRACT:   This study was conducted to determine the effect of dietary vitamin E supplements on non-specific immune responses in juvenile soft-shelled turtles. Turtles were fed diets supplemented with vitamin E at 0 (control), 50, 250, 500, 1000 and 5000 mg/kg, respectively, for 4 weeks. Results showed that blood cell phagocytosis and serum bactericidal activity were significantly improved in turtles from two diets (250 and 500 mg/kg vitamin E supplementation), while had no significant improvement in turtles from the three remaining diets (50, 1000 and 5000 mg/kg vitamin E supplementation) when compared to turtles from the control group. Serum bacteriolytic activity in turtles from diets with 50, 250, 500 and 1000 mg/kg vitamin E supplementation were higher than activity levels quantified for the control group, but no significant difference was observed between the 5000 mg/kg vitamin E supplementation diet and the control diet. The results suggest that vitamin E has an upper and lower threshold for improving non-specific immune function in soft-shelled turtles, and the optimal supplementation may be between 250 and 500 mg/kg.