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This study was conducted to evaluate the effects of different concentrations of dietary lipids on body composition and liver function in juvenile red drum, Sciaenops ocellatus. Diets were formulated to contain 40% crude protein from solvent-extracted menhaden fish meal and 0, 7, 14 or 21% lipid from menhaden fish oil. The basal diet, without supplemental fish oil, contained lipid at 0.4% of dry weight. The diets were fed to groups of 25 juvenile red drum initially averaging 7.3 ± 0.18 g fish–1 in a recirculating culture system for 8 weeks and weight gain was recorded. After an additional 8 weeks, 16 fish from each treatment were sacrificed and the following measurements were recorded: hepatosomatic index (HSI), intraperitoneal fat (IPF) ratio, and liver -tocopherol, malondialdehyde (MDA) formation, and cytochrome P-4501A activity (measured as 7-ethoxyresorufin O-deethylase (EROD) activity). The activity of alanine and aspartate aminotransferases and concentrations of -tocopherol also were measured in plasma.Weight gain was significantly (p<0.05) affected by dietary lipid concentration, with values ranging from 361% of initial weight for fish fed the basal diet to 527% of initial weight for fish fed the diet containing 7% lipid. The HSI and IPF ratio values also were significantly affected by lipid with the lowest values recorded for fish fed the basal diet and the highest values observed in fish fed the diet containing 21% lipid. Increasing dietary lipid significantly increased oxidative stress as reflected in reduced -tocopherol in liver and plasma and increased MDA formation in the liver, although no overt pathological signs were observed. These findings suggest that lipid concentrations between 7 and 14%, when the diet contains 60 IU vitamin E kg–1, are likely to limit oxidative stress and result in normal physiological responses of red drum.  相似文献   
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The effect of aflatoxin treatment and/or feeding of a high level of α‐tocopherol on immune response and disease resistance was investigated in Indian major carp, Labeo rohita. Group A served as a healthy control, group B was treated with aflatoxin, group C was fed a high level of α‐tocopherol whereas group D was exposed both to aflatoxin and a high level of dietary α‐tocopherol for 60 days. Aflatoxin B1 (AFB1) was injected once intraperitoneally into fish on the first day of the experiment (groups B & D). High levels of DL‐α‐tocopherol (1000 mg kg–1 feed) were provided to healthy as well as AFB1‐treated immunocompromised fish for 60 days (groups C & D). At the end of the experiment blood samples were assayed for changes in nonspecific immunity and humoral protein levels. Disease resistance against two common bacterial pathogens viz., Aeromonas hydrophila and Edwardsiella tarda were evaluated in all groups. Significant (P < 0.05) suppression of specific immunity as measured through haemagglutination (HA) titre against sheep red blood cells (SRBCs) as well as bacterial (formalin‐killed E. tarda) agglutination titre; nonspecific resistance factors viz., globulin level, serum bactericidal and lysozyme activities, neutrophil activities, and disease resistance against two bacterial pathogens only in aflatoxin‐treated fish with respect to the control group, clearly indicated the immunosuppressive nature of aflatoxin. Feeding of a high level of α‐tocopherol to AFB1‐treated immunocompromised fish significantly (P < 0.05) raised specific immunity, nonspecific resistance factors and disease resistance capacity when compared with aflatoxin‐exposed fish. Disease resistance and enhancement of immune status through feeding of high levels of α‐tocopherol to healthy as well as AFB1‐treated immunocompromised fish confirmed the potential of α‐tocopherol in carp feed for prevention of disease and for combating natural/environmental immunosuppressants.  相似文献   
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Rainbow trout were fed three experimental diets with varying levels of vitamin E (α‐tocopherol) supplementation (0, 100 and 1000 mg kg?1 diet), and the effects of feeding these diets on serum spontaneous haemolytic activity and classical complement activity were investigated. Hepatic α‐tocopherol levels reflected the dietary intake of the vitamin. Fish fed the diet deficient in vitamin E showed reduced growth and increased mortality. Their hepatosomatic index and erythrocyte fragility was significantly higher than both the supplemented groups and haematocrit, and complement activity were all significantly lower. There appeared to be some enhancement of serum complement activity correlated with increased dietary supplementation with vitamin E but the benefits of supplementation at levels above those currently recommended were not established.  相似文献   
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Juvenile African catfish, Clarias gariepinus (Burchell), of mean initial weight 15 g, were fed practical diets containing fresh or rancid oil (1:1 cod liver:corn oil) supplemented with either 20 or 100 mg all-rac-α-tocopheryl acetate per kg dry diet, at 0.03 × body weight per day for 8 weeks. After this time, catfish had grown by at least four times in body weight. Significant ( P < 0.05) inter-treatment differences in final body weight were noted. Clarias fed low-tocopherol: oxidized-oil diets performed least well with regard to growth, though elevated dietary vitamin E partially abrogated this effect. Growth of fish fed fresh-oil diets did not benefit from increased dietary α-tocopherol content. Muscle, liver, plasma, heart and spleen all responded significantly ( P < 0.05) to dietary vitamin E dose. Inclusion of oxidized oil in catfish diets decreased tissue α-tocopherol concentration. Hepatic α-tocopherol concentration (μg α-tocopherol per g liver) was observed to be lowered by 90% by the rancid oil diets. When fish previously fed fresh-oil diets were switched to oxidized: low-tocopherol diets, hepatic α-tocopherol concentration was significantly ( P < 0.05) lowered within 2 weeks. The results highlight the importance of dietary oil quality in modulating tissue α-tocopherol concentrations in African catfish.  相似文献   
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This study investigated the effects of ascorbic acid and α-tocopherol supplementation on semen quality parameters of equine thawed-frozen semen. Semen was divided in seven different treatments in a final concentration of 100 × 106 sperm/mL by using Gent extender containing no supplements (control) and the following supplements with three different concentrations: α-tocopherol (0.5, 1, and 2 mM) and ascorbic acid (0.45, 0.9, and 1.8 g/L). After thawing, all samples were maintained at 37°C, while analyses were performed at 0, 60, and 120 minutes. Evaluation of viability and acrosome status (using Pisum sativum agglutinin conjugated to fluorescein isothiocyanate and propidium iodide), mitochondrial membrane potential (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine [JC-1]), membrane lipid peroxidation (LPO; C11-BODIPY581/591), and stability of the plasmatic membrane (merocyanine 540 and Yo-Pro-1) of each sample was determined by flow cytometry. Relative to the control group, supplementation with α-tocopherol improved (P ≤ .05) postthaw membrane LPO, yet the higher concentrations of ascorbic acid (0.9 and 1.8 g/L, respectively) showed a negative effect on membrane LPO. Neither antioxidant significantly increased (P > .05) the acrosome integrity and mitochondrial membrane potential of frozen-thawed spermatozoa, although supplementation with α-tocopherol and ascorbic acid (0.9 and 1.8 g/L, respectively) had a positive effect on membrane integrity and stability (P ≤ .05). For all semen parameters, the lower concentration of ascorbic acid (0.45 g/L) did not show significant differences (P > .05) compared with the control. In conclusion, α-tocopherol seems to be an efficient antioxidant for reducing the oxidative stress provoked by cryopreservation, decreasing lipid peroxidation on equine spermatozoa.  相似文献   
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大豆α-生育酚的遗传与QTL分析   总被引:1,自引:1,他引:0  
【目的】 通过对大豆α-生育酚进行遗传和QTL分析,研究其遗传机制,定位其主效QTL,为高α-生育酚含量的大豆品种选育奠定遗传学基础。【方法】 以栽培大豆晋豆23为母本、山西农家品种大豆灰布支黑豆(ZDD02315)为父本杂交衍生的447个RIL作为供试群体构建遗传图谱,试验群体及亲本分别于2011年、2012年和2015年夏季在河南省农业科学院原阳试验基地种植,冬季在海南省三亚南繁基地种植。田间试验采取随机区组设计,2次重复。从6个环境中每个家系选取15.00 g籽粒饱满,大小一致的大豆种子,利用高效液相色谱法定性、定量测定样品中的α-生育酚含量。采用主基因+多基因混合遗传分离分析法和WinQTLCart 2.5复合区间作图法,对大豆α-生育酚含量进行主基因+多基因混合遗传分析和QTL定位。【结果】 基于主基因+多基因混合遗传分离分析法,α-生育酚受4对主基因控制,遗传基因分布在双亲中。4对主基因间加性效应值中3对为正值,表明这些基因来源于母本晋豆23;1对为负值,表明该对基因来源于父本灰布支黑豆;4对主基因之间相互作用的上位性效应表现为正值和负值的各有3对,说明不同基因间上位性效应对α-TOC的影响方向并不完全一致。环境因素引起的变异为0.13%—4.05%。表明α-TOC主要受4对主基因影响,受环境因素影响较小。采用WinQTLCart 2.5复合区间作图(CIM)共检测到17个影响α-生育酚的QTL,分布于第1、2、5、6、8、14、16、17共8条染色体中,单个QTL的贡献率8.35%—35.78%,QTL主要表现为加性效应。qα-D1a-1同时在2011年原阳、2012年原阳和三亚、2015年原阳4个环境下检测到,且均定位在第1染色体Satt320—Satt254标记区间19.79 cM处,解释的表型变异分别为12.55%、12.01%和11.89%、12.61%,加性效应值0.119-0.132,增加α-TOC含量的等位基因来自母本晋豆23;qα-A2-1同时在2011年原阳和三亚、2015年原阳3个环境下检测到,且均定位在第8染色体Sat_129—Satt377标记区间44.53 cM处,解释的表型变异分别为23.18%和22.56%、23.01%,加性效应值-0.195—-0.180,增加α-TOC含量的等位基因来自父本灰布支黑豆。qα-D1a-1和qα-A2-1 2个QTL能够稳定遗传。【结果】 α-生育酚最适遗传模型符合4MG-AI,即4对具有加性上位性效应的主基因遗传模型。其遗传主要受4对主基因影响,受环境因素影响较小。检测到α-生育酚的2个稳定主效QTL,Satt320—Satt254和Sat_129—Satt377是共位标记区间。  相似文献   
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随着转基因作物的发展和推广,具有复合性状的转基因作物种植面积逐年增加.传统的转基因复合性状作物具有抗虫和耐除草剂性能,聚合其他性状的转基因作物培育逐渐受到重视.转基因玉米株系BBHTL8-1含有Cry1Ab、Cry3Bb、cp4epsps 、ZmHPT和ZmTMT共5个基因表达框,外源插入片段位于玉米基因组第4染色体,...  相似文献   
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ABSTRACT

The value of fish is largely dependent on fillet size and species but greater value could be obtained by finding commercial uses for the remaining fish frame, particularly fish by-products. Vitamin E and polyunsaturated fatty acids, particularly docosahexaenoic acid (DHA) and eicosapentaenoic (EPA), are of economic importance to the food and pharmaceutical industries and are available for extraction from fish waste. The objective of this study was to compare α-tocopherol levels and the fatty acid profile from several demersal species (cod, ling, saithe and haddock, n = 15) caught in Irish coastal waters over a one-year period (2001). α-Tocopherol levels in samples of liver, viscera and cut-off (any residual flesh from belly flap) were extracted and subsequently measured by high performance liquid chromatography (HPLC). Total fatty acids were extracted and determined by gas chromatography (GC). Results indicated that a-tocopherol levels in liver were higher (P < 0.05) than those in viscera or cut-off. Regardless of species, α-tocopherol levels were found in the following order: liver > viscera > cut-off. In general, α-tocopherol levels were highest in autumn and lowest in spring. Overall, percent free fatty acid levels recorded in liver and viscera samples were higher (P < 0.05) than those in cut-off samples. Percent free fatty acid varied significantly (P < 0.05) with each season, and was generally greater in autumn samples. An inverse relationship was observed between percent fat and moisture levels recorded in this study. The major fatty acids identified in each fish species and each by-product were 16:0 (palmitic), 18:0 (stearic), 18:1 (oleic) 20:5n-3 (eicosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic, DHA). The highest percent of total identified fatty acids were reported in the autumn catch, including the highest EPA and DHA levels. Overall, liver samples had the highest levels of EPA and DHA.  相似文献   
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