共查询到19条相似文献，搜索用时 296 毫秒
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二噁英(dioxin)所以被称为"世纪之毒",因之是危害极大的环境激素,致畸、致癌和突变性强,可通过食物链富集进入鱼、人和其他动物体内,并在脂肪中积蓄,对机体健康构成严重威胁。其中尤以2,3,7,8-四氯二苯并-对-二噁英(2,3,7,8-tetrachlorodibenzo-p-dioxin,TCDD)的毒性最强,引起了全球的高度关注。文中着重综述TCDD对鱼类胚胎发育的影响、机理及目前预防TCDD对鱼类胚胎发育影响的研究进展,旨在更好地为研究TCDD对鱼类胚胎发育的影响、机理及预防措施提供参考。 相似文献
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农业环境是指客观物质世界中与农业生物发生相互关系影响的各种环境因素的总和。通常指农作物、森林、畜禽、鱼类和其他经济水生生物生长繁殖所需要的土壤、水体、空气和阳光等自然条件。 相似文献
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二[口恶]英是一类氯代含氧三环芳烃类持久性有机污染物,因为其特有的化学和物理特性,很容易在食物链中积累。二[口恶]英包含多氯二苯并对二[口恶]英(PCDDs)和多氯二苯并呋喃(PCDFs)两大类,其中2,3,7,8-四氯二苯并对二[口恶]英(TCDD)是毒性最强的一种。本文主要就生鲜乳中PCDDs和PCDFs的含量、来源及其中TCDD的毒性作用及其机理进行概述,为相关研究提供一定参考。 相似文献
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环境胁迫因子对鱼类免疫功能的影响 总被引：4，自引：0，他引：4
环境胁迫因子对鱼类免疫功能的影响李彦江育林（中国科学院水生生物研究所，武汉４３００７２）与人类和其他脊椎动物一样，鱼类也是通过其免疫系统识别和消除异物，行使防御、自身稳定和免疫监督三大功能的。鱼病的发生是鱼体、病原和环境三者相互作用的结果。由于鱼类是... 相似文献
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提高化肥养鱼的关键技术 总被引：1，自引：0，他引：1
一、化肥养鱼的原理与特点 化肥养鱼的原理可以简单地概括为:通过施肥向水体补充营养物质,促进浮游植物大量繁殖,并使水生维管束植物、固着生物、自养细菌等数量增加,在满足滤食性鱼类摄食的同时,也为吃食性鱼类提供部分食料。化肥养鱼与农田施肥相比,具有以下特点: (一)作用机制复杂且具有双重效果 施入水中的化肥不能作为鱼类的直接饵料,而是为鱼类的基础饵料绿色植物提供养分。这些绿色植物在营养物质丰富的情况下大量生长繁殖后,一部分被鱼类摄食成为直接饵料,另一部分则被浮游动物、底栖动物和其他水生动物摄食,间接为鱼类提供… 相似文献
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本试验旨在研究多不饱和脂肪酸比例对扬州鹅生长阶段肉品质的影响。在饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸1∶1∶1的前提下,通过调节日粮中不同的ω-6/ω-3多不饱和脂肪酸比例,设置3∶1、6∶1、9∶1、12∶1四组进行扬州鹅饲养试验。结果表明:(1)ω-6/ω-3比例对雏鹅的不同生长阶段腿肌的嫩度、42日龄滴水损失均无显著差异性影响(P0.05);(2)56日龄时12∶1组腿肌pH值显著高于比例为3∶1(P0.05),12∶1的胸肌pH值显著高于3∶1组(P0.05),而在此日龄内其他比例间及其他日龄不同比例间均无显著差异性(P0.05);(3)在42日龄时12∶1组肌肉失水率显著高于9∶1和3∶1,在70日龄时12∶1显著高于3∶1(P0.05)。结论:ω-6/ω-3PUFA比例对不同生长阶段扬州鹅肌肉品质有一定的影响,以12∶1组各阶段肌肉pH值和失水率较高,但对肌肉嫩度的影响不大。 相似文献
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多不饱和脂肪酸对鱼类免疫与成活的影响及机理 总被引：2，自引：0，他引：2
多不饱和脂肪酸(PUFAs)是具有重要生物学功能的独特生物活性物质,是神经和其他细胞膜的重要组分,花生碳四烯酸(AA)和二十碳五烯酸(EPA)还产生类二十烷酸调节机体炎症、T淋巴细胞和B淋巴细胞功能.PUFAs通过影响机体脂类代谢、基因表达、细胞膜功能、机体免疫及血液生化特性等对鱼类生长、发育、免疫和存活发挥重要的作用.本文主要综述PUFAs对鱼类免疫的影响与机理,探讨PUFAs通过提高免疫力而增加鱼类特别是仔稚鱼成活率的调节,以便进一步深入研究PUFAs,更好地利用PUFAs,调控提高鱼类免疫力、生长、发育和成活. 相似文献
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我国的水电资源丰富,但水电开发也造成了河流环境结构和水文情势的改变,对河流水生生态系统形成了破坏,带来很多生态影响,其中对鱼类的影响主要表现为阻隔了鱼类洄游通道,影响鱼类基因的自然交流,导致遗传质量下降,甚至近亲繁殖。本文就黄河白银段水利水电站项目的实施对水产种质资源保护区内水生生物及其水产养殖的影响提出了相应的对策及建议。 相似文献
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J M Spitsbergen K A Schat J M Kleeman R E Peterson 《Veterinary immunology and immunopathology》1986,12(1-4):263-280
Chlorinated dioxins, as typified by the most potent isomer, TCDD, are immunosuppressive in mammalian species and can enhance the susceptibility to a number of diseases. In recent years chlorinated dioxins have been detected in fish in many freshwater and marine habitats. Thus far, the effects of these chemicals on the immune responses of fish have not been examined. We studied the influence of TCDD on the defense mechanisms of rainbow trout. Yearling trout were injected intraperitoneally with the vehicle, 0.1, 1.0 or 10 micrograms/kg of TCDD. Interactions with the humoral immune response to sheep red blood cells (SRBC) were assessed by the Jerne plaque assay using head kidney and spleen leukocytes. Serum antibody was measured by complement-mediated lysis of SRBC in a chromium release assay. Effects of TCDD on the cellular immune responses were evaluated by the response of thymic and splenic lymphocytes to Con A and PWM. In addition, the phagocytic activity of peritoneal macrophages was examined in vitro. Trout which received 0.1 or 1.0 micrograms/kg TCDD remained clinically normal, and defense mechanisms were unaltered in these fish. Trout which received 10 micrograms/kg of TCDD became hypophagic and exhibited fin necrosis, ascites and suppression of hematopoiesis. In this treatment group, Con A-induced blastogenesis of thymic and splenic lymphocytes was not significantly changed, however, suppression of the PWM-induced response of splenic lymphocytes occurred. No statistically significant alterations occurred in humoral immune responses, and phagocytic activity of peritoneal macrophages was not decreased. The dose-response curve for various biologic effects of TCDD in the rainbow trout appears different from that in sensitive mouse strains. The 30-day, single-dose, parenteral LD50 for TCDD in the C57BL mouse is 100 micrograms/kg, and TCDD suppresses both cell-mediated and humoral immune responses at 1-2 micrograms/kg in this mouse strain. In the rainbow trout, however, immunosuppression was evident only at doses of TCDD approaching the 80-day, single-dose, parenteral LD50 of 20 micrograms/kg. 相似文献
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Yamazaki K Teraoka H Dong W Stegeman JJ Hiraga T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(9):829-833
Cytochrome P450 1A (CYP1A) is well known for being induced by aromatic hydrocarbons, including 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD). We determined the complete cDNA sequence of a CYP1A open reading frame with both 5'- and 3'-ends in zebrafish (zfCYP1A), a useful model for environmental toxicology. zfCYP1A shows high percentage identity with CYP1As of mammals, domestic fowl and xenopus (51.9-60.4%), as well as the other fish species (63.8-89.2%). As revealed by in situ hybridization and immunohistochemistry, zfCYP1A was scarcely detected in control embryos but was markedly induced by TCDD especially in heart, vascular endothelial cells, intestinal epithelium, pronephros and outer integument in both prehatched and hatched embryos. These expression patterns are consistent with possible involvement of zfCYP1A in TCDD-induced toxicities. 相似文献
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Earlier and present experiments have shown detrimental influence of sulphuric acid preserved fish in mink feed on production parameters, early kit growth and kit mortality. Comparison of the production parameters with clinical-chemical parametres and pathological-anatomical findings give a picture of the tolerated amount of sulphuric acid preserved fish silage in the mink feed during different production periods. It seems that the animals tolerate only small amounts of sulphuric acid preserved fish silage (5-8 per cent) in the total feed during the stress periods of reproduction, lactation and early kit growth but higher amounts (20-30 per cent) during late growth period, where the need of feed is high. 相似文献
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本试验旨在研究饲料中添加氧化鱼油对黄颡鱼(Pelteobagrus fulvidraco)生长性能、体成分、血清生化指标和血清、肝脏抗氧化指标的影响以及添加精氨酸对其的干预作用。选取初始体重为(4.41±0.05)g的健康黄颡鱼幼鱼600尾,随机分为6组,每组4个重复,分别投喂含2.5%新鲜鱼油(FF组)、1.5%新鲜鱼油+1.0%氧化鱼油(FO1组)、0.5%新鲜鱼油+2.0%氧化鱼油(FO2组)、2.5%新鲜鱼油+0.48%L-精氨酸盐酸盐(FFA组)、1.5%新鲜鱼油+1.0%氧化鱼油+0.48%L-精氨酸盐酸盐(FOA1组)、0.5%新鲜鱼油+2.0%氧化鱼油+0.48%L-精氨酸盐酸盐(FOA2组)的6种饲料,投喂期为56 d。结果显示:在FF、FO1、FO2组中,随着氧化鱼油添加量的增加,黄颡鱼的增重率、特定生长率和蛋白质沉积率均逐渐降低,饲料系数和摄食率均逐渐升高,均在FO2组达到极值,与其他2组差异达到显著水平(P0.05);氧化鱼油饲料添加精氨酸后,在FFA、FOA1、FOA2组上述指标没有产生显著性差异(P0.05),其中FOA1、FOA2组的增重率分别比FO1、FO2组升高3.0%和9.9%。双因素方差分析结果显示,氧化鱼油对黄颡鱼增重率和摄食率的影响达到显著水平(P0.05),氧化鱼油与精氨酸对黄颡鱼特定生长率、蛋白质沉积率和饲料系数的影响存在交互作用(P0.05)。FO1组肝体比显著低于FF组(P0.05),FO2组肠体比与FFA、FOA2组相比显著降低(P0.05),氧化鱼油与精氨酸对黄颡鱼肝体比的影响存在交互作用(P0.05)。FOA1组全鱼粗脂肪含量与FO1组相比显著降低(P0.05)。在FF、FO1、FO2组中,随着氧化鱼油添加量的增加,黄颡鱼血清总抗氧化能力(T-AOC)逐渐降低,FO2组显著低于FF组(P0.05);氧化鱼油饲料添加精氨酸后,黄颡鱼血清T-AOC分别升高77.0%(FOA1组vs.FO1组)和137.4%(FOA2组vs.FO2组),其中后者达显著水平(P0.05)。双因素方差分析结果显示,氧化鱼油对血清丙二醛(MDA)含量的影响达到显著水平(P0.05),氧化鱼油和精氨酸对黄颡鱼血清T-AOC的影响存在交互作用(P0.05)。结果表明,在饲料中添加一定量的氧化鱼油会抑制黄颡鱼的生长并降低血清的抗氧化能力,但添加一定量的精氨酸可以缓解氧化鱼油对黄颡鱼生长的抑制作用,并增强其机体的抗氧化能力。 相似文献
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不同蛋白质源部分替代鱼粉对褐点石斑鱼幼鱼生长性能、体组成以及血清生化指标的影响 总被引：3，自引：0，他引：3
本试验旨在研究不同蛋白质源部分替代鱼粉对褐点石斑鱼幼鱼生长性能、体组成以及血清生化指标的影响。配制5组等氮等能饲料,对照组饲料(D1)含68%的鱼粉,试验组饲料(D2～D5)是在对照组饲料的基础上分别用豆粕替代10%的鱼粉、豆粕替代20%的鱼粉、啤酒酵母替代10%的鱼粉、玉米蛋白粉替代10%的鱼粉。选取体重在15 g左右的褐点石斑鱼幼鱼180尾,随机分为5组,每组3个重复,每个重复12尾。试验期为8周。结果表明:在生长性能方面,与对照组相比,D2、D3组的增重率、摄食率、特定生长率、粗蛋白质表观消化率差异不显著(P>0.05),而D4、D5组的上述指标均显著降低(P<0.05)。与D2、D3组相比,D4组的特定生长率显著降低(P<0.05),肝体指数显著升高(P<0.05);D5组的摄食率、特定生长率、蛋白质效率和粗蛋白质表观消化率显著降低(P<0.05),饲料系数、肝体指数显著升高(P<0.05)。在体组成方面,D5组全鱼和肌肉中粗蛋白质含量显著低于对照组和D2、D3组(P<0.05);D4组肌肉中粗脂肪含量显著低于对照组和D2组(P<0.05)。在血清生化指标方面,D3组血清总蛋白、球蛋白、葡萄糖含量显著低于对照组(P<0.05),而白球比显著高于对照组(P<0.05);对照组、D4组血清甘油三酯含量显著高于D3、D5组(P<0.05);各组间血清谷丙转氨酶和谷草转氨酶活性没有显著差异(P>0.05)。由此得出,作为鱼粉的替代品,豆粕比啤酒酵母和玉米蛋白粉能更好地满足褐点石斑鱼幼鱼的营养需求;从主要生长指标不受影响的角度考虑,褐点石斑鱼幼鱼饲料中可以用豆粕替代20%的鱼粉。 相似文献
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Ohyama K Ohta M Sano T Sato K Nakagomi Y Shimura Y Yamano Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):619-625
We have analyzed the effects of low-dose transplacental and lactational exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gene expression relating to the dioxin and sexual hormone cascade, and demonstrated the effects on testicular growth and sexual maturation in male offspring rats. TCDD (10 ng/kg) was administered to dams on Days 7 and 14 of gestation, and on Days 0, 7 and 14 after delivery. Gene expression of cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) in the liver of 17-day-old rats was significantly increased compared with controls. Furthermore, expression of estrogen receptors (ER)alpha and ERbeta was significantly increased at 17 and 42 days old, respectively in the testis of TCDD-administered rats compared with controls. Although testicular weight and the seminiferous tubule diameter were increased in 17-day-old rats, there was no difference in the number of germ cells between TCDD-treated and control animals. The expressions of androgen receptor and inhibin subunit genes were not significantly changed. These findings suggest that low-dose exposure of TCDD leads to unusual development of the testis by perturbation of steroid hormone homeostasis. 相似文献
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Modulation of the fish immune system by hormones 总被引：19，自引：0，他引：19
Immune-neuroendocrine interactions in fish, as in mammals, have become a focus of considerable interest, with the modulation of immune responses by hormones receiving particular attention. Cortisol, growth hormone (GH), prolactin (PRL), reproductive hormones, melanin-concentrating hormone (MCH) and proopiomelanocortin (POMC)-derived peptides have all been shown to influence immune functions in a number of fish species. This review summarises the known effects of these hormones on the fish immune system, as well as the often complex interactions between different hormones. The possible implications for fish health, with respect to aquaculture and the changes in immunocompetence that take place during different stages in the fish life cycle are also discussed. 相似文献
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饲料牛磺酸水平对不同生长阶段斜带石斑鱼幼鱼生长性能和体成分的影响 总被引：2，自引：0，他引：2
本试验旨在研究饲料牛磺酸水平对不同生长阶段斜带石斑鱼幼鱼生长性能和体成分的影响。以酪蛋白和明胶为蛋白质源,配制牛磺酸水平分别为0(D1)、0.5%(D2)、1.0%(D3)和1.5%(D4)的试验饲料。将初始体重为(13.85±0.25)g斜带石斑鱼幼鱼随机分为4组,每组4个水族箱(体积为120 L),每箱放养25尾。试验鱼每天投喂饲料2次至表观饱食,养殖周期84d,分别在饲喂的第28、56和84天称重、取样。试验第1~28天为第1个生长阶段,第29~56天为第2个生长阶段,第57~84天为第3个生长阶段。结果表明:在每个生长阶段下,牛磺酸添加组(D2、D3和D4组)试验鱼的增重率、特定生长率、摄食率和饲料效率均显著高于未添加牛磺酸组(D1组)(P0.05),且D3组试验鱼的增重率显著高于其他牛磺酸添加组(第3个生长阶段的D4组除外)(P0.05)。在同一饲料牛磺酸水平下,第1个生长阶段试验鱼的增重率、特定生长率、摄食率和饲料效率均显著高于第2个和第3个生长阶段(P0.05)。在饲喂至第28、56和84天时,各牛磺酸添加组试验鱼的肝体比和脏体比均显著低于未添加牛磺酸组(P0.05),肥满度则与未添加牛磺酸组无显著差异(P0.05)。在同一饲料牛磺酸水平下,饲喂至第56和84天时的肝体比和脏体比均显著低于饲喂至第28天时(P0.05)。饲喂至第84天时,各牛磺酸添加组鱼体的粗蛋白质含量显著高于而粗脂肪含量显著低于未添加牛磺酸组(P0.05)。上述结果表明,饲料中维持一定水平的牛磺酸有利于斜带石斑鱼幼鱼的生长,饲料牛磺酸不足或过多均不利于其生长。饲料中添加牛磺酸降低斜带石斑鱼幼鱼体脂沉积而增加体蛋白质沉积。以增重率为评价指标,通过回归分析得到3个生长阶段斜带石斑鱼幼鱼饲料的适宜牛磺酸水平分别为1.20%(第1个生长阶段)、1.08%(第2个生长阶段)、1.00%(第3个生长阶段)。斜带石斑鱼幼鱼对牛磺酸的需要量随鱼龄的增长而下降。 相似文献