GABA、牛磺酸及枸杞子水浸液对青鱼将抗缺氧能力的影响

G ABA质量分数0.5%溶液对青鱼将抗缺氧能力有极显著改善,0.65%溶液对青鱼将抗缺氧能力有显著改善。牛磺酸质量分数0.5%、0.7%溶液对青鱼将抗缺氧有显著改善,0.9%、1.05%、1.25%溶液对青鱼将抗缺氧有极显著改善。适当剂量枸杞子的第1次和第2次热水浸出液明显提高了青鱼将的耐缺氧能力。     

牛磺酸、γ-氨基丁酸对高体鲂皱抗缺氧能力的影响

分别设置5种不同质量分数的牛磺酸、γ-氨基丁酸溶液，在50mL倒置的锥形瓶中，研究了它们对高体鲚皱抗缺氧能力的影响。结果表明，牛磺酸、γ-氨基丁酸均能增强高体鲚皱抗缺氧能力，0．10％和0．30％的牛磺酸溶液对提高高体鲚皱抗缺氧能力有极显著和显著作用；0．15％的γ-氨基丁酸溶液对提高高体鲚皱抗缺氧能力有极显著作用。     

牛磺酸、γ-氨基丁酸对高体鳑鮍抗缺氧能力的影响

分别设置5种不同质量分数的牛磺酸、γ-氨基丁酸溶液,在50 mL倒置的锥形瓶中,研究了它们对高体鳑鮍抗缺氧能力的影响.结果表明,牛磺酸、γ-氨基丁酸均能增强高体鳑鮍抗缺氧能力,0.10%和0.30%的牛磺酸溶液对提高高体鳑鮍抗缺氧能力有极显著和显著作用;0.15%的γ-氨基丁酸溶液对提高高体鳑鮍抗缺氧能力有极显著作用.     

GABA、牛磺酸和pH值影响蝌蚪耐缺氧能力的研究

在水中溶解氧一定的条件下, 将蝌蚪放入50 mL密闭三角瓶内, 观察不同质量分数的牛磺酸、GABA 以及水体不同pH 值对蝌蚪耐缺氧能力的影响。结果显示, 质量分数为0. 4% 的GABA水溶液对蝌蚪耐缺氧能力有极显著改善(P < 0. 01) , 0. 3%的GABA 对蝌蚪耐缺氧能力有显著改善(P < 0. 05)。0. 3%的牛磺酸对蝌蚪耐缺氧能力有极显著改善(P < 0. 01) , 0. 1%、0. 2%、0. 4%、0. 5%的牛磺酸对蝌蚪耐缺氧能力有显著改善(P < 0. 05)。实验证明, GABA、牛磺酸均可提高蝌蚪的耐缺氧能力。而0. 2%的B- 丙氨酸可明显减弱牛磺酸的耐缺氧能力。pH值为5. 4、8. 0时可极显著减弱蝌蚪的耐缺氧能力(P < 0. 01), pH 值为712、7. 7时可显著减弱蝌蚪的耐缺氧能力(P < 0. 05) 。     

牛磺酸、γ-氨基丁酸对鲫抗缺氧能力的影响

研究牛磺酸、γ-氨基丁酸对鲫抗缺氧能力的影响,结果表明质量分数5‰、7‰牛磺酸水溶液对鲫抗缺氧能力有显著(P<0.05)和极显著作用(P<0.01),质量分数3‰γ-氨基丁酸水溶液对鲫抗缺氧有显著作用(P<0.05)。实验证明,γ-氨基丁酸、牛磺酸均可提高鲫的抗缺氧能力。     

GABA、牛磺酸和pH值影响蝌蚪耐缺氧能力的研究

在水中溶解氧一定的条件下,将蝌蚪放入50 mL密闭三角瓶内,观察不同质量分数的牛磺酸、GABA以及水体不同pH值对蝌蚪耐缺氧能力的影响.结果显示,质量分数为0.4%的GABA水溶液对蝌蚪耐缺氧能力有极显著改善(P＜0.01),0.3%的GABA对蝌蚪耐缺氧能力有显著改善(P＜0.05).0.3%的牛磺酸对蝌蚪耐缺氧能力有极显著改善(P＜0.01),0.1%、0.2%、0.4%、0.5%的牛磺酸对蝌蚪耐缺氧能力有显著改善(P＜0.05).实验证明,GABA、牛磺酸均可提高蝌蚪的耐缺氧能力.而0.2%的β-丙氨酸可明显减弱牛磺酸的耐缺氧能力.pH值为5.4、8.0时可极显著减弱蝌蚪的耐缺氧能力(P＜0.01),pH值为7.2、7.7时可显著减弱蝌蚪的耐缺氧能力(P＜0.05).     

不同营养水平的饲粮对产蛋期美国鹧鸪种蛋品质和代谢的影响

采用饲养试验和代谢试验相结合的方法，研究了不同营养水平的饲粮对产蛋期美国鹧鸪种蛋品质和代谢的影响。结果表明，不同营养水平的饲粮对种蛋品质的大多数指标影响不显著（P＞0．05），而对种蛋蛋白高度、哈氏单位等少数指标有显著性影响（P＜0．05），第4组的种蛋蛋白高度最大，为4．73mm，分别比第5、3、2、1组高2．54％、4．44％、5．71％、8．46％，其中第4组与第1、2、3组间有显著差异（P＜0．05），而与第5组差异不显著（P＞0．05）；第4组种蛋哈氏单位为84．66，分别比第5、3、2、1组高1．75％、1．91％、2．41％、3．01％，其中第4组与第1、2组差异显著（P＜0．05），而与第5、3组差异不显著（P＞0．05）。不同营养水平的饲粮对产蛋期美国鹧鸪的代谢也有影响，第4组能量代谢率最大，达76．25％，分别比第3、5、2、1组高1．11％、1．42％、2．09％、2．10％，其中与第1、2组差异显著（P＜0．05），而与第3、5组差异不显著（P＞0．05）；第4组蛋白质日沉积率最高，是79．43％，分别比第1、5、2、3组高1．35％、1．79％、1．88％、2．58％，但各组间差异不显著（P＞0．05）。     

养殖系统中不同水质区域滞留时间差异对海洋青鳉摄食行为、抗胁迫能力和生长的影响

本研究考察养殖系统中不同水质区域滞留时间差异对海洋青鳉(Oryzias melastigma)生长、摄食行为和抗胁迫能力的影响。将养殖系统分成中央区域和角部区域, 设置海洋青鳉在角部区域内滞留的 4 个时间梯度, 分别为 24 h、14.4 h、7.2 h、0 h, 即分别占一昼夜的 100% (P100)、60% (P60)、30% (P30)、0% (P0)。分析不同流场区域的水质差异, 然后比较海洋青鳉在不同流场中的生长、摄食行为和抗胁迫能力。结果显示, 在 28 d 的养殖实验中, 虽然中央区域和角部区域的溶解氧、pH、NO₂ – -N 和 NH₃-N 等水质指标均符合国家渔业水质标准(GB11607-89)要求, 但是随着养殖时间延长, 养殖容器角部区域水质质量逐渐劣于中央区域。所有处理组海洋青鳉的体长和体重均有增加, 但各处理组间的生长差异明显(P0＞P30＞P60=P100)(P＜0.05)。随着鱼体在容器角部区域滞留时间的增加, 其生长速率逐渐下降, 摄食效率降低, 抗胁迫能力(MDA 含量、GSH 和 CAT 活性升高)下降(P＜0.05)。综上所述, 养殖系统内水质的微差异能够影响海洋青鳉的摄食行为、抗胁迫能力和生长速率。因此, 养殖用水质量既要符合国家与行业的相关规定, 还应要求养殖系统内水质保持良好的均匀性。     

十二烷基苯磺酸钠对奥尼罗非鱼免疫毒性的研究

用5种浓度的十二烷基苯磺酸钠（sodium dodeeyl benzene sulfonic，SDBS）浸泡刺激奥尼罗非鱼（Tilapianilotica♀×raurea♂）8周，每2周采血样1次，测定免疫指标。0．05和0．10mg·L^-1组对奥尼罗非鱼的氯化硝基四氮唑兰（nitro blue tetrazolium，NBT）阳性细胞和IgM含量无影响。0．40mg·L^-1组在第8周时，IgM含量显著下降，而NBT阳性细胞突然急剧下降，与对照组相比差异极显著。0．70mg·L^-1组从第4周起，NBT阳性细胞和IgM含量开始减少，第6周时差异显著。1．00mg·L^-1组NBT阳性细胞数在第2周时量就已经有减少，但与对照组相比差异不显著，到第4周时差异极其显著；在第4周时IgM含量有显著差异，第6周后差异极显著。攻毒试验表明，0．40、0．70和1．00mg·L^-1组的死亡率均高于对照组。以上结果表明，当SDBS浓度大于0．40mg·L^-1时，奥尼罗非鱼免疫功能不同程度受到抑制，对NBT阳性细胞和IgM的影响存在着时间与剂量效应。     

基于CRISPR/Cas9系统构建青鳉突变体

青鳉是研究基因功能、器官发生和发育机制的模式生物之一，基因编辑技术已在青鳉中得到广泛应用，但利用CRISPR/Cas9技术构建青鳉突变体的详细过程还未见报道。为了完整详细地阐明青鳉突变体的构建过程，实验以青鳉Olpax6.1基因的敲除为例，首先利用ChopChop 网站设计获得 Olpax6.1基因gRNA的靶点；其次通过PCR扩增和质粒酶切分别获得gRNA和Cas9 mRNA体外转录的模板，并通过体外转录合成gRNA和Cas9 mRNA；再将Cas9 mRNA和gRNA混合进行青鳉胚胎显微注射获得突变F₀；最后利用PCR、T7 Endonuclease Ⅰ酶切和Sanger测序筛选F₀与野生型杂交的子代获得相同突变类型的F₁，进而将相同突变的F₁进行杂交并筛选其子代，获得青鳉 Olpax6.1 敲除的纯合突变体，纯合突变体表现出眼部发育畸形的经典表型。本研究为青鳉突变体的构建提供详细完整的实验方案，同时也为其他鱼类突变体的构建提供技术参考。     

母猪胎衣不下的病因与防治要点

猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。     

Estimation of variation of virulence of Renibacterium salmoninarum by survival analysis of experimental infection of salmonid fish

The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms.     

水硬度对七彩神仙鱼幼鱼发育的影响

采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。     

虎斑乌贼受精卵卵黄营养成分分析

本实验对虎斑乌贼受精卵卵黄的营养成分进行分析,旨在探讨其幼体的营养需求量,为其幼体配合饲料研制提供参考数据。随机选取大约800个虎斑乌贼受精卵的卵黄,采用国家标准方法测定其水分、灰分、粗蛋白质、粗脂肪、氨基酸、脂肪酸和矿物元素含量。结果表明:1)虎斑乌贼受精卵卵黄中粗蛋白质含量为76.33%(干重基础);总氨基酸(TAA)和必需氨基酸(EAA)含量分别为71.22%和32.38%(干重基础),EAA/TAA为45.46%,氨基酸中以谷氨酸(Glu)含量最高(9.97%),必需氨基酸中亮氨酸(Leu)含量最高(7.58%)。2)其粗脂肪含量12.71%(干重基础);共检出17种脂肪酸,包括8种饱和脂肪酸(SFA)、5种单不饱和脂肪酸(MUFA)和4种多不饱和脂肪酸(PUFA),SFA、MUFA和PUFA分别占脂肪酸总量的43.47%、7.54%和49.25%,其中以DHA含量最高,达32.80%,EPA含量为7.70%,DHA/EPA为4.26。3)检测出Na、K、Ca、Mg、Sr、Mn、Fe、Cu、Zn、Al和As 矿物元素,微量元素中富含Zn、Al和Fe,含量分别为 0.77、0.71和0.43 mg/kg(鲜重基础)。由此可见,卵黄具有高蛋白、低脂肪,富含n-3PUFA的特点;虎斑乌贼幼体饲料中蛋白质需求量参考值为76.33%;氨基酸需求量参考值,如赖氨酸(Lys)为5.49%,蛋氨酸(Met)为2.63%;脂肪的需求量参考值为12.71%,DHA为4.17%,EPA为0.98%;微量元素需求量参考值,如Zn为2.77 mg/kg,Cu为0.19 mg/kg(干重基础)。     

Characterization of protease inhibitors of seminal plasma of cyprinids

Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season).     

鱼类热忍耐温度研究进展

The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect: (1) The key parameters of temperature of thermal tolerance in fishes; (2) The influence factors of temperature of thermal tolerance in fishes; (3) The research methods of thermal effect of fishes; (4) The evaluation of effects of thermal pollution on fishes, especially, with the coastal power station will be‘built in China recent years, the effects of thermal discharge water on the marine fisheries resource wered iscussed.     

Histopathology of respiratory organs of certain air-breathing fishes of India

Air-breathing fishes have evolved bimodal respiratory mechanisms for exploitation of water (through gills and highly vascularized skin) as well as atmospheric air (through aerial respiratory organs, ABO). Mucous cells in these respiratory organs of variously stressed fishes exhibit periodic fluctuations in their density and staining properties. The main types of damage in the gills include congestion of blood capillaries (BLCs), periodic lifting and sloughing of respiratory epithelia of the secondary lamellae causing haemorrhage, extensive fusion of secondary lamellae and hyperplasia of the respiratory epithelia due to uncontrolled regeneration leading to asphyxiation, altered excretion, and death of the fish. Haemolysis has also been observed following lead exposure. The damage in the ABO of Heteropneustes fossilis includes sloughing of the epithelial cells, leading to haemorrhage causing decreased red blood corpuscles density and degeneration of the secondary gill lamellae with reduced respiratory area. Subsequent hyperplasia of the respiratory epithelia and fusion of gill lamellae increase the respiratory barrier distance. The BLCs often bulge out and protrude into the lumen, bringing blood nearer to air. The ladder-like pillar cell (PLC)-BLC components of the gill lamellae frequently collapse. Damage to the ABO of Channa striata is less severe. Often haemorrhaging due to bursting of extensively stretched BLCs causes aerial respiratory failure. Chloride cells of the ABOs also show hyperplasia. While the highly mucogenic epidermis of C. striata shows less damage, the epidermis of Clarias batrachus and H. fossilis shows severe wear and tear, sloughing, and haemorrhage. Side-by-side regeneration continues, causing altered histomorphology of the epidermis. The different gland cells also show periodic fluctuations in their density and staining. The dermis also shows severe damage with loosening of their connective tissue fibres. These fibres give stronger reactions for sulfated mucin that not only retain additional water molecules for continuance of skin breathing, but also bind the toxic ambient pollutants.     

浅谈船舶干舷的作用

近几年．在唐山沿海发生的渔船海难、海损事故经统计表明呈增多趋势。这与出海作业渔民的安全意识不强有很大关系．渔民为了挣取更多的效益，在海上，超抗风浪等级作业且人为地增加船的不规范载荷．造成船的储备浮力损失，酿成恶果。笔者认为．在渔船设计建造中，留取的干舷对渔船作业的安全性起相当重要的作用，必不可少。 一、储备浮力的重要性 所谓储备浮力就是自船舶设计水线至水密甲板的水密部分体积，其大小与干舷相关．于舷大则储备浮力大，干舷的重要性就在于能够使船在海中保持正常的浮性和安全。再者，在设计建造渔船时，为了改善…     

脂质体介导的鲫CAB细胞转化及转化细胞的核移植

采用脂质体法成功地使gfp基因转入鲫囊胚细胞株CAB细胞基因组，获得了具有G418抗性的细胞。以转化细胞为供体，银鲫卵为受体，核移植得到了转基因的囊胚和原肠胚；并发现4℃处理细胞24h能显著改善核移植胚胎的发育。     

牙鲆刺激隐核虫病的防治

2005年七、八月份,乐亭、滦南一带多家工厂化牙鲆养殖场发生刺激隐核虫病,此种病虫害发病急、传染快、死亡率高。发生过该病的养殖场牙鲆死亡率一般都在50％～80％之间,这种病害给牙鲆养殖业带来很大损失。