孟家段水库饵料植物与鲢、草鱼鱼产力

报道子孟家段水库铒料植资源状况,并据此推算了植食性鱼鲢、草鱼的鱼产力。该水库鲢平均鱼产力为85kg/hm^2,草鱼仅在下库形成产量,鱼产力为57kg/hm^2。     

溪口水库饵料生物现状及鱼产力的评估

溪口水库库周山地面积多，植被较好。水库集雨面积为2300平方公里，最高水位淹没面积为44．7平方公里，库容达3．7亿方。正常养殖面积44700亩，最大水深25米，平均10米左右。     

渭河流域陕西段典型水库鱼产力及鲢、鳙放养量估算

于2014年6-8月对渭河流域陕西段4座水库的浮游生物和初级生产力进行了调查,根据调查结果测算了各个水库的鱼产力和鲢鳙放养量。结果显示,4座水库浮游植物种类共鉴定出8门40种属,密度为12.00×10~4~132.50×10~4个/L,生物量为0.394 4~2.767 0mg/L;浮游动物的密度为50~2 180个/L,生物量为0.205 7~1.852 0mg/L;初级生产力(水柱平均日毛生产量)为0.405 3~2.206 5mg(O_2)/(m~2·d)。基于浮游生物的鱼产力为鲢鱼32.55~230.70kg/hm~2,鳙鱼46.28~231.60kg/hm~2;基于初级生产力计算的鲢鱼产力为26.23~142.28kg/hm~2,鳙鱼为14.75~80.31kg/hm~2。各个水库鲢鳙的合理放养量分别为98.13~621.63kg/hm~2、48.83~249.54kg/hm~2。     

孟家段水库鲢、鳙的生长及提高鱼产量措施

孟家段水库渔获鲢鳙中,鲢年龄组成不合理,5～7龄鱼占其总尾数67%。鲢、鳙生长较慢。应加大放养规格至13～14cm,降低放养量至每年2.5万kg,鲢鳙比例调整为3:7,加大对凶猛的捕捞力度。     

岩滩水库初级生产力和鱼产力的调查研究

1996年1月、10月及1997年5月，我们对岩滩水库的初级生产力进行了3次调查，结果表明，岩滩水库建成后，其初级生产力与建库前相比有大幅度增加，并由原来的贫营养型转化为中营养型水库。本对该水库浮游植物平均年产量及鲢鳙鱼产力进行了评估。     

峰头水库鱼产力资源调查

峰头力库是一座以灌溉主为的大型水库，有养鱼面积６３３．３ｈａ。库水总氮含量０．７５ｍｇ／Ｌ，总磷０．０３１ｍｇ／Ｌ，浮游植物年平均数量２７．２万个／Ｌ，生物量３．７９ｍｇ／Ｌ；浮游动物数量１１５１个／Ｌ，生物量３．０３ｍｇ／Ｌ；底栖动物数量１４５７个／ｍ＾２，生物量９５４．４ｇ／ｍ＾２，初级生产力为２．６６ｇＱ２／ｍ＾２·ｄ，该水库为中营养型水库，年鱼产力１７．６７万ｋｇ。     

碧流河水库底栖动物及其鱼产力的研究

先后对碧流河水库的5个断面、10个采样点的底栖动物进行调察,采到寡毛类3种,水生昆虫2种。底栖动物的平均密度为335.6个/m2,平均生物量为2.013 g/m2。寡毛类的数量最多,软体动物贫乏。克拉泊水丝蚓和羽摇蚊幼虫是该库的2个优势种。底栖动物种群结构简单、种类单一。还对底栖动物的鱼产潜力进行了估算,其值为8.1 kg/hm2。     

沙河水库加固扩建后的水质和鱼产力

扩建蓄水初期,铵氮等营养盐明显增高,裸藻门的种类增加,大型浮游动物数量较1984年前逐年明显减少。讨论了理化生物条件变化原因,对鱼产力进行了评估,并提出对策。     

无效负载率的概念和水库鱼产力的推算

影响水库鱼产力的主要因素可分为两个方面:一是营养元素丰度、初级生产力大小和饵料生物多寡;二是鱼类区系组成和鱼类种群的年龄结构。我国以往的研究工作主要是根据初级生产力或浮游生物量及其P/ B系数对鱼产力进行估算。但我国大部分水库鲢和鳙的产量     

坤龙水库浮游生物调查及鱼产力分析

共检出浮游植物8门43属,生物量为20.57 mg/L。浮游动物生物总量为19.48 mg/L,大型浮游动物中晶囊轮虫和剑水溞为优势种类。水库总鱼产力1 098.73 kg/hm2。属富营养型水库,库水营养盐丰富,有利于浮游生物的生长繁殖。提出了持续发展水库渔业的对策。     

彭泽鲫(♀)与黑龙江野鲤(♂)的杂交利用研究

以彭泽鲫为母本、黑龙江野鲤为父本进行杂交,将杂交一代(F1)的生长速度、抗病力、群体产量、经济效益、同工酶、生物学性状等与双亲进行对比试验。结果表明,杂交一代(F1)具有明显的优势,其生物学性状及同工酶谱与母本彭泽鲫相似。     

Upper lethal and rearing temperatures for juvenile common carp, Cyprinus carpio L., and silver carp, Hypophthalmichthys molitrix (Valenciennes)

Abstract. The ultimate upper lethal temperature (UULT) was 43.0 or 46.0°C for common carp and 43.5 or 46.5°C for silver carp, depending on the method of calculation. The influence of fish age on lethal temperature values was low. Using the relationship between the UULT and the optimum growth temperature the latter was calculated as being 38°C for common carp and 39°C for silver carp. No significant differences were found in survival of fish reared at lower and higher temperatures when proper food was used.     

Plasma vitellogenin levels in male common carp Cyprinus carpio and crucian carp Carassius cuvieri of Lake Kasumigaura

In order to investigate the possible influence of estrogenic environmental endocrine disruptors on the reproductive activity of fish in Lake Kasumigaura, plasma levels of vitellogenin (VTG), a biomarker of estrogen exposure, were measured in wild and cultured male common carp Cyprinus carpio and wild crucian carp Carassius cuvieri . Testicular histology and plasma steroid hormone levels were also examined. Fish were collected from June 1998 to August 1999. Plasma VTG levels in most fish examined were below a detection limit (40 ng/mL) throughout the sampling period, and a small amount of VTG (43.5 ng/mL–1680 ng/mL) compared to that in females was detected in some fish. Active spermatogenesis in the testis and increased levels of plasma sex steroids were observed in most of the fish examined. Thus, no marked influence of estrogenic chemicals was detected in the reproductive activity of male common carp and crucian carp in Lake Kasumigaura collected from the sampling sites in the present investigation.     

Changes in the nutritional parameters of muscles of the common carp (Cyprinus carpio) and the silver carp (Hypophthalmichthys molitrix) following environmental exposure to cyanobacterial water bloom

The present study evaluated the effect of naturally developing cyanobacteria on the composition of muscles of two commercially important freshwater fish species. Fish were exposed to cyanobacterial biomass including Microcystis aeruginosa and Microcystis ichthyoblabe for 4 weeks. Then, they were transferred to dechlorinated potable water without any cyanobacteria for another 4-week period, thus modelling their preparation for consumers. Samples of muscles were collected every week during exposure and subsequent stay in dechlorinated potable water. The cyanobacterial water bloom of 3.9–6 × 10⁵ cells mL⁻¹ (133–383 μg g⁻¹ of total MC DW) induced statistically significant effects only in the content of fatty acids ( P <0.05; P <0.01) in the common carp ( Cyprinus carpio ), while all studied parameters including the content of dry matter and fat ( P <0.01), proteins ( P <0.05), fatty acid composition ( P <0.05; P <0.01) and some amino acids ( P <0.05) were affected in the silver carp ( Hypophthalmichthys molitrix ). This study has shown that cyanobacteria in the environment of commercially produced fish may decrease the dietetic value of fish muscles.     

Colouring ornamental fish (Cyprinus carpio and Carassius auratus) with microalgal biomass

Koi carp and goldfish value increases with intensity of skin colour, which is an important quality criterion. Fish cannot fully synthesize their own carotenoid colourings and these must therefore be included in their diet. Two trials were undertaken to investigate skin colour enhancement in ornamental species (i.e. three chromatic varieties of koi carp (Cyprinus carpio), namely Kawari (red), Showa (black and red) and Bekko (black and white) and goldfish (Carassius auratus)) by feeding a dietary carotenoid supplement of freshwater microalgal biomass [Chlorella vulgaris, Haematococcus pluvialis, and also the cyanobacterium Arthrospira maxima (Spirulina)], using a diet containing synthetic astaxanthin and a control diet with no colouring added for comparison. In the first trial, five homogeneous duplicate groups of 25 juvenile koi carp (C. carpio) (initial mean body weight 24.6 ± 0.7 g) were fed, for 10 weeks, one of the four diets containing 80 mg colouring/kg diet. In the second trial, this procedure was repeated for five homogeneous duplicate groups of 25 goldfish (C. auratus) (initial mean body weight of 0.9 ± 0.1 g). Initial and final samples of skin along the dorsal fin were withdrawn, from five fish per group, for subsequent analysis of total carotenoid content (spectrophotometric analysis), and red hue (colorimetric analysis, CIE (1976) L* a* b* colour system). Growth and feed efficiency were not significantly different between groups administered by the various dietary treatments. In both trials, dietary carotenoid supplementation increased total skin carotenoid content. The more efficient colouring for koi carps was found to be C. vulgaris biomass, providing both maximum total carotenoid deposition and red hue for the three chromatic koi carp varieties studied, and particularly for the kawari variety. For goldfish the best colouring obtained, as ascertained by total carotenoid content, was also achieved using C. vulgaris biomass, and red hue was maximum when using H. pluvialis biomass.     

镉暴露对鲢幼鱼游泳行为影响的研究

为了探讨水体镉(Cd)污染对鱼类的生态毒理效应,在实验室条件下,测定了不同浓度Cd(0、0.36、0.73、1.09和1.46 mg/L)暴露对鲢(Hypophthalmichthys molitrix)幼鱼半致死浓度、组织(肝、鳃、肌肉)Cd累积量、相对临界游泳速度(Ucrit)、以及耗氧率(MO_2)的影响。结果显示:Cd暴露导致重金属在幼鱼组织中累积,与对照组比较,Cd在鳃和肌肉中累积量差异不显著;肝脏中累积量差异显著,暴露浓度为0.73 mg/L时肝脏中镉累积量最高。鲢幼鱼相对临界游泳速度随着Cd暴露增加显著降低,浓度为1.46 mg/L时Ucrit为对照组的69.75%。临界游泳速度与鳃和肌肉组织中镉累积量呈显著负相关,相关系数分别为-0.96(P=0.01)和-0.90(P=0.04)。Cd暴露导致鲢幼鱼耗氧代谢范围增加,暴露浓度为0.73 mg/L时耗氧代谢范围较对照组增加了19.32%。低浓度Cd暴露导致鳃和肌肉损伤,并引起鲢幼鱼游泳过程中耗氧代谢效率降低,有氧运动能力和游泳能力下降。     

池塘生态养殖技术对鲫鱼肌肉品质的影响

为深入研究池塘生态养殖对鲫鱼肌肉品质的影响,实验比较了生态养殖模式(ST)与高密度养殖模式(GM)下鲫鱼肌肉的营养成分、质构特征及组织形态。结果表明:ST肌肉的粗蛋白、粗脂肪显著高于GM(P0.05),p H值显著高于GM(P0.05);肌肉中共检测到16种氨基酸,其中ST肌肉的氨基酸总量、必需氨基酸总量、非必需氨基酸总量及风味氨基酸总量显著高于GM(P0.05);肌肉质构特征分析指出两者存在一定差异,但不明显;肌肉组织形态显示ST较GM的肌纤维直径更小,肌纤维密度更大。因此,鲫鱼在生态养殖模式下营养价值和肉质品质均能得到显著提高。     

银鲫多核苷酸重复微卫星的序列同源性分析

应用磁珠富集法开发银鲫的三、四核苷酸重复的微卫星。生物素探针分别为Probe-(TGA)8,Probe-(AGAC)8,Probe-(GATT)8,结果得到4740个菌落。结合同位素放射法进行二次筛选,获得652个阳性克隆(阳性克隆率13.76%),利用PRIMER3PLUS在线软件设计引物163对,采用in silico方法,对微卫星序列进行BLASTN和BLASTX在线搜索。运用BLASTN搜索,首先将设计引物后的微卫星序列(侧翼序列长度大于50bp)与GEN-BANK中的斑马鱼的EST数据库进行比对,共匹配上44个同源序列。然后利用BLASTX搜索非冗余蛋白数据库,有31个微卫星位点成功的进行了功能注释,5个微卫星位点匹配上假设蛋白。本文利用模式生物斑马鱼的基因组资源对银鲫的的基因组进行比较研究,为以后银鲫种质资源的开发打下了良好的基础。     

鲢InDel-RFLP标记开发及其在连锁图谱构建中的应用

基于随机测序的鲢(Hypophthbalmichthys molitrix)基因组片段,尝试开发基于InDel的限制性片段长度多态性标记(InDel-RFLP).结果显示:共133个片段中,65个在一个野生鲢群体(该野生鲢群体采自长江流域荆州段,31个个体)中表现多态性.共检测到163个等位基因,每位点等位基因数从2到...     

1株鲢病原弧菌的分离鉴定

从养殖的患病鲢(Hypophthalmichthys molitrix)组织分离出1株病原菌CQWL002,革兰氏阴性,短杆状,菌落半透明。经回归感染试验,证明该菌为鲢的病原菌。用API系统结合常规生理生化实验对该菌进行初步鉴定。为了进一步确定该菌的分类学地位,测定了其16SrDNA序列,分析了相关细菌的同源性,构建其系统发育树。结果表明,该菌株与河流弧菌(Vibrio fluvialis)的亲缘关系最近。综合上述几种方法的鉴定结果,最后鉴定株菌CQWL002为河流弧菌。