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1.
美国金鳟和日本鳗鲡精浆的化学组成和渗透压   总被引:4,自引:1,他引:3  
本研究采用原子吸收分光光度法(AAS)和气相渗透压仪测定了人工养殖美国金鳟和日本鳗鲡精浆的化学组成和渗透压。研究结果表明,Na+、K+是精浆中的主要离子,可能在维持精浆渗透压和精子活动能力中有重要的作用。人工养殖美国金鳟与日本鳗鲡相比,精浆离子含量各项指标除K含量较高之外(P<0.01),其它各项指标均无显著性差异。本实验的两种鱼与其它种类海淡水鱼类比较,各种离子含量均较高;美国金鳟精浆渗透压值与其它鱼类相似,均保持在300 mOsm/kg的水平。  相似文献
2.
电子标记辅助虹鳟家系建立及快速生长家系筛选   总被引:3,自引:0,他引:3       下载免费PDF全文
以中国水产科学研究院黑龙江水产研究所选育的虹鳟(Oncorhynchus mykiss)优良品系G1世代为基础群体,开展了电子标记辅助的大规模虹鳟家系构建工作,建立了G2世代全同胞家系72组,并初步进行了快速生长家系的筛选工作。对不同家系鱼种进行电子芯片植入后放在同池进行生长比较,本研究中虹鳟上市日龄(约为850日龄)体质量、体长的总体家系效应都达到了极显著水平(P<0.0001);通过对不同家系间850日龄体质量和体长的家系效应显著性检验与最小二乘均值的多重比较分析,获得了682BABB、6717B7A、6828308、682A50A、6829C24、6829DC7、682A382、68284DA这8个体质量和体长性能优良的家系。上述家系将作为优先入选家系进入组建G3世代的储备亲本群体。本研究结果可以与本课题组先期开展的基于个体育种值BLUP分析的多性状复合育种工作相互印证。这将有助于提高对虹鳟生长性状进行遗传选择的准确性,同时对其他水生动物数量性状的遗传选育研究也具有借鉴意义。  相似文献
3.
The effect of solvent‐extracted cottonseed meal (SCSM) as a partial or total replacement of fishmeal was studied in juvenile rainbow trout (Oncorhynchus mykiss). Six experimental diets SCSM0, SCSM25, SCSM50, SCSM75, SCSM75A and SCSMT, containing a gradient of SCSM 0, 152, 305, 465, 460 and 610 g kg−1 to replace 0, 112.5, 225, 337.5, 337.5 and 450 g kg−1 fishmeal protein were fed to triplicate groups (initial body weight of 39.2 ± 0.1 g) for 8 weeks. The diet SCSM75A was supplemented with lysine and methionine, to be similar to SCSM0 for juvenile rainbow trout. Faeces were colleted after 4 weeks of normal feeding for apparent digestibility coefficients (ADC) of dry matter, crude protein and gross energy determination. Total replacement of fishmeal adversely affected growth performance. Fish fed with diet SCSMT had significantly (P < 0.05) lower weight gain, specific growth ratio, feed conversion efficiency (FCE) and protein efficiency ratio than fish fed with other diets. The FCE of SCSM75 and SCSM75A were significantly lower (P < 0.05) than those of fish fed with SCSM0 diets. The ADC of the dry matter of SCSM75 and SCSMT were significantly lower than the SCSM0 diet, and the ADC of crude protein and the energy of SCSMT were the lowest (P < 0.05). The ADC of threonine, proline, alanine, valine, isoleucine, leucine, lysine and methionine of fish fed with diet SCSMT were lower. Lysine and methionine supplement positively affected the ADC of SCS75A diet. There were no significant differences in the fish body composition. It is shown that SCSM can be utilized in the juvenile rainbow trout diet up to 305 g kg−1, to replace about 50% of fishmeal protein in this experiment.  相似文献
4.
The present study aimed to evaluate the importance of “discreet” vertebral abnormalities in normally-shaped rainbow trout in relation to vertebral bone condition in French fish farms. A total of 373 trout (262 ± 2 mm in total length) from 20 fish farms sampled were studied. The fish were radiographed and the axial skeleton examined for vertebral abnormalities. Vertebrae from the middle axial region (V32-38) were selected to evaluate vertebral bone condition. Bone mineralization (BM, %) was estimated by the ratio of ash and dry weight. Bone compactness (BC,%) was measured using Bone Profiler 3.23 images software on digitized radiographs of transverse sections (125 ± 10 μm). Statistical analyses were performed to test the relationships between the occurrence of vertebral abnormalities, and BM and BC. The occurrence of affected trout ranged from 0 to 55% depending on the farm. Trout displayed vertebrae with low BM (< 54.6%) and low BC (< 28.1%) in 40% and 55% of the farm, respectively. No relationships were observed between bone condition parameters (BM, BC) and the occurrence of vertebral abnormalities. These results could be explained by a wide and variable plastic response of bone characters (i.e., vertebral abnormalities, BM and BC) to the various rearing conditions in the fish farms sampled.  相似文献
5.
Abstract– Genetic differentiation between two reproductive ecotypes of anadromous steelhead found in the Middle Fork Eel River in northern California was tested using 16 microsatellite loci. Twelve of these loci showed significant differences in allelic frequency between the two Middle Fork Eel River steelhead populations (Fisher's exact P <0.05). Fisher's combined test for independence also supported significant genetic separation between the two reproductive ecotype ( P < 0.001). Analysis of molecular variance indicated that only 1% of the overall microsatellite allelic variation contributed to differences between summer- and winter-run steelhead in the Middle Fork Eel River. Variation found among individuals within the two runs equaled 18.2%. Analyses showed less genetic distance between the two populations of steelhead in the Middle Fork Eel River than in comparisons made with geographically proximate coastal winter-run fish. Divergence time based on genetic distance for the two within-basin reproductive ecotypes was estimated to be 16,000–28,000 years ago.  相似文献
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8.
Inactivated infectious haematopoietic necrosis virus (IHNV) vaccines   总被引:1,自引:0,他引:1  
The inactivation dynamics of infectious haematopoietic necrosis virus (IHNV) by b-propiolactone (BPL), binary ethylenimine (BEI), formaldehyde or heat and the antigenic and immunogenic properties of the inactivated vaccines were evaluated. Chemical treatment of IHNV with 2.7 mm BPL, 1.5 mm BEI or 50 mm formaldehyde abolished virus infectivity within 48 h whereas heat treatment at 50 or 100 degrees C rendered the virus innocuous within 30 min. The inactivated IHNV vaccines were recognized by rainbow trout, Oncorhynchus mykiss, IHNV-specific antibodies and were differentially recognized by antigenic site I or antigenic site II IHNV glycoprotein-specific neutralizing monoclonal antibodies. The BPL inactivated whole virus vaccine was highly efficacious in vaccinated rainbow trout challenged by waterborne exposure to IHNV 7, 28, 42 or 56 days (15 degrees C) after immunization. The formaldehyde inactivated whole virus vaccine was efficacious 7 or 11 days after vaccination of rainbow trout but performed inconsistently when tested at later time points. The other vaccines tested were not efficacious.  相似文献
9.
一株虹鳟源传染性胰腺坏死病病毒的分离与鉴定   总被引:1,自引:1,他引:0       下载免费PDF全文
熊权鑫  朱玲  汪开毓  杨倩  贺扬  王二龙 《水产学报》2018,42(7):1132-1139
为明确引起四川石棉某养殖场饲养的虹鳟患病死亡的病原体,实验对自然发病虹鳟进行大体病变观察并对其病原体进行分离,通过人工感染实验及多重RT-PCR鉴定确定病原体WZ160509,并对病原体的主要结构蛋白VP2进行扩增分析,同时对病变组织进行组织病理学观察。结果显示,患病鱼主要临床症状表现为体表发黑,腹部膨大,挤压腹部可见肛门喷射淡黄色黏液便;剖检可见肝脏、肾脏苍白;肠道内无食物,内积黄色黏液。将患病虹鳟组织匀浆液无菌接种虹鳟鱼生殖腺细胞系(rainbow trout gonad cell line,RTG-2)细胞,盲传3代均出现典型的细胞病变。人工感染实验显示死亡率高达90%,并出现与自然患病鱼相同的症状。多重RT-PCR检测发现,自然发病鱼、人工感染鱼以及病变RTG-2细胞均为传染性胰腺坏死病病毒(infectious pancreatic necrosis virus,IPNV)阳性,其主要结构蛋白VP2基因与美国分离株基因组1型聚为一支,且同源性分析表明,WZ160509-VP2与IPNV-VP2(AY026345)的同源性最高,序列一致性为95.8%。组织病理学观察显示,患病鱼胰腺细胞空泡变性,坏死;肝细胞空泡变性,坏死;肾小球轻度炎症,毛细血管通透性增加,肾小囊腔内有红色絮状蛋白类物质渗出,肾小管上皮细胞空泡变性。研究表明,从该养殖场患病虹鳟中分离到的病毒为IPNV。  相似文献
10.
嗜水气单胞菌灭活疫苗对虹鳟免疫力和抗病力的影响   总被引:1,自引:0,他引:1  
为研究嗜水气单胞菌(Aeromonas hydrophila)灭活疫苗对虹鳟(Oncorhynchus mykiss)(250 g±12 g)免疫力和抗病力的影响,给试验鱼腹腔注射0.2 mL的灭活嗜水气单胞菌悬液(1.0×108cfu/mL)。分别在注射前(0 d)和注射后7、14、21、28、35、42 d取样,测定血液白细胞吞噬活性、血清溶菌酶(LZM)活力、补体C3含量以及头肾和脾脏中IgM、IgT基因表达情况。结果表明:注射嗜水气单胞菌疫苗能显著提高白细胞吞噬率(PP)和吞噬指数(PI)、LZM活力和补体C3含量,注射后21 d达峰值,PI、LZM和补体C3在42 d仍显著高于对照组。免疫后21 d头肾和脾脏中IgM基因上调表达,35 d达峰值(分别上升24倍和26倍),42 d下降但仍极显著高于对照组。头肾和脾脏中IgT的上调表达比IgM弱得多,头肾35 d达峰值(上升6.2倍),脾脏28 d达峰值(上升6.1倍)。免疫42 d后嗜水气单胞菌攻毒结果表明,嗜水气单胞菌灭活疫苗对虹鳟有较高的免疫保护作用,免疫保护率达到71.43%。  相似文献
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