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1.
大黄鱼是多年生高价值的经济鱼类,其养殖周期至少要18个月,故大黄鱼人工养殖必须经过一个漫长的冬季。尽管福建以南的海域大黄鱼养殖能安全越冬,但由于大黄鱼属深层鱼类,所以在我国浙江以北的大部分海域大黄鱼人工养殖越冬还是成为广大养殖业者所担心的主要问题和所要解决的主要技术问题之一。为此,1997年我们进行了大黄鱼的越冬试验,试验的主要目的是要搞清楚大黄鱼的停食温度,极限致死温度和进食温度等。一、材料与方法1、鱼种来源大黄鱼鱼种来源于我公司放养的规格为2.scm/尾的鱼苗,经过6个多月的养殖,体长达到16一18cm/尾,…  相似文献   

2.
通过硫酸铵分级沉淀、Sephadex G-50凝胶层析制备大黄鱼幽门腺胰蛋白酶,并对其特性进行了研究。大黄鱼胰蛋白酶的最佳催化pH是8.0,在反应时间段内活性最高的温度为55℃。随着温度升高,大黄鱼胰蛋白酶稳定性显著下降。在55℃时的催化活性很高,但稳定性很差,15 min后酶即失活84.4%,1 h后活力下降则达95.6%。  相似文献   

3.
为优化大黄鱼(Larimichthys crocea)活体运输的条件,对大黄鱼的生态冰温进行探索。分析鱼水质量比和暂养时间2个因素对大黄鱼保活时间的影响,在此基础上设计3因素3水平的正交试验,以期找到大黄鱼保活的适合条件。研究结果显示:大黄鱼的生态冰温为-2℃~7℃;鱼水质量比及暂养时间对大黄鱼保活时间均有显著影响(P<0.05);在温度为5℃~7℃、鱼水质量比为1∶4、暂养时间为48 h的条件下进行保活,保活时间可超过19 h。本研究结果可为大黄鱼活体运输提供参考。  相似文献   

4.
大黄鱼 ,俗称黄鱼、黄瓜鱼、黄花鱼 ,是我国主要的海洋经济鱼类之一。大黄鱼是暖水性集群洄游鱼类 ,对温度的适应范围为 8~ 32℃ ,最适生长温度为 1 8~ 2 5℃ ,水温底于 1 4℃和高于 30℃摄食明显减少。通常栖息于水深 60m以内的近海中下层 ,厌强光 ,喜浊流 ,黎明、黄昏或大潮时多上浮 ,白昼或小潮多下沉。大黄鱼为广食性鱼类 ,自然环境中食饵多达上百种 ,成鱼食各种小型鱼类 ,幼鱼食桡足类、糠虾、磷虾等浮游动物。大陈岛深水网箱养殖大黄鱼始于 2 0 0 1年初 ,是全国深水网箱养殖大黄鱼最早的地区之一。在两年多的时间里 ,经过反复摸索和…  相似文献   

5.
为探索冷冻大黄鱼通电加热解冻的可行性,采用直接通电和浸泡通电两种方法对大黄鱼进行解冻,分别以空气解冻和流水解冻作为对照组,实时测定大黄鱼各部位的温度,综合解冻时间和均匀性作为解冻效果的评价指标。结果显示,直接通电加热可以有效缩短解冻时间,但解冻均匀性差,鱼体最高温差达30.2℃,不适合大黄鱼的解冻;与对照组相比,浸泡通电解冻速度提升近1倍,且均匀性较好,适合大黄鱼的解冻。为了掌握浸泡通电解冻工艺参数,研究了电源形式、电压、导电液浓度对解冻效果的影响。研究表明,电源形式(直流或交流)对解冻无显著影响,220 V最适合大黄鱼的解冻,导电液浓度为1%时解冻效果最好;重量为500 g左右的冷冻大黄鱼通电加热解冻工艺为:1%Na Cl浸泡,220 V交流电通电18 min,解冻终温为5.2℃。  相似文献   

6.
为研究温度对离体大黄鱼头肾巨噬细胞抗氧化能力和炎性反应的影响,从大黄鱼头肾组织中分离巨噬细胞结合贴壁筛选法得到细胞单层后,在不同温度(16、22和28°C)下培养备用。使用25μg/mL的脂多糖(LPS)孵育细胞2 h后,测定不同培养温度下离体细胞活力、呼吸爆发活性、抗氧化酶(SOD和CAT)活性以及相关基因(SOD、CAT、Hsp70和IL-1β)表达的情况。结果显示,体外培养细胞36 h后,16°C和22°C条件下培养的细胞活力显著高于28°C处理组;LPS处理组大黄鱼头肾巨噬细胞呼吸爆发活性显著升高,但SOD和CAT酶活性较对照组显著下降。高温(28°C)显著提高了细胞CAT酶的活性和基因表达水平,但SOD酶活性和基因表达变化差异不显著;LPS显著促进了大黄鱼头肾巨噬细胞IL-1β基因的表达,并且随培养温度升高细胞IL-1β基因的表达水平显著降低;但大黄鱼头肾巨噬细胞Nrf2和Hsp70的基因表达量随温度升高而显著增加,且LPS处理组细胞基因表达水平显著高于对照组。研究表明,温度显著影响了离体大黄鱼头肾巨噬细胞的抗氧化能力和LPS所诱导的促炎基因的表达,Nrf2和Hsp70在这一过程中可能发挥重要作用。  相似文献   

7.
刘瑞炜  任全娜 《齐鲁渔业》2002,19(10):12-12
大黄鱼为我国特有的地方性珍贵鱼类,在我国近海,北起黄海南部,经东海台湾海峡,南到南海雷洲半岛以东均有分布,比较明显的产卵场和渔场就有10个之多。大黄鱼是温暖性集群洄游鱼类,对温度的适应范围是10~32℃,最适生长温度为18~25℃;适盐范围为24.8~34.5,最适盐度为30.5;pH为7.85~8.35;一般DO在4 mg/L以上,最低不能低于2mg/L。由于近几年资源衰退,枯渔滥捕,大黄鱼产量远远满足不了人们生活的需要。为此,我们在胶洲湾海域进行了大黄鱼网箱养殖试验,取得较好效益,现将养殖技术介绍如下:  相似文献   

8.
为探究大黄鱼肌原纤维结合型丝氨酸蛋白酶(MBSP)的性质,实验采用生物信息学方法对大黄鱼MBSP进行基因检索与筛选,通过分子克隆得到大黄鱼MBSP编码区全长cDNA并构建毕赤酵母表达系统得到重组蛋白质(Lc-rMBSP),分析Lc-rMBSP的酶学性质和二级结构并通过同源建模分析Lc-MBSP的三级结构。结果显示,大黄鱼肌原纤维蛋白中存在MBSP,在55°C下活性最高。大黄鱼基因组中注释为类胰蛋白酶的基因有16条,对这些基因与淡水鱼MBSP进行系统进化树分析和多序列比对,得到同源性较高的基因序列(Lc-MBSP)。Lc-MBSP编码区全长735 bp,共编码244个氨基酸残基。通过毕赤酵母重组表达,分离纯化得到分子量约28 ku的重组蛋白质Lc-rMBSP。表达蛋白的最适温度和pH分别为50°C和8.0。圆二色谱分析表明,温度对Lc-rMBSP二级结构具有较大的影响。Lc-rMBSP在较宽的温度范围内(40~60°C)对MHC具有较高的水解活性。Lc-rMBSP的最适底物为Boc-Leu-Lys-Arg-MCA,并且特异性切割羧基侧的精氨酸残基,而不分解赖氨酸残基。通过同源建模得到Lc...  相似文献   

9.
田玉先  冯德军  张华  桂福坤  曲晓玉 《水产学报》2022,46(11):2084-2096
为了明确大黄鱼在大型围网养殖区内的分布规律,实验通过集成、构建具备大黄鱼探测以及水温、盐度、光照、pH、溶解氧等海洋环境探测功能的小型探鱼无人船,并在浙江省舟山市桃花岛大黄鱼围网养殖基地内开展了6次现场监测。结果发现,(1)在水平范围,大黄鱼主要分布在大型围网养殖区内礁石丰富且水流相对较缓的区域;(2)在垂直范围,大黄鱼主要分布在加权相对深度0.6~0.9的养殖海区中下层;(3)围网养殖海区内温度、盐度、pH、溶解氧等海洋环境条件整体变化较小,大黄鱼往往分布在光照强度分别为(5 921±2 702)、(50 799±50 988)、(5 990±542)、(3 494±695)、(6 836±4 761)及(15 395±5 531)lx等相对较弱的区域。本实验首次通过小型探鱼无人船系统研究了围网养殖区内大黄鱼的分布特性及相应的海洋环境因子对其分布的影响,结果为大黄鱼围网养殖区的操作平台选址、投喂管理、起网设计等提供了依据。  相似文献   

10.
突变高温胁迫对大黄鱼血清生理指标的影响   总被引:6,自引:0,他引:6  
鱼类作为变温动物,在水温突变时体内会发生一系列生理变化。本研究分析了突变高温胁迫下大黄鱼幼鱼血清皮质醇(COR)、血糖(GLU)以及乳酸(BLA)含量的变化规律。实验选取8月龄平均体重为(118.8±6.05)g的大黄鱼作为实验对象,对照组设定温度为(23±0.3)℃,实验组设定温度为(33℃±0.3)℃,变温过程为突变,观察记录实验现象。结果表明:大黄鱼幼鱼在33℃高温胁迫下有强烈的应激反应,表现为呼吸加快、极度不安、游动剧烈。经33℃高温胁迫2 h后,实验组幼鱼血清中皮质醇、血糖、乳酸含量与对照组相比均有显著的升高(P0.05或0.01),陆续出现死亡,最终全部死亡。研究认为,33℃高温胁迫对大黄鱼有致命的影响,在养殖生产过程中要将水温严格控制在33℃以下。  相似文献   

11.
For body weight (BW) and morphological traits measured repeatedly during growth in Japanese flounder, random regression models (RRMs) were constructed to genetically analyse growth curves and relative growth of morphological traits to BW or body length (BL). In the RRM of growth curves, genetic effects were optimally modelled using Legendre polynomials of two orders for six growth traits. Family and permanent environmental effects remained constant for morphological traits, whereas family effects changed linearly for BWs. During the measuring periods, the heritabilities of the traits increased with age and ranged from 0.256 to 0.843 for BW, 0.379 to 0.806 for body height, 0.338 to 0.773 for BL, 0.286 to 0.665 for head length, 0.159 to 0.708 for length of caudal fin and 0.335 to 0.774 for width of caudal peduncle. Genetic correlations for each trait decreased with increased lag in days of age. In the RRM of relative growth, all morphological traits analysed were significantly associated with BW and BL. The heritabilities for the allometries of morphological traits to BWs ranged from 0.251 to 0.755, whereas those to BLs ranged from 0.412 to 0.871. The majority of genetic correlations among these allometry scalings were negative. These estimated parameters can be utilized to not only guide the efficient selection of traits, but also to genetically regulate synchronous growth of body shape with BW in Japanese flounder.  相似文献   

12.
ABSTRACT

This study used a choice experiment to analyze the preferences of consumers for the attributes of tilapia (price, mode of production, product form, and size), a major aquaculture product in Tanzania. The results showed that consumers were willing to pay a price 665.020 Tanzanian shillings (TZS) lower for farmed tilapia than for wild tilapia; a price TZS 833.210 and TZS 1799.110 higher for medium-size and large-size tilapia respectively than for small-size tilapia; and a price TZS 1214.090 higher for fresh tilapia than for smoked tilapia. Consumers’ willingness to pay less for farmed tilapia than for wild tilapia is mainly attributed to issues related to taste and availability. It was also found that consumers were heterogeneous in their preferences for all the tilapia attributes (mode of production, size, and form) considered in this study.  相似文献   

13.
王志平 《河北渔业》2011,(3):45-47,50
水产养殖专业英语是为了适应社会经济发展而为学生开设的一门考查课,其目的是让学生掌握一种获取更多资料和信息的语言工具.然而,我国至今没有一本适合普通高职院校学生的专业英语教材.根据自身教学实践,本文从教学内容选择及教学手段改革两方面进行了细致深入的阐述,希望对我国水产养殖专业英语或其他学科专业英语的课程教学改革有所启发.  相似文献   

14.
To determine the intensity of helminth infection and egg output with regard to age and sex of wild boar, stomachs and intestines of 124, lungs of 62, and livers of 39 animals from 5 enclosures in Southern Germany were examined. The evaluation of the intensity of infection showed 579.4 worms per animal for Hyostrongylus rubidus, 510.4 for Globocephalus longemucronatus, 476.9 for Oesophagostomum dentatum, 476.9 for O. quadrispinulatum, 254.2 for Metastrongylus pudendotectus, 176.9 for M. salmi, 140 for Physocephalus sexalatus, 56.9 for M. apri, 45.4 for Trichuris suis, and 3.3 for Ascaris suum. 33.6 liver flukes per infected wild boar were also found. Additionally 2 metacestodes of Taenia hydatigena on the serous liver coat of an adult sow were found. The worm burden with respect to age of the animals showed no or only minimal age related differences, whereas a large number of O. dentatum and O. quadrispinulatum was found in adults compared to younger wild boars. The evaluation of the intensity of infection with regard to sex of the animals showed higher values only for H. rubidus, O. dentatum, O. quadrispinulatum and P. sexalatus in males compared to female wild boars. The egg output intensity in the samples taken from the rectum was in average 3300 EpG for A. suum, 450.4 EpG for Oesophagostomum, 445.9 EpG for Globocephalus, 220 EpG for Trichuris, 207.9 EpG for Metastrongylus, 190.8 EpG for Hyostrongylus and 67 EpG for Capillaris. The egg output with respect to age showed higher values in younger wild boars than in adults.  相似文献   

15.
Aquaculture, for better or worse, depends in part on drugs for the prevention, control and eradication of a variety of diseases. The US Food and Drug Administration's Centre for Veterinary Medicine, through the Federal Food, Drug and Cosmetic Act, strictly controls the approval and use of drugs in animals, including aquatic animals. Laws and regulations exist that regulate the investigational use and approval of new animal drugs for all animals. However, in reality, these mandates must be uniquely interpreted for aquatic species. Very few drugs are approved for use in aquatic species. There is a growing effort by non-traditional sponsors (aquaculturists as opposed to pharmaceutical firms) to gain approvals for several new animal drugs. Simultaneously, the federal government, including the Centre for Veterinary Medicine, is working aggressively with the private and public aquaculture sectors to facilitate submission and subsequent approval of new animal drug applications. The drug approval procedures and requirements for aquatic animals are discussed. Special attention is given to their similarities and differences, relative to traditional terrestrial animals.  相似文献   

16.
《水生生物资源》1998,11(4):211-217
The general principles behind the bioenergetic approach for predicting growth, as well as for decreasing feed and nutrient losses, have been set forth for salmonids. Given the diversification of fish fanning activities around the world and the ever increasing concern for water quality management, it becomes essential to verify whether an approach developed for salmonids is applicable to other species. Given this general background, an attempt is made here to check the theoretical assumptions and technical considerations behind the bioenergetic principles developed for rainbow trout with other freshwater or marine species. From a conceptual point of view, recent literature data do indicate that as far as nitrogen or energy balance is concerned, the general scheme is as valid for marine species as it is for salmonids, even in quantitative terms. Given the methodological tools available today, it should not be difficult to reduce feed and nutrient losses and to estimate the potential environmental loadings using the same principles for non-salmonids.  相似文献   

17.
Pond experiments with one treatment per pond are discussed for their sources of variability. Replication of treated ponds, randomization of treatment allocation to ponds and the importance of independence between ponds are emphasized for efficient estimation of both treatment and inherent pond differences. Appropriate models are given for the analysis of data for pond experiments with whole-pond treatments. Corresponding analyses of variance are given to illustrate the estimation of differences between treatments, between ponds and between fish within ponds. Appropriate significance tests for treatment effects are demonstrated to avoid pseudoreplication, the incorrect use of within-pond variation. Using a fertilizer experiment, simple graphical methods are presented for examining between- and within-pond variation to identify ponds with unusual data, and to determine adequacy of design and appropriate analyses.  相似文献   

18.
Three lakes were repeatedly sampled at night using boat electric fishing, experimental gill netting, and fyke netting from May to November 1993 to evaluate the feasibility of using proportional stock density (PSD) to monitor warm-water fish populations in Washington State, USA. Additionally, average night-time boat electric fishing catch-per-effort of largemouth bass, Micropterus salmoides (Lacepéde), from 30 Washington lakes was also analysed to determine the amount of effort required to obtain adequate samples for precise PSD estimates. Temporal variations in PSD were not large enough to affect the management of warm-water fish populations in the small Washington lakes studied. However, the considerable effort required to obtain precise PSD estimates may limit its usefulness for warm-water fisheries surveys in the Pacific Northwest. On average, from three to 13 nights of electric fishing effort are needed to capture enough stock-length largemouth bass for PSD estimates, depending on the precision desired (80–95%) and the location of the lake (eastern or western Washington). Catch of stock-length fish can be maximized by using electric fishing for centrarchids and gill netting for yellow perch, Perca flavescens (Mitchill), in June or September. Adequate samples for precise PSD estimates can be difficult to obtain from Pacific Northwestern lakes, even when using recommended gear at optimum sampling times. Inability to capture an adequate sample size for precise PSD estimates may be responsible for some of the fluctuation in PSDs in some studies of warm-water fish populations in northern areas. Managers in other northern climates may find that low sample size may account for large variations in PSDs reported.  相似文献   

19.
根据厄尔尼诺年春季(2016年3—5月)我国灯光罩网渔船在中国南海中沙群岛海域生产调查期间采集的572尾鸢乌贼样本,对其渔业生物学特性进行了研究,初步探讨了厄尔尼诺现象对鸢乌贼渔业生物学特性的影响。结果显示,厄尔尼诺年间雌性鸢乌贼胴长范围为59.5~207.5 mm,优势胴长组为90~150 mm,占样本总数的66.24%;雄性胴长范围为56.5~236.5 mm,优势胴长组为60~120 mm,占样本总数的78.81%,雌雄样本优势胴长存在显著性差异。雌性样本体质量范围为7~318 g,优势体质量组为20~140 g,占样本总数的70.18%;雄性体质量范围为7~381 g,优势体质量组为0~80 g,占样本总数的92.14%。雌性鸢乌贼净重比例范围为46.59%~86.67%,平均为70.19%;雄性为42.86%~91.11%,平均为73.12%。不同性别间鸢乌贼胴长与体质量、胴长与净重的生长关系存在显著性差异:雌性胴长与体质量、净重的生长均最适合用幂函数表示,而雄性则均适合用指数函数表示。全部鸢乌贼样本的性别比例为41.43∶58.57,雄性样本多于雌性样本;雌雄样本的性成熟度主要以Ⅰ期和Ⅱ期为主,分别占样本总数的61.7%和85.79%。样本胃饱满度以0~2级为主,胃含物主要包括头足类、中上层鱼类、软体动物以及甲壳动物等。厄尔尼诺年间中沙群岛海域的平均表温较上一年度偏低0.213°C,可能会对该海域鸢乌贼的渔业生物学特性产生影响,使其个体变小。  相似文献   

20.
Accurate digestibility coefficients for protein, energy, and lipid are needed by feed formulators to optimize diets to meet nutritional requirements and to substitute ingredients cost‐effectively. Of particular interest is protein, which accounts for the majority of shrimp feed content and expense. The current study evaluated seven cottonseed meal and protein products. Most of the samples were derived from a glandless cotton variety that lacks significant levels of the antinutritive compound, gossypol. The various protein fractions were evaluated for apparent crude protein, crude lipid, and energy digestibility when fed to juvenile Pacific White Shrimp, Litopenaeus vannamei. Apparent energy digestibility for the protein fractions derived from the glandless seed ranged from 76.7% for ground kernels to 94.6% for protein isolate, and these values were greater than the value obtained for the commercial meal that contained gossypol (64%). Apparent protein digestibility for the six glandless‐cotton‐based samples varied from 72.3% for the ground full‐fat kernels to 94.1% for the protein isolate, and these values were mostly higher than the value obtained for the commercial meal (82.3%). The high apparent digestibility values demonstrate that low‐gossypol cottonseed protein products may be useful as a cost‐effective replacement for more expensive protein sources in L. vannamei diets.  相似文献   

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