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1.
我国渔用疫苗的研制   总被引:3,自引:0,他引:3  
杨先乐 《水产学报》2006,30(3):416-420
定量(quantitive PCR)是用PCR技术评估样本中靶基因的分子数,实现对核酸信息的量化分析及比较。目前主要有外标法和内标法两大类。其中,其中外标法中主要有PCR产物的直接定量法,极限稀释法等;内参标法中主要有竞争性和非竞争性PCR等。  相似文献   

2.
被动集成应答器(passive integrated transponder,PIT)标记是一种基于无线射频识别的标记,以标记的方式来识别目标生物体,主要应用于水生动物的行为、生存生长、分布、监测保护和渔业增殖放流效果评估等研究中。与其它标记技术相比,PIT标记具有信息储存量大、体积小、持久性强、识别度高、唯一性和性能稳定、频率足够低时易于识别及对生物体的生存、生长和游泳能力无显著影响等优点。但也存在不足之处,如有些种类肌肉植入时保留率低;手术伤口溃烂导致生物体死亡;标记迁移影响天线的检测等。PIT标记技术对于水生动物研究具有重要意义,并具有良好的发展趋势。主要综述了基于PIT标记在水生动物、尤其是鱼类的研究中的应用进展,以期为渔业增殖放流效果评估研究和管理工作提供参考。可以预期,PIT标记技术与物理、化学和分子标记等相结合将成为水生动物研究的一个发展趋势。  相似文献   

3.
由于传统海水鱼类的价格不断上升、渔业资源的受损及波动致使人们致力于寻找新的鱼类蛋白源。具有发展前途的是水产养殖业。虽然水产养殖业的产量已有增加,但还具有很大的潜力。许多热带淡水鱼类的商业价值并不高,但却可作为人类食用的潜在的鱼类蛋白源。罗非鱼就是其中的一种,该鱼资源丰富,个体小,市场价格也较低,只有超过400克的鱼体的价格才较高。罗非鱼系多骨鱼类,成熟早,繁殖多,但个体小,不受消费者的重视,  相似文献   

4.
草鱼是我国的四大家鱼之一,具有肉质好。生长快,产量高,饲料来源广,成本较低等优点。也是群众喜食,市场需要,经济效益和社会效益较高的优质鱼类。在生产上草鱼与鲤鱼相比,草鱼吃青饲料,属节粮型鱼类;鲤鱼吃精饲料,属吃粮型鱼类。因为节粮型鱼类可以大量节约精饲料.比吃粮型鱼类生产成本低,经济效益高。因此,草鱼应是当前主要的发展鱼类之一。  相似文献   

5.
鱼类葡萄糖耐量研究进展   总被引:3,自引:0,他引:3  
<正>糖类又称碳水化合物,是自然界存在最多、分布最广的一类重要的有机化合物[1]。陆生哺乳动物通常是以糖类作为主要能量来源,对糖的利用能力较高;但鱼类主要以蛋白质和脂肪作为主要能量来源,对糖的利用能力较低,是先天性的"糖尿病患者"[2]。适宜的饲料糖水平可以起到减少蛋白质供能、提高蛋白质沉积、促进鱼类生长及节约饲料成本的作用[3]。如果饲料中糖类水平超过一定限度,鱼类生长缓慢、抗病力低、死亡率高[4]。糖耐量最  相似文献   

6.
2010年至2012年对长江南京段的渔业资源进行了调查,分析了鱼类资源和饵料生物的状况.共监测到鱼类43种,优势种组成稍有变动,鲫、鲤等经济鱼类的数量与生物量有所增长,在渔获物中的优势地位明显提高.鱼类群落中物种间个体均匀分布的程度无显著变化,群落多样性稍有增长,丰富度指数略提高.浮游生物资源总体保持稳定,但底栖动物的生物量、密度均较低.  相似文献   

7.
<正> 在高密度养鱼中,用生物饵料喂养一些鱼类仔鱼仍是较为有效的途径之一。但培养一般生物饵料较困难,且成本较高。纤毛虫可作大多数鱼类仔鱼的开食饵料,培养方法简单、生长较快、成本较低、可以大量培养。1982—1983年我们用米糠浆作培养基培养纤毛虫喂养草鱼、鲤鱼、金鱼和尼罗罗非鱼仔鱼,效果较好,现将结果作一报道。  相似文献   

8.
秋季黄海底层鱼类群落结构的变化   总被引:15,自引:7,他引:15       下载免费PDF全文
根据1985年和2000年秋季渔业生物资源底拖网调查资料,分析了黄海底层鱼类群落结构的时空变化。结果表明,渔业资源优势种的组成随区域和时间不同有着较大的差异。黄海北部和中部渔获种类组成相似性较高,北部与南部、中部与南部的相似性较低;黄海渔获生物种类组成年间相似性较高,为65。进一步的单因子ANOSIM分析表明黄海底层鱼类群落不同区域和年间种类组成没有显著性差异。黄海渔业生物多样性由北向南递减。与1985年相比,2000年鱼类群落长度谱表现出小型种类和小个体增多,大个体减少,且长度范围变小;主要优势种的长度组成也呈现小型化趋势。长度谱区域变化则是从北部向南部小个体数量增多,大个体数量减少。  相似文献   

9.
我国的主要养殖鱼类以经济价值较低的鲤科鱼类为主,而欧美等发达国家以营养价值较高的鲶形目鱼类为主要养殖对象.如:斑点叉尾鮰、云斑鮰等.近几年,我国虽然在鲶鱼养殖方面开发一些新品种,如:革胡子鲶、金氏鲶等.但因这些品种抗寒性较差,很难在北方地区养殖.松花江水系怀头鲶由于其营养丰富、肉质细嫩、生长速度快、适温范围广、抗病力强等特点,受到养殖者青睐.个体之间互相残杀是制约鲶形目鱼类养殖发展的主要因素.根据其生物学特点,2005年我们开展了套养实验.具体如下,供参考.  相似文献   

10.
钱塘江富阳段鱼类资源现状   总被引:3,自引:0,他引:3  
2014年11月—2015年12月对钱塘江富阳江段3个断面鱼类资源进行了逐月采样调查,对该水域鱼类种类组成、优势种、群落多样性指数和捕捞量进行分析。结果显示:共采集鱼类48种,隶属8目13科37属,其中鲤科鱼类种类最多,占总种类数的64.58%,优势种为鲢、鲤、鲫和光泽黄颡鱼。各月中,4月份捕获的鱼类种数最多,占总种数的52.08%;9月份鱼类捕获量最高,占总渔获量的17.85%。Margalef丰富度指数4月份较高,2月份较低;Shannon-Wiener多样性指数和Pielou均匀度指数在7月份较高,9月份较低,而Simpson多样性指数与之相反。富阳段鱼类捕捞强度较大,渔获物中小个体鱼类占主要部分。与历史记录比较,富阳江段鱼类群落组成已经发生了显著变化,除本地种光泽黄颡鱼外,增殖放流鱼种已成为了优势或重要种群。  相似文献   

11.
An important requirement of many breeding programmes for aquaculture species is the ability to identify organisms individually or at least by family. While a variety of external and internal tagging methods have been developed that can provide efficient identifications systems, most have specific drawbacks. The present study assessed the efficiency of an internal tagging method that can be applied to family selection programmes in crustacean species. Experiments were conducted to test the efficacy of applying visible implant elastomer (VIE) tags to juvenile giant freshwater prawn (GFP). The first experiment assessed performance of VIE tags in juvenile GFP of different size classes and stability of tags placed in different positions in the abdomen with different numbers of tags implanted. The second experiment applied VIE tags in a long term, large scale, field‐based farming experiment. The third experiment tested the reliability of the system. Results showed that juvenile GFP at 2 g were of suitable size for VIE tags with no negative effects evidence on growth and survival. Tag retention rates were above 97.8% in all experiments and tag readability rates were 100% with a correct assignment rate of 95% through to mature animal size of up to 170 g.  相似文献   

12.
Populations of sea cucumbers, including the Japanese common sea cucumber Apostichopus japonicus, have been seriously depleted worldwide due to overfishing. Mark–recapture study is an efficient means of collecting ecological data. However, the use of such a method in sea cucumbers is difficult because they lack hard tissues in the body wall. Here we tested the viability of various tagging methods on A. japonicus. First, we applied conventional tags using four different methods [single spaghetti (T-bar) tagging, double spaghetti tagging, ribbon tagging, and Atkins tagging] to ten individuals per method in aquaria for 14 days. Of the methods used, single spaghetti tagging had the highest retention rate. Then we examined the retention rate of single spaghetti tags on ten individual sea cucumbers for up to approximately 6 months in rearing conditions. The single spaghetti tagging method showed a retention rate of 100% over at least 7 days, and 50% of the tags remained embedded after 56 days. The longest duration of tag retention was 174 days, at which time the experiment was terminated. These results indicate that single spaghetti tagging is reliable for both short- and longer-term studies, making it a useful tool for ecological and conservation studies in sea cucumbers.  相似文献   

13.
Two different colours (red and green) of visible implant elastomer (VIE) were used in Nile tilapia (Oreochromis niloticus). The visibility, location and retention of the VIE tags was investigated and any adverse effects on fish survival and growth determined. The use of VIE tags for monitoring individual fish during a bacterial challenge with either Streptococcus agalactiae or S. iniae was also studied. The results showed that VIE treated fish were lighter but not shorter than the non‐tagged control fish and that tagging caused no mortality. The retention of tags was better at the base of pectoral fin followed by the nasal area, lower abdomen, upper abdomen and branchiostegal rays inside the operculum. During the bacterial challenge experiment individual animals could be easily identified using the VIE tags. In this preliminary study, VIE tagging appears suitable for Nile tilapia research, as with other fish species, and could be a novel method to identify individual animals during microbial pathogenesis studies.  相似文献   

14.
This paper describes the successful use of two tagging systems, both produced by Northwest Marine Technology Inc., on larval and postlarval giant freshwater prawns, Macrobrachium rosenbergii. Visible implant (VI) elastomer tags (a coloured liquid that solidifies under the epidermis) were used on stage XI larval prawns (mean weight 0.01 g) and postlarval prawns (mean weight 0.07 g). VI alphanumeric tags (small biocompatible plastic labels also inserted under the epidermis) were tested on postlarval prawns (from a weight of 0.5 g). Tags were inserted using clove oil as anaesthetic, and survival, mortality and growth rates of tagged animals were compared with those of controls that were handled but not anaesthetized or marked. Twenty per cent of the larval prawns (the smallest of the group) died just after tagging, but thereafter the remaining prawns survived well, as did all the tagged postlarval prawns. Visibility of the VI elastomer tags in larval prawns deteriorated with time, though 79% of marks were still visible to the naked eye 70 days after tagging. VI elastomer tags in the postlarval group remained clearly visible for up to 100 days. Visibility of the VI alphanumeric tags fell shortly after tagging, but remained adequate thereafter. Moult rates in control and tagged animals were the same in larvae with VI elastomer tags and postlarvae with VI alphanumeric tags, but the moult rate in the postlarval prawns given elastomer tags was slower than in controls. Rates of growth were similar in tagged (elastomer and alphanumeric) and control postlarval prawns, once the size‐dependent mortality of tagged larval prawns was taken into account. We conclude that VI elastomer tags could be used to mark small numbers of individual larval and immediately postlarval prawns for periods of several months, and that VI alphanumeric tags could be used to mark an unlimited number of individuals from a size of approximately 0.5 g.  相似文献   

15.
Abstract. The adaptation of proprietary fish-tagging equipment for tagging small lobsters, Homarus gammarus (L.) (9–15mm carapace length), with internal microware tags is described. Tag retention was 85–100% as the animals grew through up to 22–29 moults (90–102mm carapace length) in captivity. Claw loss during handling was reduced from 4% lo less than 1% at a tagging rate of 240 lobsters per has experience was gained.  相似文献   

16.
The utility of visible implant (VI) tags for marking tropical river fish   总被引:2,自引:0,他引:2  
In tropical fisheries where ageing fish is often difficult, tagging programmes offer an important means to estimate growth parameters and mortality rates. The majority of tags are large and attached externally via a puncture in the muscle. These characteristics may cause significant biological effects which bias parameter estimates. Visible implant (VI) tags offer a more benign means to individually mark fish. The utility of VI tags for marking five species of tropical river fish was examined. The results indicate that the tag and tagging operation had no influence on either growth or mortality, although tag retention was poor compared with other studies. For three of the five species, the only suitable tagging location was highly inconspicuous and therefore inappropriate for tagging programmes that rely upon fishermen to return tagged fish. Alternative tagging locations may improve retention rates and the visibility of the tag.  相似文献   

17.
Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often‐untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show ‘normal’ behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye (Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short‐term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post‐tagging effects on behaviour as part of their experimental objectives.  相似文献   

18.
The spawning migration travel times of chum salmon, Oncorhynchus keta (Walbaum), fitted with gastrically implanted radio tags vs external spaghetti tags were tested for a short [≈60 river km (rkm)] and long migration route (≈730 rkm) on the Koyukuk River, Alaska, USA. Using a novel application of statistical arrival curve models to infer travel times for uncaptured fish, migrations by chum salmon not directly handled during the study were also assessed. Results demonstrated negligible differences in travel times within migration routes between fish fitted only with spaghetti tags and fish fitted with radio tags, indicating low impacts on migration travel behaviour associated with gastric tags once deployed. Conversely, travel times for unhandled fish as inferred by statistical arrival models may have been 12%–24% shorter than those for fish captured with gillnets for tagging. These results suggest that, if present, chum salmon migration behaviour impacts may be more strongly associated with fish capture than tag deployment.  相似文献   

19.
Abstract  A hatchery experiment was organised to find out if the high loss rate of coded wire tags, noticed in connection with an Arctic charr Salvelinus alpinus (L.) restocking programme, was size-dependent and also to test head moulds for future taggings. Six moulds made by Northwest Marine Technology Inc. and five moulds made at the Finnish Game and Fisheries Research Institute were used. A total of 100 charr were tagged with standard-length coded wire tags using each mould. One-summer old charr at tagging were held for 534 days and two-summer old charr for 320 days. The tag loss rate varied between 0% and 54% and was negatively related to the size of the charr at tagging. The high loss rate was connected with the poor alignment of some moulds, such that a large proportion of the tags were located in the nasal cavity instead of the nasal cartilage. Testing of the moulds and careful grading of the fish for tagging is emphasised, especially if Arctic charr smaller than 20 g in weight are to be tagged.  相似文献   

20.
Octopus vulgaris is a species of demand in the market with the potential to diversify European aquaculture. However, this species develops complex social interactions under culture conditions, which may have negative effects on its growth, survival and profitability. In order to understand its behaviour under such conditions, individual tagging systems allow a careful evaluation of biological parameters, such as growth and longevity. The present work describes a combined protocol (anaesthetic and tagging) for implanting subcutaneous passive integrated transponder tags (PIT). The effect of two anaesthetic agents in facilitating octopus handling is assessed: clove oil at 20–40–100 mg L?1 and ethanol (96%) at 1–1.5–2%. The most suitable body location of PIT tags, its effect on growth and mortality, the addition of a stitch and the PIT retention rate after 2 months in floating cages were evaluated. It was concluded that immersion in seawater with 1.5% of ethanol at 22.3±0.5 °C is a suitable anaesthetic for this species. The results showed that the best‐selected PIT body location was the upper left arm III. No effect of the PIT tagging system was found on growth and survival when tagged and untagged octopuses were compared. It was observed after 2 months that the stitch did not induce an increase in the retention rate and 81–100% tag retention regardless of the dietary treatment.  相似文献   

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