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1.
IntroductionProductivity of an ecosystem may be measured in terms of structure,abundance and growth of keyspecies.Stock structure,measured as age or size composition in a given stock may indicate whether the stockis in a state of growing,stable or declining.Individual growth may be measured in terms of annual growth ofindividual age groups and maturity of key species will similarly reflect the potential of the species to copewith the influence of a changing environment of predators and human i… 相似文献
2.
Artificial - based fish multiplication and liberation is one of the most efficient ways for sustaining fish population, and is carrying out in the much more hydropower stations in China. In this paper, we took the Gongguoqiao ＆ Miaowei hydropower station as an example, and aimed to briefly introduce the design process of fish hatchery. The key techniques including the multiplication and liberation size, the parent fish amounts, and the all kinds of breed facilities, were discussed, and the expected research direction was put forward. 相似文献
3.
Interleukin-1β(IL-1β) is one of the most pleiotropic cytokines and a central regulator of the immune and inflammatory responses. Interleukin-1β was initially discovered within mice and humans and over the last 10 years has been characterized within a wide variety of animals. The IL-1β plays a key role in the inflammatory process, enhancing cell-mediated immunity by inducing the growth and proliferation of lymphocytes, connective tissue cells, and by stimulating immune and inflammatory response effector cells.As an immunoregulatory cytokine, IL-1β has the potential to enhance the immune response induced by a vaccine and/or to modulate the immune response leading to different effector mechanisms. It is produced by many cell types, including monocytes, macrophages,T and B lymphocytes, fibroblasts, and endothelial and epithelial cells. Expression is induced by a diverse range of stimuli, including mitogens, cytokines, and microbial products. There have been considerable evidences provided by biological cross reaction that fish produce IL-1β during immune responses, and the bioactivity of IL-1 in fish has been known for over a decade. But only. since 1999,IL-1β gene has been cloned from the rainbow trout. And from then on, IL-1β gene has been cloned and expressed in many fish confirming that fish produces IL-1β gene during immune responses. In mammals it is produced as an inactive precursor that is processed by interleukin converting enzyme (ICE) to give a biologically active ‘mature‘ peptide. There is no signal peptide in IL-1β and its mechanism is unknown. This is the special part of the gene structure of the IL-1β. And through the program analyzing, we found this special structure in fish IL-1β gene. This paper reviews the functions and structure of gene IL-1β and the studies of the gene IL-1β in fish recently. 相似文献
4.
半滑舌鳎染色体核型分析 总被引：34，自引：6，他引：28
The tonguefish Cynoglossus semilaevis (Giinther) is a rare fish species in Chinese offing, inhabiting in the warm water bottom. The metaphase chromosome preparation of the fries has been got from their fins by hot air drying methods, while the metaphase chromosomes of one year old young fish which has physiologically sex differentiation has teen got from their renal tissues by the method of PHA and colchicine injection. The karyotypes were examined. The result shows that there are 42 acrocentric chromosomes in diploid and their karyotype formula is 2n = 42t, and there existed heterotypic sex chromosome which belongs to ZW/ZZ type. The sex ratio in artificial bred stock is nearly 1 : 1. 相似文献
5.
动植物蛋白源替代鱼粉研究进展 总被引：42，自引：5，他引：37
With the fast development of aquaculture, fish meal needs increased in recent years, however the quantity of fish catching decreases gradually. Fishmeal is a limited feed resource, and serious concem exists on the future availability of this feedstuff for incorporation in fish diets. Undoubtedly, fish meal is well recognized as the best dietary protein source for most marine carnivorous fishes which required high dietary protein levels compared to omnivorous or herbivorous fish. Fishmeal is known for their high content of essential amino acids and fatty acids, low carbohydrates, high digestibility, low levels of anti-nutritional factors (for fresh fish meal) and is a very good source of minerals and is highly palatable. Thus fish meal is in high demand as the protein source for many formulated diets. However, production of fish meal consumes approximately 35 % of the total global fish catch, and the increasing price and potentially unstable supply in the market could be limiting factors for marine fish culture. There have been strong efforts to define and develop cost-effective protein sources that can, at least partly, substitute for expensive high-quality fish meals in least-cost feed formulations. The search for fish meal substitutes and altemative dietary protein sources is an international research priority that could be of considerable economic advantages. Therefore it is urgent task to find animal and plant protein sources in place of fish meal. Among these, plant feedstuffs have received most attention in recent years, but due to their amino acid unbalances, .presence of anti-nutritional factors and low palatability, a high level of replacement of fish meal with plant feedstuffs in omnivorous fish is generally not well accepted. This paper reviews the research status for other protein sources replacing fish meal based on available information in the literature. Animal and plant protein sources nutrient values are evaluated from the aspect of digestibility, antinutrients, physiological status and suitable supplementation. 相似文献
6.
The fish spawning ground had been investigated on the Beijiang River near Shaoguan city and the influence on fishes breeding from 7 dam had been estimated.Main result are as follows:the four dam building and designed will result in a big destruction.including disrupt the fish migration(Mengli Dam and ChangshanDam),the fish spawning ground disappear(below Zhangtan Dam).a huge destruction in Ankou fish spawning ground by Changan Dam and a serious of damage on grass lying -egg species will caused by Wantou Dam,especially for catifish Mystus suttatus.On the other hand Zhangtan Dam,Kongiiang Dam,and Menzhou Dam obstructed the fish exchange between upstream and lower stream,however a large water surface became before the dam supported a better condition for fish growth,it seems balance in positive and negative action.The conclusion is that those dam building or designed would be stop or delay in order to maintain fish population and aquatic ecological balance. 相似文献
7.
Waste water treatment on freshwater fish farms is problematic as waste material and water flows can vary greatly on a daily
basis, and, in terms of effluent standards, fish farm effluent represents a dilute waste water output. A study was undertaken
to investigate in detail the nature of the waste outputs under field conditions. Waste water samples were split by meshes
into the following size ranges: >200μm, 200-100μm, 100-60μm, 60-30μm and <30μm. Waste water quality parameters, suspended
solids (SS), biochemical oxygen demand (BOD5) and total phosphorus (TP) were examined for each size range at two freshwater fish farm sites in Scotland, as part of a
wider investigation into waste water quality of aquaculture operations. Results indicated that during periods of peak waste
output i.e. tank cleaning, approximately 80% of BOD5 and SS was present in a particle size range of 100-60μm, but only 66% of TP transport occurred in this size range. At other
times, low levels (≤40%) of entrapment of wastes by the chosen meshes was observed, suggesting a reversion to predominantly
dissolved material transport. Compared against a larger data set of outflow concentrations obtained from another section of
the study, maximum removal rates of 46%, 48% and 30% for BOD5, SS and TP respectively were determined. The implications for waste water treatment at fish farms are discussed. 相似文献
8.
鱼粉在水产饲料中的应用研究 总被引：6，自引：0，他引：6
As a main protein source in aquafeeds, fish meal has been extensively studied. Fish sources, freshness, processing temperature, lipid quality and microbiological index are five main aspects of the evaluation of fish meal quality. This paper reviewed the researches on fish meal including the evaluation of fish meal quality, the use of fishmeal and the environmental problems. Biogenic amine is the main potential toxin in decomposed fish meal including mainly histamine, cadaverine, putrescine and tyramine and most studies showed that they could affect the fish growth performance and health. The determination of protein digestibility of fish meal includes pepsin-digestion method, animal test, capillary electrophoresis, etc. The content of phosphorus in fish meal and its utilization can introduce pollution to water bodies and the use of alternative protein and improvement of utilization of fish meal can help to reduce the pollution from fish meal. 相似文献
9.
真鲷天然抗性相关巨噬蛋白全长cDNA的克隆与序列分析 总被引：1，自引：0，他引：1
Natural resistance associated macrophage protein (Nmmp) is an innate resistance protein to intracellular parasites, which is expressed plentifully in macrophage ceils. Nramp has been studied in mouse, human, cattle, rainbow trout and channel catfish.However, tittle was known about the structure of Pagrus major Nramp. In order to get the complete sequence of Pagrus major Nramp, a pair of primer is designed according to a 200bp known sequence of Pagrus major Nramp cDNA. By the use of SMART RACE, the full Nramp of Pagrus major cDNA about 5 000 bp was obtained, including about 200 bp 5‘ terminal region (UTR),complete encoding region and 3‘ terminal region. There were 3 ployA signals, which showed many possibilities of cutting at 3‘ terminal region. The character of Pagrus major Nramp nucleotide sequence and deduced amino acid sequence are analyzed. 12 putative transmembrane(TM) regions, a consensus transport motif (CTM), a predicted protein kinase C phosphroylation site and three predicted N-link glycosylation sites are indicated in its deduced amino acid sequence. The ‘consense transport motif‘ CTM is located etween TM8 and TM9. Furthermore, a protein kinase C phosphroylation site and three N-link glycosylation sites were predicted. The lignment of amino acid sequences between Pagrus major Nramp cDNA and several animals is analyzed and the deduced amino acid equence of Pagrus major Nrarnp had 77.8%, 83.0%, 82.3%, 80.0%, 81.1%, 60.4%, 70.3%, 58.5%, 69.5% identity ith rainbow trout α(AAD20721), rainbow trout β(AAD20722), channel catfish(AF400108), fathead minnow (AAF01778),common carp (CABal96), mouse 1 ( AAA39838 ), mouse 2 ( AAC42051 ), human 1 ( D50403 ), human 2 ( NP - 0(106(18 ),respectively. The alignment reveals high conservation in TM and CTM regions. Analysis result makes us get familiar with the structure nd character of fish Nramp, furthermore, offers some infonnat/on for the enhancement of immunity of fish and genetic amelioration on fish breeding. 相似文献
10.
水产食品特定腐败菌与货架期的预测和延长 总被引：25，自引：2，他引：25
Fresh fish and lightly preserved fish products are welcome by the global market, however, they are also among the most perishable food products. The research on specific spoilage organisms (SSO) reveals the spoilage process of aquatic product. This paper reviews the current knowledge (past ten years) on SSO of fresh fish and lightly preserved fish products with particular emphasis on characteristics of SSO and how to apply this concept to determine, predict and extend the shelf life of aquatic product. During storage, the microflora changes owing to different abilities of the microorganisms to tolerate the preservation conditions. SSO is defined as special microorganisms which can increase rapidly during preservation and has the ability to produce off- odours and off- flavours associated with spoilage, and spoilage metabolites. Identification of an SSO relies on comparison of the sensory and chemical characteristics of spoiled product with those of isolates from the spoilage microflora. Generally, the SSO of fresh fish may be a single species or genus, but the ones of lightly preserved fish products will be more complex. One exciting area for use of SSO aims to obtain quantitative knowledge about probable behavior of SSO and their function during the progression of spoilage. Thus mathematical models on the growth of SSO are established to evaluate the quality lost degree of product, which provide a sound information for the rational development of devices to monitor loss of products shelf life. Models for the growth of Pseudomonas spp, S. putrefaciens, P. phosphoreum have been established, and validated for shelf life prediction of seafood successfully. Another application field of SSO intends to develop the techniques to prolong the shelf life of food products by inhibiting SSO targetedly. Targeted inhibition of spoilage bacteria during preservation reduces their growth and results in a significant extension of shelf life in despite of the activity of non - spoilage organisms has not been influenced. Such techniques have been applied in perversion field of fresh fish and lightly preserved fish. 相似文献
11.
Spatial structure of co-occurring anchovy and sardine populations from acoustic data: implications for survey design 总被引：10，自引：0，他引：10
A geostatistical analysis has been undertaken on the spatial structure of co-occurring adult and recruit populations of anchovy, Engraulis capensis , and sardine, Sardinops sagax , in the southern Benguela upwelling region, using information from two acoustic surveys. The study was prompted by the need for a more efficient design for surveying sardine abundance, which is increasing in relation to that of anchovy; the current acoustic survey design is based on the distribution of anchovy. Variograms of fish density and density indicator variables were computed, as well as cross-variograms between the indicator variables. The sardine variograms were less structured than the anchovy variograms, with slightly greater nugget effects, indicating greater randomness in space at small scales. The indicator variograms showed progressive loss of structure with increasing density. Anchovy formed high-density schools during the day, breaking into larger, low-density aggregations at night. Sardine, on the other hand, remained in relatively high-density schools throughout the day. The cross-variograms revealed some spatial continuity between low- and high-density areas for anchovy, but no such transitional structures were evident for sardine. It was concluded that sardine are more patchily distributed than anchovy and, unlike anchovy, they may not have a single common way of occupying space at the population level, perhaps partly because of the broader age structure of the population. It is concluded that, while the current acoustic survey design is well suited to the spatial distribution of anchovy, it is not as well suited to that of sardine. Future survey designs should be more tailored to the spatial distribution of sardine, possibly by using sampling methods to cope with the highly patchy distributions expected. 相似文献
12.
鱼类体长-体重关系参数估计的准确与否影响进一步的渔业资源评估和管理。不同采样设计获得的生物学数据,对鱼类体长-体重关系参数b估计可能会有一定的影响。本文基于2013-2014年在黄河口水域调查获得的矛尾虾虎鱼(Chaemrichthys stigmatias)体长、体重数据,采用计算机模拟重抽样方法,选取相对估计误差和相对偏差两个指标,比较了不同采样设计对估计矛尾虾虎鱼体长-体重关系参数b的影响。结果表明,增加样本量可有效提高其体长-体重关系参数b的估计精度。不同季节数据对参数估计精度具有不同影响,应用多季节调查采样数据估计参数精度往往优于单季节采样。夏季数据对矛尾虾虎鱼体长-体重关系参数估计尤为重要。方案9(夏-冬季方案)在样本量达到540尾时,相对估计误差REE为2.08%,相对偏差RB的绝对值为0.71%,在相同样本量下该设计方案表现最好。在估计黄河口矛尾虾虎鱼等鱼类体长-体重关系参数时,应保证获得一定样本量的对参数估计具有较大影响的季节的生物学数据。 相似文献
13.
鱼类体长数据较易获得,常用于数据有限的渔业资源评估和管理,且基于鱼类体长的指标可以作为渔业生态系统的生态监测指标。本文根据山东半岛南部海域底拖网季度调查收集的方氏云鳚体长数据,应用计算机模拟重采样方法,研究了调查站位数对估计方氏云鳚（Enedrias fangi）体长频率分布和平均体长的影响。结果表明,在各个季节,方氏云鳚体长频率分布离散指数（DI）变化范围为0~0.91,大部分站位的DI值为0.75~0.90,说明调查站位间体长频率分布较为相似,可以对调查站位数进行优化,提高采样效率;调查站位越多,体长频率分布和平均体长估计精确度越高;由于对不同体长数据指标估计的精度不同,用以估计体长频率分布和平均体长的样本量存在差异;20个和30个调查站位分别为估计方氏云鳚体长频率分布和平均体长的可接受样本量。本研究结果可为基于不同体长指标的渔业资源调查设计提供一定的理论支撑,有助于对基于体长指标有效站位数的初步了解,为山东半岛南部海域的鱼类资源科学调查和科学管理提供参考。 相似文献
14.
基于2000年6月和2014年11月黄海南部采集的浮游动物和不同生长阶段鳀(Engraulis japonicus)的胃含物(饵料)组成分析资料,研究鳀的饵料粒级分布与摄食粒级选择性及其与环境生物组成的关系,旨在推进粒级在传统摄食生态分析中的应用。结果显示:黄海南部鳀的饵料种类组成与环境中生物种类组成有关;各体长组中,鳀的饵料粒级多样性与种类多样性分布趋势相似;体长为110 mm左右的鳀的饵料种类多样性和粒级多样性水平最高;鳀的饵料粒级均值随鱼体体长增加而增加;体长约为30 mm和≥70 mm的鳀有明显的饵料粒级转换。根据上述结果,认为在鳀胃含物分析过程中,整合环境中饵料生物的相对组成和粒级大小,可有效评价鱼类对饵料的粒级选择性。 相似文献
15.
Environmental and biological monitoring for forecasting anchovy recruitment in the southern Benguela upwelling region 总被引：3，自引：1，他引：2
S. J. PAINTING L. HUTCHINGS J. A. HUGGETT J. L. KORRÛBEL A. J. RICHARDSON & H. M. VERHEYE 《Fisheries Oceanography》1998,7(3-4):364-374
Environmental and biological sampling and monitoring have been carried out in the southern Benguela since 1988. The overall goal of this research is to investigate environmental factors affecting anchovy recruitment and to develop the ability to forecast anchovy recruitment from year-to-year using field data obtained during the spawning season (August to March). Sampling was conducted at three different temporal and spatial scales: during annual (November) broad-scale hydro-acoustic surveys to determine spawner biomass on the entire spawning ground and in the core transport and recruitment areas; during monthly surveys in the core spawning, transport and recruitment regions over two entire spawning seasons (1993/94 and 1994/95); and during weekly sampling (since 1995) along a single transect downstream from the spawning area. Annual surveys provide the best spatial coverage, but are inadequate for representing environmental conditions and anchovy spawning success over a prolonged season. Weekly sampling provides the best temporal coverage, but logistical constraints restrict information to a limited portion of the spawning area and a reduced number of variables. Monthly surveys provide intermediate coverage in time and space, but are expensive and labour-intensive. Forecasting anchovy recruitment has been based on two different approaches: the establishment of empirical relationships, and the development of rule-based expert systems. Forecasts from deterministic expert systems have compared well with final estimates of recruitment strength, and indicate that environmental and biological variables may be used in a structured way to forecast anchovy recruitment. 相似文献
16.
Hiroto Murase Atsushi Kawabata Hiroshi Kubota Masayasu Nakagami Kazuo Amakasu Koki Abe Kazushi Miyashita Yoshioki Oozeki 《Fisheries Science》2012,78(4):761-773
The distribution pattern and biomass of the Japanese anchovy Engraulis japonicus in the offshore region of the western North Pacific (north of 35°N and west of 170°E) were studied using a quantitative echosounder. This is the first attempt at such a study in this region. Data were collected in summer from 2004 to 2007. The biomass was estimated using data collected at 38?kHz. Species compositions in the backscatterings from pelagic fish were assigned based on the results of trawl hauls taking account of sea surface temperature (SST). Japanese anchovy tended to be high density to the west of 153°E and were distributed in an SST range of 9?C24?°C. Although the temporal and spatial coverage of the survey differed each year, at least 1.5?C3.4 million tons of Japanese anchovy were present in the survey area between 2004 and 2007. To take account of the spatial coverage of the survey each year, the most reliable biomass estimate for this region in the time period was 3.4 million tons (coefficient of variation?0.22). 相似文献
17.
Guillermo Boyra Marian Peña Unai Cotano Xabier Irigoien Anna Rubio Enrique Nogueira 《Fisheries Oceanography》2016,25(5):529-543
In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas. 相似文献
18.
We attempted to estimate the survival rates of larval cohorts (3–15 mm in body length) of the Japanese anchovy Engraulis japonicus population in Hiuchi‐nada, Seto Inland Sea, Japan, and examined the relationship to their food availability. The survival rates were directly calculated from the change in larval density during the survey. The estimated daily survival rate ranged between 0 and 89% d−1, but increased with the increase in the mean concentration of small‐sized copepod nauplii (<100 μm in body length) sampled at 10 m depth. When the food concentration was higher than about 5 nauplii L−1, the daily survival rate of larval anchovy reached an asymptote of approximately 89% day−1. It might be possible to provide a framework for the forecast for larval abundance immediately prior to recruitment size (10–15 mm SL), based on larval abundance of the monitored size (3–8 mm SL) and the survival rate which is estimated from the concentration of small‐sized nauplii. 相似文献
19.
The spatial extent of small pelagic fish spawning habitat is influenced by environmental factors and by the state of the adult population. In return, the configuration of spawning habitat affects recruitment and therefore the future structure of the adult population. Interannual changes in spatial patterns of spawning reflect variations in adult population structures and their environment. The present study describes the historical changes in the spatial distribution of spawning of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) in the Bay of Biscay during two periods: 1967–72 and 2000–2004. Using data from egg surveys conducted in spring, the spatial distributions of anchovy and sardine eggs are characterized by means of geostatistics. For each survey, a map of probability of egg presence is constructed. The maps are then compared to define (1) recurrent spawning areas, (2) occasional spawning areas and (3) unfavourable spawning areas during each period. Sardine spawning habitat is generally fragmented and appears spatially limited by the presence of cold bottom water. It is confined to coastal or shelf break refuge areas in years of restricted spawning extent. For anchovy, recurrent spawning sites are found in Gironde and Adour estuaries whilst spawning can extend further offshore in years of more intense spawning. For both species, the mean pattern of spawning has changed between 1967–72 and 2000–2004. Noticeably, the spatial distribution of anchovy eggs in spring has expanded northward. This trend possibly results from changes in environmental conditions during the last four decades. 相似文献
20.
Large amplitude variations in recruitment of small pelagic fish result from interactions between a fluctuating environment and population dynamics processes such as spawning. The spatial extent and location of spawning, which is critical to the fate of eggs and larvae, can vary strongly from year to year, as a result of changing population structure and environmental conditions. Spawning habitat can be divided into ‘potential spawning habitat’, defined as habitat where the hydrographic conditions are suitable for spawning, ‘realized spawning habitat’, defined as habitat where spawning actually occurs, and ‘successful spawning habitat’, defined as habitat from where successful recruitment has resulted. Using biological data collected during the period 2000–2004, as well as hydrographic data, we investigate the role of environmental parameters in controlling the potential spawning habitat of anchovy and sardine in the Bay of Biscay. Anchovy potential spawning habitat appears to be primarily related to bottom temperature followed by surface temperature and mixed‐layer depth, whilst surface and bottom salinity appear to play a lesser role. The possible influence of hydrographic factors on the spawning habitat of sardine seems less clear than for anchovy. Modelled relationships between anchovy and sardine spawning are used to predict potential spawning habitat from hydrodynamical simulations. The results show that the seasonal patterns in spawning are well reproduced by the model, indicating that hydrographic changes may explain a large fraction of spawning spatial dynamics. Such models may prove useful in the context of forecasting potential impacts of future environmental changes on sardine and anchovy reproductive strategy in the north‐east Atlantic. 相似文献