鲑科鱼类及其养殖状况

本文介绍鲑科鱼类及其主要生物学特点、鲑科鱼类在世界渔业经济中的重要地位和养殖产业技术发展现况。鲑科鱼类属典型的冷水性鱼类,高蛋白、富含不饱和脂肪酸、营养丰富、可食部分大、无肌间刺、易加工,是欧美人民的传统水产食品和重要养殖鱼类。鲑鱼是世界三大养殖鱼类之一,其养殖产量仅在鲤鱼和罗非鱼之后,海水鱼类养殖中,半数以上(54.3%)来自鲑鱼产量。2005年,世界鲑鱼产量280万吨,其中195万吨(69.6%)来自人工养殖。本文也简要叙述了我国鲑鱼养殖的历史和现状,以及在鲑鳟鱼类遗传育种、养殖新品种开发、营养与饲料、病害防治、繁殖期调控等方面的研究进展,并针对我国鲑鳟鱼产业发展存在的问题提出了建议。     

鲑鱼传染性胰脏坏死病临床诊断及检测

鲑鱼传染性胰脏坏死病（infctious pancreatic necrosis in trout，IPN）是鲑科鱼类的一种高度传染性的急性病毒疾病。该病主要病症是胰脏坏死。该病于1940年首次发现于加拿大的鲑科鱼，目前已遍及欧洲、亚洲和美洲等。     

世界鲑科鱼类养殖技术的现状

鲑科鱼类有两个属,即鲑属和大麻哈鱼属。鲑属只有鲑一个种,而大麻哈鱼属则有六个种,即:大麻哈鱼、银大麻哈鱼、大鳞大麻哈鱼、细鳞大麻哈鱼、红大麻哈鱼和马苏大麻哈鱼。本文简要地介绍了当前世界各国养殖鲑科鱼类方面的现状,有助於我们对它有一个整体的了解,也有助於我们开展鲑科鱼类养殖时参考。     

渔业纵览

为促进鲑鱼类增养殖业的持续发展,中国水产学会与北京顺通虹鳟养殖中心定于2005年10月20～22日在北京举办“中日鲑鱼类增养殖技术学术报告会”。会议将邀请日本著名水产学家隆岛史夫先生做学术报告:①世界鲑鱼类的发展趋势与展望;②鲑、鳟鱼类增养殖生物学研究;③鲑鱼类遗传育种新技术。邀请国内专家做学术报告:1.我国鲑鱼类养殖新品种开发及养殖新技术;2.鲑科鱼类流行病学及药物的安全使用;3.鲑鱼类的高效养殖;4.西南地区鲑鱼类养殖现状与发展对策;5.白鲑属鱼类及其增殖途径的探讨;6.云南冷水鱼养殖发展现状及对策。欢迎从事鲑科鱼类科研、…     

鲑鱼类养殖史料

我们查阅国内外有关鲑鱼类方面的资料，目的是为移值大西洋鲑的试验研究提供依据。现将有关资料归纳整理成“大西洋鲑的起源”、“大西洋鲑的生物学”、“鲑鱼类养殖史料”和“大西洋鲑的人工养殖”等文章，供研究鲑鱼类的同行们参考，同时也为发展我国鲑鱼类养殖业积累些基础资料。鱼类养殖是一种古老的技术，中国人在公元前2000年就开始从事鱼类繁殖，在池塘里能够繁殖多种鱼。现在世界上养鱼发达的日本养殖技术就是从中国引进的。蛙鱼类的养殖是在几百年前随着太平洋鲑和大西洋鲑资源量的减少，为了增加和恢复其种群数量而发展起来的。早…     

大豆粕在鲑鳟鱼类饲料中的利用（一）

一、前言 大西洋鲑鱼、太平洋鲑鱼以及虹鳟统称为鲑鳟鱼类。由于他们价位较高，但为相对容易养殖的鱼类，所以成为世界上主要养殖的肉食性鱼类。鲑鱼与鳟鱼可存活于各种不同的养殖环境，某些鳟鱼可在0℃到28℃的水温之间生存，     

几种鲑鳟鱼类摄食习性及投喂技术

鲑鳟鱼是优质的冷水性鱼类 ,欧美国家养殖极为普遍。我国从上世纪 5 0年代开始养殖虹鳟 ,主要集中在北方地区。随着渔业生产技术的不断发展 ,我国鲑鳟鱼类的养殖范围 ,正由北方向南方扩展 ,养殖品种也由单一的虹鳟鱼扩大到金鳟 ,白点鲑 ,银鲑 ,大西洋鲑 ,等等。虽然这些鱼类都属鲑科 ,但是它们摄食习性相差很大 ,在生产中必须采取不同的投喂方式。1　虹鳟。虹鳟是养殖时间最长的鲑科鱼类 ,已经完全驯化。虹鳟性凶猛 ,贪食 ,能在水面、水中和池底摄食 ,抢食激烈 ,有跟人走动索饵习性。投喂时 ,可定点成片地撒投饲料 ,一般站在池埂的中间 ,向…     

静水充氧式三文鱼人工养殖技术

银鲑和大西洋鲑均为鲑科鱼类，目前在市场上人们把鲑鱼统称为三文鱼，三文鱼是北美、欧洲、日本餐桌上最受欢迎的鱼类之一。尤其因其营养价值高、肉味鲜嫩、少脊问刺而被推为制作生鱼片的首选，是闻名世界的名贵鱼类。     

鲑科鱼类鱼卵计数方法简介

鲑科鱼类是国际渔业市场上的高档水产品，也是世界范围内最重要的养殖对象之一。我国幅员辽阔，拥有众多适合开展鲑科鱼类人工养殖的自然资源，并且我国还拥有丰富的优质鲑科鱼类种质资源，如哲罗鱼、细鳞鱼和黑龙江茴鱼等。随着人们生活水平的不断提高，对优质鱼类的消费需求日益增多，鲑科鱼类养殖得到了较快发展，并取得了良好的经济效益。目前在东北地区和内蒙古、甘肃、新疆、山东、山西、福建、四川、云南等地鲑科鱼类养殖蓬勃发展。     

冰水女皇—七彩鲑鱼

七彩鲑鱼（Salvelinusfontinalis），在我国某些地区又被称为美洲红点鲑，是世界上著名的五种鲑鱼之一（其它四种分别是：北极鲑、雷克鲑、多丽鲑和公牛鲑）。七彩鲑鱼主要分布在加拿大东部以及美国东北部大部分水域，是广盐性淡水三文鱼。在加拿大和美国西部山区也有分布。近年来随着人们对七彩鲑鱼越来越多的认识，它也就逐渐被传播到其他国家了，如南美或欧洲很多国家。七彩鲑鱼色彩鲜艳，体质强健，拼抢凶猛，嘴大牙坚，咬合有力，深受钓鱼爱好者的青睐。七彩鲑鱼还具有肉质坚实、味道鲜美、营养丰富的特点。烹、烤、煎、炸、蒸、炖、…     

Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean

The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.     

Protein and amino acid composition from the mantle of juvenile O ctopus vulgaris exposed to prolonged starvation

Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg^?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg^?1 protein) than essential amino acids (425.82 ± 9.15 g kg^?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.     

Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies

Plasma estradiol-17 (E₂), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E₂ and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E₂ and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.     

Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide

Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.     

An overview of stress physiology of fish transport: changes in water quality as a function of transport duration

This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO₂ and ions should be more often evaluated. Plasma Na⁺ and Cl^‐ are very useful markers of acidosis, due to their respective exchange for H⁺ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.     

Are hatchery‐reared abalone naïve of predators? Comparing the behaviours of wild and hatchery‐reared northern abalone,Haliotis kamtschatkana (Jonas, 1845)

Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.     

Effects of cadmium on the kinetics of calcium uptake in developing tilapia larvae, Oreochromis mossambicus

The toxic effects of Cd²⁺ on Ca²⁺ influx kinetics in developing tilapia (Oreochromis mossambicus) larvae were evaluated. Addition of 20 µg l^-1 of Cd²⁺ to the environment of 0 and 3 day-old larvae competitively inhibited the Ca²⁺ uptake within 4h resulting in a great increase in K_m values for Ca²⁺ influx (19.3 and 17.4 fold, respectively) as compared with their respective controls. Consequently, the actual Ca²⁺ influx of larvae in solutions of 0.2 mM Ca²⁺ are suppressed by 32–45%. Also, 3 day-old larvae were more sensitive to internally accumulated Cd²⁺ than 0 day-old larvae. Although the Ca²⁺ influx in 0 and 3 day-old larvae may be restored to the levels of their respective controls with 24h of being transferred to a 20 µg l^-1 Cd²⁺ solution, total body Ca²⁺ content was significantly reduced in 3 day-old larvae. Increased Ca²⁺ uptake efficiency ensures sufficient Ca²⁺ for normal growth. However, rapid increase in Ca²⁺ influx after hatching also leads to higher Cd²⁺ uptake. Exposure to Cd²⁺ will lead to a drop in body Ca²⁺ content resulting in retardation of larval growth. Therefore, we conclude that if Ca²⁺ uptake is interfered with at this critical stage of development, larvae will not be able to maintain normal levels of body Ca²⁺ and will show signs of Cd²⁺ poisoning.     

Migratory dynamics of stream-spawning longnose gar (Lepisosteus osseus)

Abstract– Literature evidence suggests that lake-dwelling longnose gar (Lepisosteus osseus) enter tributary streams to spawn, Until the present study, the dynamics of this breeding migration had never been investigated quantitatively. During the summers of 1991 and 1992, longnose gar were captured as they entered Weaubleau Creek, Missouri, a tributary of Harry S. Truman Reservoir. The in-stream spawning migration began in early April and ended in late May, and was positively correlated with stream flow and water level, and negatively correlated with water temperature. In-stream residence times ranged from 15 to 94 days, with males exhibiting longer residence times than females. Once in-stream, longnose gar travelled as far as 10 km upstream and occupied certain pools at greater relative frequencies. Although the reason for this preferential utilization is not completely understood, it may relate to pool depth and riffle proximity. Longnose gar disperse from the spawning stream great distances, with gar captured in Weaubleau Creek being recaptured up to 48 km away. This information should provide fisheries biologists the means to consider the reproductive ecology of this species in their conservation and management decisions.     

Nutritional regulation of hepatocyte fatty acid desaturation and polyunsaturated fatty acid composition in zebrafish (Danio rerio) and tilapia (Oreochromis niloticus)

The desaturation and elongation of [1-¹⁴C]18:3n-3 was investigated in hepatocytes of the tropical warm freshwater species, zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus). The hepatocyte fatty acid desaturation/elongation pathway was assayed before and after the fish were fed two experimental diets, a control diet containing fish oil (FO) and a diet containing vegetable oil (VO; a blend of olive, linseed and high oleic acid sunflower oils) for 10 weeks. The VO diet was formulated to provide 1% each of 18:2n-6 and 18:3n-3, and so satisfy the possible EFA requirements of zebrafish and tilapia. At the end of the dietary trial, the lipid and fatty acid composition was determined in whole zebrafish, and liver, white muscle and brain of tilapia. Both zebrafish and tilapia expressed a hepatocyte fatty acid desaturation/elongation pattern consistent with them being freshwater and planktonivorous fish. The data also showed that hepatic fatty acid desaturation/elongation was nutritionally regulated with the activities being higher in fish fed the VO diet compared to fish fed the FO diet. In zebrafish, the main effect of the VO diet was increased fatty acid Δ6 desaturase activity resulting in the production of significantly more 18:4n-3 compared to fish fed the FO diet. In tilapia, all activities in the pathway were greater in fish fed the VO diet resulting in increased amounts of all fatty acids in the pathway, but primarily eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). However, the fatty acid compositional data indicated that despite increased activity, desaturation of 18:3n-3 was insufficient to maintain tissue proportions of EPA and DHA in fish fed the VO diet at the same level as in fish fed the FO diet. Practically, these results indicate that manipulation of tilapia diets in commercial culture in response to the declining global fish oil market would have important consequences for fish fatty acid composition and the health of consumers. Scientifically, zebrafish and tilapia, both the subject of active genome mapping projects, could be useful models for studies of lipid and fatty acid metabolism at a molecular biological and genetic level. This revised version was published online in August 2006 with corrections to the Cover Date.