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1.
Salmon farming is among the most successful aquaculture industries with a production growth that is substantially higher than aggregate aquaculture production in recent decades. It is well known that innovations and productivity growth are the main sources for this development. In this article we look closer at two potentially important factors in production growth, development of farm size and company size directly through economies of scale and indirectly through capacity in R&D, innovation, sales and marketing. In Norway, production per license has increased from 26 tons in 1980 to 1,130 tons in 2010, suggesting a substantial intensification in the industry. In all five leading salmon producing countries, the degree of concentration has increased and the large firms have become bigger over time.  相似文献   

2.
Aquaculture experienced a significant global expansion at the end of the 20th century, becoming one of the fastest growing sectors of animal husbandry and production during that period. Chile's contribution to world expansion of salmon and trout production was notorious, given that in a short twenty five-year period it became one of the leading world producers. One prominent feature of salmon production in Chile is that the industry concentrated geographically in a limited area around Puerto Montt, in Region 10 of the country. Industry concentration cannot be exclusively explained in terms of natural advantages, and evidence is presented in favour of Venables's model (1996). A qualitative analysis of the evolution of the industry is presented to provide evidence of input-output linkages, economies of scale, competition and the progressive multiplication of inputs, applying two types of data sources: a review of the existing technical literature on the subject and in-depth interviews with 20 industry experts.  相似文献   

3.
Conventional open netcage systems for salmon aquaculture are under scrutiny and criticism partially because they are believed to generate adverse environmental impacts on other resource users and the surrounding environment. One alternative to preventing or miniming these impacts is to use enclosed systems. Experience indicates that these enclosed systems are technically feasible and environmentally promising, but they are economically demanding because of high capital and operating costs. Therefore, an economic analysis of open netcage and sea-bag systems for salmon aquaculture was conducted to examine the profitability of salmon aquaculture operations between these two systems. The study shows that netcage systems are more financially profitable than sea-bag systems when environmental costs are either not or only partially considered. Sea-bag systems can be financially profitable only when they produce fish that achieve a price premium. Sensitivity analyses reveal that market price has the most important impact on the profitability of both systems; changes in discount rates, fish density, feed costs, and environmental costs also have major impacts on the profitability of netcage systems. Changes in the length of the growth cycle, survival rate, and feed conversion ratio have minor impacts on the profitability of sea-bag systems.  相似文献   

4.
Over the past two decades aquaculture has emerged as the preeminent source of salmon. The development and evolution of salmon aquaculture in Chile illustrates changes that have taken place to a greater or lesser extent in other salmon producing regions. Although initially comprised of small independent firms with heavy reliance on foreign technology and production inputs, the Chilean salmon aquaculture industry has evolved into a horizontally and vertically integrated complex of interdependent suppliers, producers, processors, distributors, and supporting entities. The structure and organization of industries evolve over time in response to changes in the price and availability of inputs, changes in the demand for outputs and output attributes, and changes in technology. The growing demand for traceability and assurance is a change in the demand for credence attributes. Firms that are able to organize to provide traceability and assurance at low cost will, ceteris paribus, have an advantage.  相似文献   

5.
Abstract

Commercial salmon and trout farming has emerged as a major industry in Chile during the 1990s. Salmon is not a native species to Chile, still excellent climatic conditions are provided for farming. Since 1992 Chile has been the second largest producer of farmed salmon and trout in the world after Norway. This report reviews the development of the Chilean salmonid industry from its early stages until today with respect to production patterns, legislation and main markets. A cost comparison between Chilean and Norwegian farmed salmon is also provided. Finally, the international competitiveness and future challenges of the Chilean salmonid farming industry are analysed.  相似文献   

6.
This study uses a conjoint experiment to evaluate seafood consumers’ preferences for wild versus farmed seafood in Rhode Island, while providing an option for farmed products to be certified for best aquaculture practices, focusing upon salmon and shrimp. The definition for best aquaculture practices provided to respondents in the survey is broadly based upon standards currently in use by aquaculture certification groups, highlighting sustainability of fish feed, and control of antibiotic use, water quality and stocking density. Using data from an in-person intercept survey, a conditional logit model shows that a sample of 250 seafood consumers in Rhode Island choose wild products over farmed even when farmed products are certified, and by an entity preferred by the consumer. Results warrant both further study of consumer preferences for certified aquaculture products across a broader population, and study of the effect of different explanations of ‘best aquaculture practices’ upon preferences.  相似文献   

7.
大西洋鲑性腺分化及热休克的影响   总被引:7,自引:2,他引:7  
大西洋鲑性腺分化发生在孵出45-63天,约495-693度日。经热休克处理获得三倍体稚鱼,性腺在分化之前明显大于正常二倍体。雌性三倍体稚鱼性腺在细胞学分化时受抑,初级卵母细胞不能发育;雄性三倍体稚鱼性腺在细胞学分化阶段生长明显减慢,初级精母细胞尚能发育。  相似文献   

8.
绥芬河驼背大麻哈鱼移殖放流及回归效果的初步研究   总被引:3,自引:0,他引:3  
本文首次报道驼背大麻哈鱼人工放流及其回归效果。根据驼背大麻哈鱼具回归母河川的生物学特异性,在注入日本海的绥芬河水系进行移植放流试验。1988年4月放流稚鱼72万尾,1989年6~8月放流群体回归母河川,在我国境内河区重捕回归成鱼 647尾,比该水系自然群体猛增约30倍,回归率为0.087%,标志回归率为0.023%。该项放流试验效果显著,为绥芬河水系驼背大麻哈鱼资源增殖提供重要的科学依据。  相似文献   

9.
Abstract

In this paper, a time-varying student-t copula is used to capture information on price volatility dependence in the short-, medium-, and long-run horizon in the US market for frozen and fresh salmon, trout, tilapia and catfish. Using monthly data from July 1992 to March 2017, the volatility dynamics for these aquaculture species are assessed. The analysis allows indicating significant differences in the volatility relationships, depending on time-frequency. While short-run volatility has limited dependency, there is significant dependency in both the medium- and long-run, indicating that market integration is stronger in the long-run. The information is particularly important to buyers and producers utilizing the futures markets, as contracts are typically traded using a set of frequencies, and may help them manage and reduce price risk.  相似文献   

10.
Research on management practices in fish farming has traditionally focused on two topics: production planning and forecasting of prices. This article combines these two areas of research, and illustrates how information on price patterns can change production plans, and hence increase the value of the farm enterprise. It will present a model farm and illustrate, with different levels of price information, how information on future prices alters the original production plan and hence creates extra value for the farmer. Although the specifics and empirical application of the paper are on salmon and salmon farming, the ideas and general results could be applied to all farmed species.  相似文献   

11.
Intensive aquaculture, especially the production of carnivorous species requires artificial feeding. Marine proteins are preferred to vegetable proteins, since fishmeal and oil provide the essential nutrients required by farmed fish. Given the stagnant production of industrial species and the rapid increase in aquaculture production, fishmeal availability would pose a biological constraint on aquaculture contribution to world fish supplies in the future, unless alternative feed sources can be incorporated in diets. In this paper, the technical substitutability between fish and vegetable-based feeds for salmon and trout are assessed through the estimation of Morishima elasticities of substitution. These are derived from a meta-analysis production function based on a large number of published feed trials. The results suggest that vegetable oil may be a potential substitute for fish oil, particularly in salmon aquaculture, but fishmeal is likely to remain a necessary component of feed unless some new feed source can be developed.  相似文献   

12.
赵维信  R.S.Wright 《水产学报》1986,10(4):388-394
提要应用大麻哈鱼(Oncovhynchus keta)促性腺激素(GTH)诱发大西洋鲑(Salmosalar)卵黄发生期的离体卵巢滤泡(直径为3.4毫米)产生性类固醇激素的研究表明,不论用0.1或1微克/毫升GTH刺激,经培育10天后,未出现卵母细胞卵核消失的现象,卵核偏位也不明显。对培养液中17α,20β-双羟孕酮(17α20βP)的积累浓度测定结果,仅1微克/毫升GTH组含少量的17α20βP;0.1微克/毫升GTH组,培养液中雌二醇的积累浓度明显高于对照组和1微克/毫升GTH组,并为后者的两倍。除雌二醇外,孕酮,17α-羟孕酮,17α20βP,雄烯二酮和睾酮的产生,都呈现对GTH剂量的依赖关系,1微克/毫升GTH组的产生量明显高于0.1微克/毫升GTH组和对照组。离体研究的结果表明,处于卵黄发生期的卵巢滤泡对低剂量(0.1微克/毫升)和高剂量(1微克/毫升)GTH的反应不同。低浓度的GTH,引起性类固醇激素生物合成的途径沿着形成雌二醇的方向进行,雄激素被芳香化成雌激素,雌二醇再而刺激肝脏合成卵黄物质的前体,从而促进卵黄发生。高浓度的GTH,有抑制雌二醇合成的作用,而是促使卵母细胞向着最终成熟的方向发展,使性类固醇生物合成的途径转向形成大量雄激素和孕激素,特别是17α20βP。这与已充分生长和卵黄积累完成的卵巢滤泡离体试验的结果一致,与活体观察以上各种性类固醇激素的变化一致。  相似文献   

13.
The goal of this research was to shed light on the trade-offs that salmon consumers make between five types of production and health attributes of farmed salmon. In Canada, the major southern Ontario market cleaved into five distinct consumer segments that varied according to age and income, ‘tastes’, and threat perceptions. There was strong consumer aversion to increased levels of PCBs, even when increased contamination levels were well within Health Canada guidelines. Both contaminant avoidance and polyunsaturated fatty acid health benefits were generally more important to consumers than improved environmental performance in salmon farming production practices. The strong consumer preferences for reduced levels of PCBs in salmon flesh suggest that there could be a substantial market premium for farmed salmon produced using reduced levels of fish meal and fish oils in salmon feed. This could, by association, increase the environmental sustainability of salmon farming.  相似文献   

14.
本首次报道了陆封型大西洋鲑发眼卵孵化技术,孵化水温3-11℃,积温达到140-221度日破膜孵出稚鱼,孵化率北京房山87.6%,黑龙江渤海81.9%,经21-28d胚后发育上浮平游开食。同时介绍了苗种培育技术和管理方法。  相似文献   

15.
本文通过对大西洋鲑的完整卵泡(包括卵母细胞、外周的鞘膜细胞和颗粒细胞)、手术分离的鞘膜细胞以及分离的颗粒细胞分别进行离体培育,测定它们在促性腺激素(GTH)刺激下,释放性激素的能力。实验证明,完整卵泡具有释放孕酮,17α—羟孕酮,雄烯二酮,睾酮,雌二醇和17α20β—双羟孕酮的能力。分离的鞘膜细胞只能释放前四种性激素。分离的颗粒细胞不能释放以上任何一种性激素。结果说明,单独的鞘膜细胞或单独的颗粒细胞都不具有合成雌二醇和17α20β—双羟孕酮的能力。  相似文献   

16.
Price volatility has an important impact on seafood markets and the aquaculture industry. This article investigates price volatility regimes along three dimensions; technology, species and product form. We identify regimes using the Iterated Cumulative Sum of Squares (ICSS), which allow us to compare the volatility found in aquaculture products, as well as comparing against fish-meal and soybeans. The results help identify the level of price risk found within the aquaculture industry across species and products. In addition, we differentiate between technologies comparing wild-caught fish with aquaculture products. The results also help us consider the relative riskiness of aquaculture compared to other industries. The results indicate that in aggregate, price volatility for aquacultured products is substantially lower than for wild. However, this varies substantially between species.  相似文献   

17.
Risk analysis provides a logical strategy for the identification of hazards in an area of concern leading to their management. This approach has rarely been used for research studies on the possible links between salmon lice in fish farms and variations in wild salmonid populations. Although correlation has been found between some data sets, a series of international meetings of experts has not been able to establish cause–effect relationships between lice on farms and the current low level of salmonid stocks in Europe and eastern Canada. Research in this area is currently in progress in western Canada. Views on the meaning of the correlations found have become highly polarized in both the scientific and non‐scientific communities, with the same data often being interpreted in different ways. Farm lice levels are being managed by industry codes and by official strategies in Europe, but these programmes have not so far resulted in associated benefit to the size of wild salmonid stocks. The large array of factors that cause variations in both the size of fish stocks and the level of fish diseases is frequently overlooked. Using a risk analysis approach, the key contributory factors may be identified and appropriate remedial management actions designed to meet achievable objectives. Regular assessment of the effectiveness of the measures introduced would then be possible.  相似文献   

18.
During the last decade there has been a number of conflicts in relation to the trade of salmon in the EU. A 5-year agreement between Norway and the EU including an import constraint and a voluntary minimum import price agreement for exporter just expired, with a 13% tariff to be paid by exporters that do not accept the agreement. A year after the agreement expired, there are again calls for safeguard measure to protect EU-producers. We investigate the expected welfare effects of this tariff by analyzing a general equilibrium demand curve. In contrast to earlier studies we use a derived demand approach rather the consumer demand as most available data are at the trade level. The results indicate that only Norwegian exporters are beneficial to target for EU producers. The total welfare effect of the tariff depends critically on the supply structure of EU and Norwegian salmon.  相似文献   

19.
A bioeconomic model of reservoir aquaculture in northern Vietnam is used to investigate the impacts of fish price and yield variability on the level and riskiness of expected net revenue. Net revenue is volatile compared with similar enterprises in other countries, mainly due to high yield variability. This reflects the nascent nature of the industry in Vietnam and the potential for efficiency and productivity improvements. Increasing production intensiveness, as well as reservoir size, was found to increase profits and decrease revenue risk. Among the management parameters studied, expected net revenue was found to be most sensitive to the length of the production cycle and to the harvest rate, while revenue risk was most sensitive to cycle length. Reservoir size was found to affect net revenue less than anticipated. Although common carp monoculture was found to maximize expected profit, the current species mix minimizes risk, thereby suggesting high risk aversion by northern Vietnam's poor farmers.  相似文献   

20.
The economic effects of the implementation of regulations on aquaculture farms in the United States, while of concern, are not well understood. A national survey was conducted of salmonid (trout and salmon) farms in 17 states of the United States to measure on‐farm regulatory costs and to identify which regulations were the most costly to this industry segment. The response rate was 63%, with a coverage rate of 94.5% of the U.S. production of salmonids. The regulatory system resulted in increased national on‐farm costs of $16.1 million/year, lost markets with a sales value of $7.1 million/year, lost production of $5.3 million/year, and thwarted expansion attempts estimated at $40.1 million/year. Mean farm regulatory costs were $150,506/farm annually, or $2.71/kg; lost markets with annual sales values of $66,274/farm; annual lost production of $49,064/farm; and an annual value of thwarted expansion attempts estimated at $375,459/farm. Smaller‐scale farms were affected to a disproportionately greater negative extent than larger‐scale farms. Per‐farm regulatory costs were, on average, greater for foodfish producers than for producers selling to recreational markets, but per‐kg regulatory costs were greater for those selling to recreational compared to foodfish markets. Regulatory costs constituted 12% of total production and marketing costs on U.S. salmonid farms. The greatest regulatory costs were found to be effluent discharge regulations. The majority of regulatory costs were fixed costs, but regulatory barriers to expansion precluded compensatory adjustments to the business in spite of growing demand for salmonid products. Results of this study show that the on‐farm regulatory cost burden is substantial and has negatively affected the U.S. salmonid industry's ability to respond to strong demand for U.S. farm‐raised salmonid products. Results also suggest that the regulatory system has contributed to the decline in the number of U.S. salmonid farms. While regulations will necessarily have some degree of cost to farms, the magnitude of the on‐farm regulatory cost burden on U.S. salmonid farms calls for concerted efforts to identify and implement innovative regulatory monitoring and compliance frameworks that reduce the on‐farm regulatory cost burden.  相似文献   

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