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1.
Loreida Timberg Kadri Koppel Rain Kuldjärv Edgar Chambers IV Aussama Soontrunnarudrungsri Suntaree Suwonsichon 《Journal Of Aquatic Food Product Technology》2013,22(6):552-566
The aim of the study was to describe and evaluate competitiveness of Estonian spice-cured sprat products in Estonia and Thailand. Sample A was saltiest, Sample B had lowest overall spiciness, and Sample C had highest pepper flavor and sour taste intensity. The main drivers of consumer acceptance for the spice-cured sprat products were different: flavor and appearance in Estonia and appearance and odor in Thailand. In Estonia, one cluster of consumers liked the traditional (Sample A) and lightly spiced (Sample B) sprat products, while the other cluster liked the traditional (Sample A) and the marinated (Sample C) sprat products. In Thailand, all samples scored low, but manual clustering indicated that marinated (Sample C) sprat products are most acceptable. The current study showed that spice-cured sprat products in general can be accepted by Thai consumers, especially as part of meals, if further flavor development is carried out with the products. 相似文献
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Md. Akhtarul Alam 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):359-381
AbstractThis study examines Bangladesh fish farmers’ perception for risk sources, risk management strategies, and the relationship with socio-demographic variables. Data were collected from a sample of 350 farmers in Bangladesh. Exploratory factor analysis of a set of perception measurement items was used to assess farmers’ attitudes towards risk and their risk management strategies. The results reveal that fish-diseases, fish price variability, low quality of feed and fingerlings, flood and credit constraints were perceived as the most important sources of risk. For risk management, supply of good quality feed and fingerlings, diseases prevention, crop insurance, increasing personal savings, and assurance of bank loans were considered as the most important strategies to mitigate risks. Empirical evidence shows that farmers engage in multiple management strategies to reduce production risk. 相似文献
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Nicole Pacini Ambrosius Josef Martin Dörr Antonia Concetta Elia Melissa Scoparo Maria Cesarina Abete Marino Prearo 《Fish physiology and biochemistry》2014,40(5):1609-1619
In 2007, renal failure and death in pets were linked to pet food containing both melamine (MEL) and cyanuric acid (CYA). In mammals and fish, the co-administration of MEL and CYA causes renal crystal formation. Moreover, little is known about the process of crystal removal in fish. The aim of this study was to evaluate the formation of MEL–cyanurate crystals in kidney of rainbow trout (Oncorhynchus mykiss) fed combined MEL and CYA diets for 10 weeks at 250, 500 and 1,000 mg/kg in feed (equivalent to 2.5, 5, 10 mg/kg body weight of trout fed 1 % body weight per day). During the exposure trial and throughout a withdrawal period, prooxidant effects of MEL and CYA were evaluated on oxidative stress markers such as catalase, glutathione S-transferase and malondialdehyde. Crystal formation was dose and time dependent, and after six withdrawal weeks, crystals persisted in kidney of trout treated the highest triazine dose. Catalase and glutathione S-transferase activity in kidney of trout exposed to both triazines for 10 weeks indicated that MEL (with or without CYA) can exert a higher prooxidant effect than CYA dispensed singly. Although the enzymes activity increase appears to be reverted after two MEL withdrawal weeks, persistence of crystals may lead to severe damage in renal cells of fish. 相似文献
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Hikaru Watanabe Makoto Okazaki Tsutomu Tamura Kenji Konishi Denzo Inagake Takeharu Bando Hiroshi Kiwada Tomio Miyashita 《Fisheries Science》2012,78(3):557-567
This study represents the first quantitative analysis of the characteristics of the distribution areas and stomach contents
of common minke whale Balaenoptera acutorostrata, sei whale B. borealis, and Bryde’s whale B. edeni in relation to oceanographic and prey environments in mid summer in the western North Pacific. Common minke whales were distributed
within subarctic regions and the northernmost region of the transitional domain, coinciding with the main habitat of their
preferred prey, Pacific saury Cololabis saira. Sei whales were mainly found in the northernmost part of the transition zone and showed prey preference for Japanese anchovy
Engraulis japonica, which was significantly more abundant in the main distribution area of the whale than in its adjacent areas. “Hot spots”
of Bryde’s whales were found in several regions of the transition zone between the subarctic boundary and the Kuroshio front.
This whale species preferred Japanese anchovy as prey, for which the distribution density was significantly higher in the
main distribution area of the whale than in the adjacent areas. These results indicate that the summer distributions of Pacific
saury and Japanese anchovy greatly influence the distributions of these whale species, suggesting that the whales’ habitat
selection is closely related to their prey selection. 相似文献
5.
Václav Nebeský Tomáš Policar Miroslav Blecha Jiří Křišťan Petr Svačina 《Aquaculture International》2016,24(6):1657-1668
There has been a worldwide increase in consumption of fish from open waters and aquaculture during the last decades. In 2013, the Czech Republic was the sixth largest producer of fish within the EU, with annual production of 20,135 tonnes. However, during the period 2010–2015 import of fishery products to the Czech Republic increased from 39,098 to 43,399 tonnes. The monetary value of import increased by 81 % from 90.2 million EUR in 2010 to 169.9 million EUR in 2015. In 2010, the major imported fishery product was frozen fillets of sutchi catfish (Pangasianodon hypophthalmus) from Vietnam (8872 tonnes). In 2015, the most imported fishery product was whole chilled salmon (Salmo salar) from Norway (6897 tonnes). During 2010–2015, the export of fishery products increased from 18,167 to 22,134 tonnes, which is an increase by 21.8 %. The value of export has increased by 80 % from 54.5 million EUR in 2010 to 98.1 million EUR in 2015. The major exported fish was live common carp (Cyprinus carpio) at volume of 7545–9075 tonnes. This study looks at changes in market, volume and value of fish imported and exported during the last 6 years. 相似文献
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Primary cilia (PC) were demonstrated for the first time in fish endothelial, epithelial and fibroblast cell lines through immunofluorescence staining with the monoclonal antibody, 6-11B-1, against acetylated α-tubulin. The study was carried out with eight recently developed cell lines from the walleye, Sander vitreus (Mitchill). These were three fibroblast-like cell lines, WE-cfin11f, WE-skin11f and WE-liver3 from, respectively, the caudal fin, skin and liver, and three epithelial-like cell lines, WE-cfin11e, WE-spleen6 and WErpe from, respectively, the caudal fin, spleen and retina. Also, endothelial-like WEBA from the bulbus arteriosus and glial-like WE-brain5 from the brain were used. Immunocytochemistry revealed strong staining for acetylated α-tubulin in mitotic spindles and midbodies for all cell lines, and in PC for all cell lines except WE-skin11f. Staining of cytoplasmic microtubules (fibrils) was absent in three cell lines, including WEBA, but present in the others, especially WE-skin11f, which might have obscured PC detection in these cells. Tubacin, an inhibitor of histone deacetylase 6, induced cytoplasmic fibrils in WEBA and the intensity of their staining in WE-cfin11f. These results suggest that the cell lines might differ in their deacetylase activities, making them useful for studying this tubulin modification in teleosts, as well as for studying PC. 相似文献
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Temporal changes in growth, plasma thyroid hormone, cortisol, growth hormone (GH) and non-esterified fatty acid (NEFA) concentrations, hepatic T3 content and hepatic 5-monodeiodinase activity were measured in rainbow trout (Oncorhynchus mykiss) subjected to a sustained fast for up to eight weeks, and during a four-week re-feeding period. The purpose of the study was to examine aspects of the endocrine control of energy partitioning processes characteristic of short-term (acute; fasting) and long-term (chronic; starvation) food-deprivation states in fish, and to explore the role of the thyroid hormones, cortisol and GH in the energy repartitioning that takes place during an acute anabolic (re-feeding) state following chronic food deprivation.Differences in growth rate between fed and fasted groups were evident after two weeks, but significant weight loss by the fasted groups was not evident until between four and six weeks into the fast. Hepatosomatic indices (HSIs) were significantly reduced in the fasted fish within seven days, and as early as two days in one study; recovery of the HSI in fasted fish was evident within three days of re-feeding. Liver protein content (expressed as % wet weight) was consistently depressed in the fasted fish in only one of the three studies. Liver total lipid content (expressed as % wet weight) was depressed in the fasted fish within two days of food deprivation. Because of the rapid and sustained decrease in the HSI of fasted fish, the hepatic total protein and lipid reserves, when considered on a body weight basis, were markedly lowered within the first few days of the fast. Plasma GH concentrations exhibited a bi-modal pattern of change, with a transient fall in levels, followed by a sustained increase in fasted fish. The indicators of interrenal activity were suggestive of a depressed pituitary-interrenal axis in fasted animals; plasma cortisol levels were elevated to levels of fed animals within one day of re-feeding. The indicators of thyroid hormone economy (plasma thyroid hormone levels, liver triiodothyronine content, hepatic 5-monodeiodinase (MD) activity, thyroid epithelial cell height) were similarly indicative of a depressed pituitary-thyroid axis in fasted animals, with recovery to levels of the fed animals within one week. Despite the compensatory changes in accumulation of reserves (as indicated by a compensatory increase in HSI), there were no apparent compensatory changes in any of the endocrine parameters evident during the re-feeding period. 相似文献
9.
Larval size heterogeneity is known to induce cannibalism, and procedures to avoid larval size differences are consequently implemented already during egg incubation and hatching. We investigated the relation between larval development variability, size heterogeneity and cannibalism in pikeperch. Larvae were sorted into five groups according to the time of hatching during a 65‐h period. The larvae with different times of hatch were then reared separately or together during an 18‐day period. Late hatched larvae were longer (P=0.003) and had less yolk remaining (P<0.001) than early hatched individuals at the time of hatching. However, on 11 days post fertilization, the late‐hatching larvae tended to have larger yolk reserves than earlier hatched individuals (P=0.07). Furthermore, the next day, a lower proportion in the late fraction had switched to exogenous feeding (P=0.024). That larvae with a late hatching time developed slower suggests a positive relationship between the hatching time and the embryonic developmental rate. However, differences in the length and available yolk reserves at hatching between larval fractions with different hatching times suggest that hatching is not strictly associated with a specific developmental stage, and that factors other than the development rate of the embryo are involved in the timing of hatching. 相似文献
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评《Ｆｒｅｓｈｗａｔｅｒ Ｆｉｓｈ Ｃｕｌｔｕｒｅ ｉｎ Ｃｈｉｎａ：Ｐｒｉｎｃｉｐｌｅｓ ａｎｄ Ｐｒａｃｔｉｃｅ》《ＦｒｅｓｈｗａｔｅｒＦｉｓｈＣｕｌｔｕｒｅＩｎＣｈｉｎａ：ＰｒｉｎｃｉｐｌｅｓａｎｄＰｒａｃｔｉｃｅ｝（中国淡水鱼类养殖原理与实践... 相似文献
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D. Saucier A.K. Julliard G. Monod H. de Bréchard L. Astic 《Fish physiology and biochemistry》1999,21(2):179-192
Cytochrome P4501A1 (CYP1A1) isoform, which is known as being of major toxicological significance, has been well-studied in the mammalian olfactory mucosa. Only few studies have dealt with this biotransformation system in the fish olfactory organ which is particularly vulnerable to waterborne xenobiotics since sensory neurons are in direct contact with the aquatic environment. The present immunocytochemical study describes the cellular and subcellular distributions of CYP1A1 in the olfactory organ of rainbow trout in both adults and embryos around hatching. The enzyme inducibility in response to a 4-day exposure to waterborne -naphthoflavone (0.1 mg l–1), a model inducer of CYP1A1, was also examined. In untreated adult fish, CYP1A1 was almost exclusively expressed in the nonsensory epithelium which covers the edges and the tip of the lamellae. Both goblet and ciliated nonsensory cells appeared immunoreactive. In -naphthoflavone-treated fish, in addition to a strong labeling in the nonsensory epithelium, ciliated nonsensory cells in the olfactory epithelium appeared well-labeled. Four days before hatching, only a few cells were weakly stained in the placodal epithelium of some embryos. By 7 days post-hatching, the enzyme expression was increased in the olfactory pit and it was restricted to ciliated nonsensory cells. No evident CYP1A1 induction was detected in either embryos or alevins. Results suggest the presence of a two-line CYP1A1 biotransformation system in the adult fish olfactory organ: a basal level of enzyme expression insured by the nonsensory epithelium and an additional line in which the sensory epithelium is activated in response to CYP1A1 inducers. This system might take place during development in parallel with the onset of the nonsensory epithelium. 相似文献
14.
Glutathione S-transferase (GST) isoenzymes were isolated from liver and kidney of carp (Cyprinus carpio) by glutathione affinity chromatography and chromatofocusing. Ten hepatic and eight renal catalytically active isoenzymes were identified. GST subunits from purified isoenzymes were further separated by high-performance liquid chromatography (HPLC) and were used as standards for the experimental sample analysis. Experimental samples came from carp that were fed fish meal (standard diet) or soybean bas ed diets for one year, injected or not with -naphthoflavone (BNF; i.p. injection of 50 mg kg-1). HPLC did not allow us to identify precisely the GST isoenzyme pattern in experimental carp. However, GSTs could be pooled in three categories: homodimeric, heterodimeric and unidentified GST subunits. On this basis, the effect of diet and BNF on the GST isoenzyme pattern was investigated. The homodimer/heterodimer ratio was decreased in liver of carp fed a standard diet and in kidney of both dietary groups. BNF increased the total specific GST activity in liver and kidney. However, the GST isoenzyme pattern was not modified in carp fed the standard diet while tissue specific modifications occured in carp fed the soybean diet. BNF decreased the homodimer/heterodimer ratio in liver and increased it in kidney. Abbreviations: BNF - -naphthoflavone; CDNB - 1-chloro-2,4-dinitrobenzene; GSH - reduced glutathione; GST - glutathione S-transferase; HPLC - high-performance liquid chromatography; SDS-PAGE - SDS-polyacrylamide gel electrophoresis. 相似文献
15.
Mathematical models in fish nutrition have proven indispensable in estimating growth and feed requirements. Nowadays, reducing the environmental footprint and improving product quality of fish culture operations are of increasing interest. This review starts by examining simple models applied to describe/predict fish growth profiles and progresses towards more comprehensive concepts based on bioenergetics and nutrient metabolism. Simple growth models often lack biological interpretation and overlook fundamental properties of fish (e.g. ectothermy, indeterminate growth). In addition, these models disregard possible variations in growth trajectory across life stages. Bioenergetic models have served to predict not only fish growth but also feed requirements and waste outputs from fish culture operations. However, bioenergetics is a concept based on energy-yielding equivalence of chemicals and has significant limitations. Nutrient-based models have been introduced into the fish nutrition literature over the last two decades and stand as a more biologically sound alternative to bioenergetic models. More mechanistic models are required to expand current understanding about growth targets and nutrient utilization for biomass gain. Finally, existing models need to be adapted further to address effectively concerns regarding sustainability, product quality and body traits. 相似文献
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The impact of 17-estradiol (E2) and the putative estrogenic compound, 4-nonylphenol (4-NP), on smoltification and vitellogenesis in Atlantic salmon (Salmo salar) was investigated during a 30 day period starting late April. Three groups of fresh water (FW) fish (1 year old, mixed sexes, average weight 23 g) were injected once a week with 50 µg (0.18 µmol) 17-estradiol, 3 mg (13.6 µmol) 4-nonylphenol dissolved in peanut oil, or peanut oil alone as control. Every ten days, subgroups were challenged with 28 ppt seawater (SW) for 24h, and sampled together with subgroups of FW fish. Treatment effects were examined on vitellogenic and osmoregulatory parameters. E2 and 4-NP treatment increased the total calcium and protein level in plasma and the hepatosomatic index of FW fish, both indicating an activated vitellogenesis in the liver. The presence of vitellogenin in the plasma of 4-NP- and E2-treated groups was further indicated by the appearance of a high molecular weight vitellogenin band (550 kDa) in electropherograms produced by native gel electrophoresis. This band appeared in exactly the same position in both the E2- and the 4-NP-treated groups but could not be detected in controls. During the 30 day treatment period, control fish approached the peak of smoltification, as indicated by a distinct silvery appearance, decreasing condition factor, increasing levels of gill Na+,K+-ATPase and improved hypoosmoregulatory performance in the SW-challenge test. Both E2 and 4-NP treatments significantly inhibited the progress of smoltification, as judged by a significant reduction of gill Na+,K+-ATPase activity, relative -subunit Na+,K+-ATPase mRNA expression, gill chloride cell density and a poorer hypoosmoregulatory performance of treated fish. The impaired SW-tolerance of E2- and 4-NP-treated fish was strongly correlated with a decreased gill Na+,K+-ATPase activity. Despite a difference in relative potency, the present study shows that 4-nonylphenol and 17-estradiol may have qualitatively similar inhibitory effects on smoltification and hypoosmoregulatory physiology of Atlantic salmon. Both 4-NP and E2 activated the vitellogenic system, and the study supports the hypothesis that sexual maturation and smoltification are antagonistic, developmental phenomena in salmon. It is suggested that the presence of estrogenic compounds in the environment may negatively influence smoltification and migration in wild stocks of salmon. 相似文献
18.
J. Antonio Martinez J. Carlos Seijo 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3-4):129-145
Abstract Reducing water exchange in shrimp aquaculture to minimize discharge of pollutants is a search for sustainability. In desert regions, like most of northwest Mexico, low water exchange must be complemented with artificial aeration to compensate for low levels of oxygen in warm and highly saline water. The economic yield of a low‐water‐exchange production system is compared against yield from a typical water‐exchange‐without‐aeration system for Penaeus vannamei culture. The difference between two systems is centered on pumping and aeration rates for a 100 ha semi‐intensive farm in northwest Mexico. A bioeconomic model was built to compare the systems. Risk analysis is adopted to account for uncertainty of seed price, shrimp growth rate, survival rate, and shrimp prices. The typical system was slightly more profitable than the low‐water‐exchange, aerated system. The latter used less electricity than the former in all of the three mortality‐rate scenarios. However, the difference in profitability is so small that for practical purposes both production systems provide similar economic yield. For a typical system, the probability of reaching a positive net present value (NPV) is high, therefore under the assumed risks, a 100 ha semi‐intensive shrimp farm in northwest Mexico is a good investment choice. 相似文献
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Lian Chuan Lim Andrew Soh Philippe Dhert Patrick Sorgeloos 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3-4):211-228
Abstract This paper describes a pilot culture system for the production of on‐grown Artemia in freshwater ornamental fish farms. The system had 21 culture units, each consisting essentially of three components: an oval‐shaped raceway, an air‐water lift system and two waste collectors. Using artificial seawater at 20 ppt for culture and at a mean production rate of 3 kg/m3 of water in a 12‐day cycle, the system had a production capacity of 8 metric tons of on‐grown Artemia a year. Biochemical analyses were preformed to evaluate the nutritional value of the on‐grown Artemia against three conventional live feeds, viz. live Artemia nauplii, live Moina and frozen bloodworms. Cost‐benefit analysis showed that with a capital investment of US$ 82,000 and an annual cost of production of US$ 81,000, the system achieved a high internal rate of return of 88% over a 10‐year period and a short payback period of 1.23 years. The availability of on‐grown Artemia would not only offer farmers and exporters a better alternative live food organism for feeding to their fish, but more importantly the possibility of enhancing the fish performance and quality through bioencapsulation. 相似文献