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María José Sánchez-Muros Salvador Villacreces Genaro Miranda-de la Lama Carolina de Haro Fernando García-Barroso 《Fish physiology and biochemistry》2013,39(3):581-591
This work investigates the changes in the morphological traits, body composition, body fat and oxidative stress of Sparus aurata under two stress conditions: a low weekly exposure to the pesticide Diuron and chronic handling stress. The fish exposed to handling stress showed lower values in the morphological traits and perivisceral fat, whereas chemical stress induced a decrease in the percentage of muscle and carcase and an increase in the percentage of spleen and hepatosomatic index. The two stress situations produced changes in the FRAP (ferric reducing antioxidant power) levels in all organs studied with a particularly marked response for Diuron in the gill. No significant differences in the ROS (reactive oxygen species) level were found for the digestive tract or the gill. In muscle, only Diuron produced a significant increase in ROS, while in liver, both treatments increased the ROS levels. This supports the oxidative stress sensitivity to chemical stress and shows that also could be an appropriate indicator of handling stress. The morphological indexes and body components examined could be practical and easy welfare indicators. Nevertheless, further works must be needed to use under the production conditions in fish farms. 相似文献
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Formulation of an Alternative Culture Medium for Arthrospira maxima (Spirulina) Based on “Tequesquite,” a Traditional Mineral Resource 下载免费PDF全文
Fernando Martínez‐Jerónimo Dante Ivo Flores‐Hernández Juvencio Galindez‐Mayer 《Journal of the World Aquaculture Society》2017,48(6):887-897
Culture media formulation for Arthrospira maxima (formerly designated as Spirulina maxima) production is a constraining factor. Use of synthetic media could be expensive because most of the commercial strains require salinity conditions higher than 20 g/L. In this study, a traditional, pre‐Hispanic mineral resource, known as “tequesquite,” was used as the base for the formulation of an alternative and low‐cost culture medium. Tequesquite is available from outcrop areas located in the basin of the former Lake Texcoco, where A. maxima thrived in pre‐Hispanic times. The effect on the biomass production of different tequesquite‐based formulations, varying N, P, and , was tested and compared with results obtained with Zarrouk's medium (ZM). Growth of biomass in some alternative formulations showed no significant differences compared with ZM. Production in a bubble‐column photobioreactor of the alternative medium reached a maximum of X = 2570.4 mg/L dry weight, compared with X = 2931.4 mg/L dry weight obtained with ZM. The proposed tequesquite‐medium formulation has equivalent N and P concentrations as ZM, but only 50% of NaHCO3, thus reducing the medium's cost. In addition, it avoids the use of seawater or NaCl to provide the salinity condition required for the adequate growth of Arthrospira. 相似文献
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Fernando M Pelicice Valter M Azevedo‐Santos Jean R S Vitule Mário L Orsi Dilermando P Lima Junior André L B Magalhães Paulo S Pompeu Miguel Petrere Jr Angelo A Agostinho 《Fish and Fisheries》2017,18(6):1119-1133
Neotropical freshwater fishes are the most diverse on the planet (>5,500 species), although nations in Latin America have been negligent regarding their conservation. National policies have historically encouraged unsustainable practices, and recent decades have witnessed a sharp increase in harmful activities. Our aim with this review was to expose this situation and illustrate how national policies constitute the main threat to freshwater fish biodiversity. We explain that the most devastating, pervasive and systemic threats are rooted in official policies, particularly unsustainable activities (e.g. hydropower, water diversion, mining, aquaculture, agriculture and fishing), poor management/conservation (e.g. fish stocking and passages) and harmful legislation (e.g. poor licensing, non‐native species). We provide a broad portrait of the Neotropical scenario, where unsustainable policies have caused considerable damage to freshwater ecosystems, and focus on major examples from Brazil, where development projects have caused large‐scale losses to fish biodiversity. Such modus operandi of human development is incompatible with the persistence of biodiversity, and no simple solution is available to correct or minimize its effects. The current situation demands a profound behavioural shift towards better practices and policies, or these multiple high‐impact activities will continue eroding freshwater fish biodiversity and impairing essential ecosystem services. 相似文献
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Mónica B. Betancor Aurelio Ortega Fernando de la Gándara Douglas R. Tocher Gabriel Mourente 《Fish physiology and biochemistry》2017,43(2):493-516
The present study is the first to evaluate lipid metabolism in first-feeding Atlantic bluefin tuna (ABT; Thunnus thynnus L.) larvae fed different live prey including enriched rotifers Brachionus plicatilis and Acartia sp. copepod nauplii from 2 days after hatch. Understanding the molecular basis of lipid metabolism and regulation in ABT will provide insights to optimize diet formulations for this high-value species new to aquaculture. To this end, we investigated the effect of dietary lipid on whole larvae lipid class and fatty acid compositions and the expression of key genes involved in lipid metabolism in first feeding ABT larvae fed different live prey. Additionally, the expression of lipid metabolism genes in tissues of adult broodstock ABT was evaluated. Growth and survival data indicated that copepods were the best live prey for first feeding ABT and that differences in growth performance and lipid metabolism observed between larvae from different year classes could be a consequence of broodstock nutrition. In addition, expression patterns of lipid metabolic genes observed in ABT larvae in the trials could reflect differences in lipid class and fatty acid compositions of the live prey. The lipid nutritional requirements, including essential fatty acid requirements of larval ABT during the early feeding stages, are unknown, and the present study represents a first step in addressing these highly relevant issues. However, further studies are required to determine nutritional requirements and understand lipid metabolism during development of ABT larvae and to apply the knowledge to the commercial culture of this iconic species. 相似文献
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