L'estrès en els peixos : tipus, efectes i paràmetres de mesura

The relevance of stressing procedures and their measurement is emphasized. Types of and responses to stress are presented. After several experiments regarding stressing procedures as grading and hauling, crowding and parasite infection, changes are detected at the levels of primary responses (increase of plasma cortisol), secondary (respiratory, hematological and metabolic alterations) and tertiary responses (decrease of activity and growth).Es destaca la importància de l'estrès en els peixos i el seu mesurament. Després d'indicar les modalitats d'estrès, es descriuen els tipus de respostes. En diferents experiments on s'estudiaven procediments estressants com la classificació i el transport, l'apinyament o la infecció parasitària, es detecten respostes primàries (augment del cortisol plasmàtic), secundàries (alteracions respiratòries, hematològiques i metabòliques) i terciaries (disminució de l'activitat i el creixement)

Stocking density and growth performance of Senegalese sole (Solea senegalensis). Preliminary results

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Stocking density and its influence on shape of Senegalese sole adults

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Pérdida de variabilidad genética en una población de cultivo de lenguado senegalés (Solea senegalensis) revelada mediante datos de secuencia de la región control del ADN mitocondrial y de marcadores microsatélite

Comparisons of the levels of genetic variation within and between a hatchery F1 (FAR, n=116) of Senegalese sole, Solea senegalensis, and its wild donor population (ATL, n = 26), both native to the SW Atlantic coast of the Iberian peninsula, as well as between the wild donor population and a wild western Mediterranean sample (MED, n=18), were carried out by characterizing 412 base pairs of the nucleotide sequence of the mitochondrial DNA control region I, and six polymorphic microsatellite loci. FAR showed a substantial loss of genetic variability (haplotypic diversity, h=0.49±0.066; nucleotide diversity, π=0.006±0.004; private allelic richness, pAg=0.28) to its donor population ATL (h=0.69±0.114; π=0.009±0.006; pAg=1.21). Pairwise FST values of microsatellite data were highly significant (P < 0.0001) between FAR and ATL (0.053) and FAR and MED (0.055). The comparison of wild samples revealed higher values of genetic variability in MED than in ATL, but only with mtDNA CR-I sequence data (h=0.948±0.033; π=0.030±0.016). However, pairwise ΦST and FST values between ATL and MED were highly significant (P < 0.0001) with mtDNA CR-I (0.228) and with microsatellite data (0.095), respectively. While loss of genetic variability in FAR could be associated with the sampling error when the broodstock was established, the results of parental and sibship inference suggest that most of these losses can be attributed to a high variance in reproductive success among members of the broodstock, particularly among females.Se compararon los niveles de variabilidad genética de la F1 de una población de cultivo (FAR, n=116) de lenguado senegalés, Solea senegalensis, y de una muestra de su población de origen (ATL, n=26), ambas provenientes del SO de la península ibérica (Atlántico), así como entre esta última y una muestra de individuos salvajes del Mediterráneo occidental (MED, n=18), mediante la caracterización de una secuencia de 412 pares de bases de la Región Control-I del ADN mitocondrial, y de seis loci microsatélite. FAR experimentó una reducción sustancial de variabilidad genética (diversidad haplotípica, h=0.49±0.066; diversidad nucleotídica, π=0.006±0.004; riqueza de alelos privados, pAg=0.28) respecto a su población original ATL (h=0.69±0.114; p=0.009±0.006; pAg=1.21). Los valores de FST entre poblaciones, calculados a partir del análisis de los microsatélites, fueron altamente significativos (p < 0.0001) para FAR y ATL (0.053), y para FAR y MED (0.055). La comparación de las dos muestras salvajes mostró mayores niveles de variabilidad genética en MED que en ATL, pero únicamente en marcadores mitocondriales (h=0.948±0.033; π=0.030±0.016). Sin embargo, los valores de e ΦST y FST presentaron diferencias significativas (p < 0.0001) respectivamente tanto a partir de datos mitocondriales (0.228) como de microsatélites (0.095), aunque la pérdida de variabilidad en FAR podría estar asociada al error de muestreo al establecer el lote de reproductores a partir de peces salvajes, los resultados de la inferencia de parentesco sugieren que la mayor parte de esta pérdida podría estar relacionada con la varianza reproductiva entre los miembros de la generación parental, particularmente entre las hembras

Mitochondrial control region and microsatellite data show low genetic variability in reared senegalese sole, Solea senegalensis. Preliminary data

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Swimming behaviour patterns of Carassius auratus and Solea senegalensis at different velocities

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Técnica de biopsia muscular con aguja cortante fina en peces

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Aquaculture perceptions in the Barcelona metropolitan area from fish and seafood wholesalers, fishmongers, and consumers

Aquaculture provides more than half of the global seafood production and offers a wide diversity of high-quality products. However, its social acceptability is still not well established. The goal of this study was to determine the perceptions of aquaculture by different stakeholders along the seafood value chain in the Barcelona metropolitan area. The methodology used was based on a two-phase qualitative approach: the nominal group technique (NGT) and the Delphi survey. In the NGT phase, three groups, wholesalers, fishmongers and consumers, the latter divided into two subgroups according to the frequency of consumption of seafood, were used to collect and rank positive and negative perceptions about aquaculture. This information was subsequently used to build the questionnaire for the Delphi survey, which involved a group of experts from the board of the Wholesalers' Association, Fishmongers' Guild board and consumers' associations. Results showed that among the different stakeholders the highest concordance in positive aspects of aquaculture products included market issues and the stable quality of farmed products. On the other hand, the highest concordance in negative aspects included the lack of sufficient information about aquaculture, which was a serious issue for all stakeholders, and quality. Globally, animal welfare and environmental impact issues were not of much concern, although they included some minor positive and negative perceptions. The diversity of opinions among experts on certain aspects further emphasizes the need for more information, as they could have a potential role as information prescribers to consumers. We argue that information campaigns can take advantage of the positive perception of market issues (convenience, price, diversity) and quality stability to create a favourable predisposition towards aquaculture and thus help to introduce other problems in which perceptions generate a stronger debate. In communication or marketing campaigns, it is essential to highlight the quality and safety of farmed products, with a particular emphasis on the quality of fish feed as a guarantee of optimal nutritional and organoleptic properties of aquaculture products. Welfare and environment generate minor negative perceptions, so they should appear in campaigns, with a firm focus on the sustainability of the aquaculture sector, to improve its general image. In summary, the results of this study contribute to identifying the most relevant aspects to be taken into account to improve the public perception of aquaculture in the Barcelona area and may be of help in the design of similar efforts elsewhere.Postprint (updated version

From myths to reality: how to communicate aquaculture

L&rsquo;aq&uuml;icultura &eacute;s un sector complex i divers, que avui aporta el 53 % dels productes pesquers d&rsquo;&uacute;s alimentari al m&oacute;n. El sector ha fet un esfor&ccedil; per desenvolupar una aq&uuml;icultura sostenible i responsable que no sempre s&rsquo;ha sabut explicar. Ind&uacute;stria, acad&egrave;mia i Administraci&oacute; sovint han partit d&rsquo;una visi&oacute; a la defensiva. Davant d&rsquo;una decisi&oacute; de compra, els consumidors tenen dificultats per comprendre el que el producte d&rsquo;aq&uuml;icultura aporta en termes de qualitat, impacte ambiental o benestar animal. La percepci&oacute; de manca d&rsquo;informaci&oacute; per part dels consumidors s&rsquo;ha considerat un coll d&rsquo;ampolla per al ple desenvolupament del sector. Les fonts d&rsquo;informaci&oacute; que utilitzen els consumidors (minoristes, certificacions, premsa) no han ajudat a millorar la seva percepci&oacute;. Es proposa partir d&rsquo;una visi&oacute; positiva que emfatitzi els avantatges per als consumidors (qualitat, tra&ccedil;abilitat, sostenibilitat).Paraules clau: aq&uuml;icultura, percepci&oacute;, consumidors, comunicaci&oacute;, sostenibilitat.Aquaculture is a complex and diverse sector which now accounts for 53 % of the world&rsquo;s fish food products. An improvement effort has been made to develop a sustainable and responsible aquaculture, an effort which has not always been correctly presented. Industry, academia and administration have often adopted a defensive attitude. When making a purchase decision, consumers find it hard to understand what an aquaculture product offers in terms of quality, environmental impact or animal welfare. The perception of a lack of information on the part of consumers has been considered a bottleneck for the full development of the sector. The information sources used by consumers (retailers, certifications, press) have not helped to improve this perception. As a starting point, this paper recommends a positive vision that emphasizes aquaculture&rsquo;s benefits for the consumer (quality, traceability, sustainability).Keywords: aquaculture; perception; consumers; communication; sustainability