44 research outputs found
An assessment of health management and biosecurity procedures in marine fish farming in Spain
Marine fish farming in Spain has experienced problems of performance due to losses caused by infectious diseases. Biosecurity and health management are identified by the Food and Agriculture Organization (FAO) as current priorities for proper aquaculture governance. However, they both transcend the responsibility of farmers and require significant resources, concerted action and cooperation. This study presents the analysis of biosecurity practices on marine fish farms, through a questionnaire-based survey on biosecurity procedures and an analysis of health management practices for different stakeholders. The Strengths, Weaknesses, Opportunities, and Threats (SWOT) technique was implemented, which identified the important threats and weaknesses faced by the sector, such as the risk of direct disease transmission between farms, the high likelihood of importing diseases through juvenile shipments, the chronic lack of communication between stakeholders, and the deficient coordination of health strategies. Strengths included awareness of prevention measures and the availability of expertize of health experts at most levels. On the other hand, the availability of experts together with the need to adapt governance to the current production systems were seen as opportunities. Health management measures themselves were actually already found to be adapted to the type of production but they varied between companies (i.e. categorization and diagnosis of mortalities). Nevertheless, the quality of expertize along the value chain provided by private and public laboratories, research institutes, Health Protection Groups, companies and veterinarians was noteworthy. However, there was still a need for all stakeholders involved in marine fish health to improve diagnostics, provide epidemiological information, biosecurity and prevention measures, as well as to promote transparency for better health governance
Survey on laboratories and consultants working in the diagnostics of European seabass and gilthead seabream diseases: preliminary results
European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) are prevailing species in
Mediterranean marine finfish aquaculture, and despite an increasing demand of the global markets for
high-quality seafood, production and technical performance of these two species in the EU has stagnated
over the last few years. Two EU Horizon 2020 projects, MedAID and PerformFISH were launched in
2017 to increase the competitiveness and sustainability of the Mediterranean marine fish aquaculture
sector. Since the impact of diseases has been one of the factors attributed to the stagnation, both projects
envisaged that the concept of healthy fish was a prerequisite for sustainable and profitable aquaculture.
A key element of disease surveillance and health management is the availability of fast, reliable, efficient
and validated diagnostic techniques capable of detecting the presence of pathogens and timely diagnosis
of diseases in fish stocks. Collaborative activities between both consortia launched specific activities to
identify all actors involved in diagnostics and to evaluate their diagnostic capacities. An online “Questionnaire on diagnostic capacities in the Mediterranean basin” was carried out. The results obtained showed
disproportionate diagnostic capacity between European and non-European Mediterranean countries.
European countries in general showed a high level of diagnostic capacity with many advanced or specialised labs dealing with the main diseases of concern for sea bass and sea bream. There was evidence of
lower diagnostic capacities in non-European Mediterranean countries in contrast with their high degree
of production, which poses a significant regional risk considering the important movement of juveniles
in the region. These findings indicate the necessity to address the health management in the region in a
more holistic, cooperative and harmonised way. An important finding was a lack of capacity to diagnose
viral diseases although VNN has been identified to be the main health threat.Efforts should be engaged in
capacity building in the countries missing particular techniques and improvement and training is a priorty.
For this purpose, national focal points should be established to create an international network aimed at
improving and harmonising all future activities in the field of diagnostics of Mediterranean fish diseases.info:eu-repo/semantics/publishedVersio
Fish Farms at Sea: The Ground Truth from Google Earth
In the face of global overfishing of wild-caught seafood, ocean fish farming has augmented the supply of fresh fish to western markets and become one of the fastest growing global industries. Accurate reporting of quantities of wild-caught fish has been problematic and we questioned whether similar discrepancies in data exist in statistics for farmed fish production. In the Mediterranean Sea, ocean fish farming is prevalent and stationary cages can be seen off the coasts of 16 countries using satellite imagery available through Google Earth. Using this tool, we demonstrate here that a few trained scientists now have the capacity to ground truth farmed fish production data reported by the Mediterranean countries. With Google Earth, we could examine 91% of the Mediterranean coast and count 248 tuna cages (circular cages >40 m diameter) and 20,976 other fish cages within 10 km offshore, the majority of which were off Greece (49%) and Turkey (31%). Combining satellite imagery with assumptions about cage volume, fish density, harvest rates, and seasonal capacity, we make a conservative approximation of ocean-farmed finfish production for 16 Mediterranean countries. Our overall estimate of 225,736 t of farmed finfish (not including tuna) in the Mediterranean Sea in 2006 is only slightly more than the United Nations Food and Agriculture Organization reports. The results demonstrate the reliability of recent FAO farmed fish production statistics for the Mediterranean as well as the promise of Google Earth to collect and ground truth data
Genetic Resistance to Rhabdovirus Infection in Teleost Fish Is Paralleled to the Derived Cell Resistance Status
Genetic factors of resistance and predisposition to viral diseases explain a significant part of the clinical variability observed within host populations. Predisposition to viral diseases has been associated to MHC haplotypes and T cell immunity, but a growing repertoire of innate/intrinsic factors are implicated in the genetic determinism of the host susceptibility to viruses. In a long-term study of the genetics of host resistance to fish rhabdoviruses, we produced a collection of double-haploid rainbow trout clones showing a wide range of susceptibility to Viral Hemorrhagic Septicemia Virus (VHSV) waterborne infection. The susceptibility of fibroblastic cell lines derived from these clonal fish was fully consistent with the susceptibility of the parental fish clones. The mechanisms determining the host resistance therefore did not associate with specific host immunity, but rather with innate or intrinsic factors. One cell line was resistant to rhabdovirus infection due to the combination of an early interferon IFN induction - that was not observed in the susceptible cells - and of yet unknown factors that hamper the first steps of the viral cycle. The implication of IFN was well consistent with the wide range of resistance of this genetic background to VSHV and IHNV, to the birnavirus IPNV and the orthomyxovirus ISAV. Another cell line was even more refractory to the VHSV infection through different antiviral mechanisms. This collection of clonal fish and isogenic cell lines provides an interesting model to analyze the relative contribution of antiviral pathways to the resistance to different viruses
In vitro studies and in vivo immunisation with the first viral haemorrhagic septicaemia viruses isolated in Spain compared to international reference serotypes
The first five viral haemorrhagic septicaemia virus (VHSV) isolates found in Spain were examined for in vitro growth characteristics, neutralisation by trout antiserum and immunisation challenge of trout fingerlings by water immersion. The viruses had come from different host species in various geographical locations in different years. Three reference VHSV serotypes (F1, F2 and 23·75) were also included in the study. There appeared to be little relationship between the in vivo delay of mortality or the protection of the immunised trout after challenge and the in vitro characteristics studied. In contrast to the in vitro results, the in vivo delay of mortality suggested a closer relationship of the Spanish VHSV isolates to the F2 serotype than to the F1 or the 23·75 serotypes. If the final protection figures are analysed, however, there could be three or four groups of viruses. © 1992
An ISS-XPS study on the oxidation of Al(111); identification of stoichiometric and reduced oxide surfaces
Revista de psicodidáctica
Resumen y palabras clave en español y en inglésResumen basado en el de la publicaciónSe describe brevemente la experiencia realizada por un equipo de investigación cooperativa, en torno al proceso de diseño globalizado, desarrollo y evaluación de las líneas transversales en el área de Lengua, siguiendo la
metodología de la investigación acción. Después de una rápida justificación de la
selección del tema y metodología de investigación utilizados, se contemplan las fases
y procedimientos de recogida y análisis de la información empleados. Finalmente
se avanzan algunas de las conclusiones extraidas de esta experiencia, en relación a
la conceptualización y diseño de las líneas transversales, así como a las posibilidades de la investigación acción como modelo de formación del profesorado para su
mejor desarrollo profesional.ES
Stimulation of adherent cells by addition of purified proteins of viral hemorrhagic septicemia virus to trout kidney cell cultures
Purified proteins of the virus causing viral hemorrhagic septicemia in the trout were added to cultures on semisolid medium of leukocytes obtained from either healthy or immunized rainbow trout. Adherent cells were specifically stimulated by the glycoprotein of the viral spikes and, to a lesser extent, by the nucleoproteins. In contrast, a specific memory response was associated more with the nucleoproteins than with the glycoprotein when leukocytes from trout immunized with the virus were employed. These results suggest the necessity of employing both proteins in subunit vaccination trials and the possibility of using this assay to select the proper epitopes for genetically engineered proteins during subunit vaccine development