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Crangon crangon is economically a very important species. Recently, promising culture attempts have been made, but a major problem is the uncontrollable mortality during the grow-out phase. As of yet, the life cycle of C. crangon is not closed in captivity so wild-caught individuals are used for further rearing. Therefore, it is important to investigate the virome of C. crangon both in wild-caught animals as in cultured animals. In recent years, next-generation-sequencing (NGS) technologies have been very important in the unravelling of the virome of a wide range of environments and matrices, such as soil, sea, potable water, but also of a wide range of animal species. This will be the first report of a virome study in C. crangon using NGS in combination with the NetoVIR protocol. The near complete genomes of 16 novel viruses were described, most of which were rather distantly related to unclassified viruses or viruses belonging to the Picornavirales, Bunyavirales Nudiviridae, Parvoviridae, Flaviviridae, Hepeviridae, Tombusviridae, Narnaviridae, Nodaviridae, Sobemovirus. A difference in virome composition was observed between muscle and hepatopancreatic tissue, suggesting a distinct tissue tropism of several of these viruses. Some differences in the viral composition were noted between the cultured and wild shrimp, which could indicate that in sub-optimal aquaculture conditions some viruses become more abundant. This research showed that a plethora of unknown viruses is present in C. crangon and that more research is needed to determine which virus is potentially dangerous for the culture of C. crangon.

Current coastal protection measures become increasingly insufficient under circumstances of climate change and increasing anthropogenic pressures. Aggregations of the ecosystem engineer Lanice conc...

The field-to-fork concept comprises opportunities for providing consumers with nutritious and health-beneficial food in order to meet the growing interest in health-beneficial foods and to countera...

Multiple enveloped viruses with rod-shaped nucleocapsids have been described, infecting the epithelial cell nuclei within the hepatopancreas tubules of crustaceans. These bacilliform viruses share the ultrastructural characteristics of nudiviruses, a specific clade of viruses infecting arthropods. Using histology, electron microscopy and high throughput sequencing, we characterise two further bacilliform viruses from aquatic hosts, the brown shrimp (Crangon crangon) and the European shore crab (Carcinus maenas). We assembled the full double stranded, circular DNA genome sequences of these viruses (~113 and 132 kbp, respectively). Comparative genomics and phylogenetic analyses confirm that both belong within the family Nudiviridae but in separate clades representing nudiviruses found in freshwater and marine environments. We show that the three thymidine kinase (tk) genes present in all sequenced nudivirus genomes, thus far, were absent in the Crangon crangon nudivirus, suggesting there are twenty-eight core genes shared by all nudiviruses. Furthermore, the phylogenetic data no longer support the subdivision of the family Nudiviridae into four genera (Alphanudivirus to Deltanudivirus), as recently adopted by the International Committee on Taxonomy of Viruses (ICTV), but rather shows two main branches of the family that are further subdivided. Our data support a recent proposal to create two subfamilies within the family Nudiviridae, each subdivided into several genera.

The European brown shrimp, Crangon crangon, is a highly valued commercial species in Europe. These shrimp fisheries are characterized by strong seasonal variations in average landings. Attempts to 'catch and hold' wild adults in land-based rearing systems have been proven to be very difficult, due to inadequate feed, slow growth and high mortality. In this study, we have optimized design and operation procedures of a small-scale static larval rearing system for the culture of C. crangon larvae. Focus was on optimizing larval survival via water temperature, feed selection, feeding regime and density. This is the first report that shows that C. crangon larvae can be reared at high densities of 300 larvae L-1 with high survival of 73.5 (+/- 5.4)% under laboratory conditions. In these systems, larvae can be fed exclusively Artemia nauplii according to a feeding regime which is adjusted based on major moulting events. Addition of microalgae may further increase survival by 10%. The information gathered during this research can be applied to further optimize larval development in either flow-through or recirculation systems.

The European Blue Growth perspective suggests a larger share in global economic productionand food security appointed to the marine and coastal zone and an increase of marine and coastalinfrastructures and operations. However, this growth must be aligned with increasingenvironmental constraints as well as complying and restoring regulations and frameworks. Thecompliance of growth and sustainability requires the adoption of economically and ecologicallyefficient behaviours, based on a wider incorporation of available information and knowledge fromthe industry and citizens alike. Marine and coastal managers must make decisions to maintainthe social, economic, and ecological health of marine and coastal areas while operating, planningand managing their activities at sea.The European funded FORCOAST project represents a step forward in this direction by bringingthe coastal water quality and met-ocean information closer to the target sectors: wild fisheries,oyster grounds restoration, and bivalve mariculture. FORCOAST will develop, test anddemonstrate, in operational mode, novel Copernicus-based downstream information services thatwill incorporate and combine Copernicus Marine Environment Monitoring Service (CMEMS),Copernicus Land Monitoring Service (CLMS) and Climate Change Monitoring Service (CMS),local monitoring data and advanced modelling in the service.FORCOAST will provide consistent high-resolution data products for coastal applications, basedon a standardized data processing scheme. The services of FORCOAST will provide managerialtools (e.g decision support, user warnings, on-demand case study) built upon those products andimplemented through cloud-processing infrastructures.FORCOAST will develop and provide those services in eight pilot service uptake sites coveringfive different regional waters (North Sea, Baltic Sea, Mediterranean Sea, Black Sea and thecoastal Atlantic Ocean). Each of those pilots gathers marine information producers (eg. models),providers (dissemination) and user (operating SMEs), to ensure inter-sectoral consistency.The outcome of FORCOAST is a novel commercial service that will provide Copernicus-baseddownstream information coastal services to a variety of stakeholders, which will result in anoperation, planning and management improvement of different marine activities in the sectors ofwild fisheries and aquaculture, having an economic and societal positive effect on the involvedparties.*This project has received funding from the European Union’s Horizon 2020 research and innovationprogramme under grant agreement No 870465

Despite electric pulse fishing being regarded as a promising environmentally friendly fishing method, very little is known about possible negative effects on early life stages of bottom-dwelling species such as Sole Solea solea. Electrotrawling for brown shrimp Crangon crangon is increasingly used in shallow coastal zones and estuaries of the southern North Sea. As these fishing grounds are often important nurseries and spawning areas for various marine species, electrotrawling could therefore harm inhabiting fishes during their early life stages. Hence, this research aims to investigate the effect of electric pulses used to catch brown shrimp on the survival and development of Sole embryos and larvae. Exposure of Sole embryos at 2d postfertilization and larvae at 11d posthatching to pulsed DC used to catch brown shrimp did not result in a lower survival 8d after exposure. Additionally, no differences in yolk sac resorption and morphometric length measurements of the notochord, muscle, eye, and head were observed in the developing larvae.

Crangon crangon bacilliform virus (CcBV) was first discovered in 2004 in European brown shrimp (Crangon crangon) caught along the English coast. This study describes a duplex PCR assay developed for the detection of CcBV, based on amplification of the lef-8 gene (211 bp) of CcBV and the E75 gene (105 bp) of C. crangon as an internal amplification control. The lef-8 and E75 primer pairs were designed based on preliminary genome sequencing information of the virus and transcriptomic data available for C. crangon, respectively. Sequencing of the resulting amplicons confirmed the specificity of this PCR assay and sequence analysis of the lef-8 fragment revealed amino acid identity percentages ranging between 31 and 42% with members of the Nudiviridae, proposing that CcBV may reside within this family. Finally, the duplex PCR assay was applied to samples of C. crangon hepatopancreas tissue collected along the Belgian coast to screen for the presence of CcBV. The prevalence of CcBV averaged 87%, which is comparable to previous reports of high prevalence, based upon histological analysis, in shrimp collected along the English coast. Development of a specific and sensitive PCR assay to detect CcBV will provide a useful tool for future aquaculture and research programs involving C. crangon.

The European brown shrimp, Crangon crangon, is a highly valued commercial species fished in the north-eastern Atlantic, especially the North Sea. The shrimp fisheries are mainly coastal and exert high pressures on the local ecosystems, including estuaries. The culture of the species provides an alternative to supply a niche market (large live/fresh shrimps) in a sustainable manner. However, after more than a century of biological research on this species, there is still little knowledge on its optimal rearing conditions. C. crangon remains a difficult species to keep alive and healthy for an extended period of time in captivity. This review is based on a comprehensive literature search and reflects on the current status of experimental rearing techniques used for this species, identifies the problems that compromise the closing of the life cycle in captivity and provides examples on how these problem issues were solved in the culture of commercial shrimp species or other crustaceans. The ability to consistently produce high-quality offspring could initiate the commercial production of this valuable shrimp. A further advantage of the ability to consistently produce high-quality offspring of this species would facilitate research on the development of new bioassays with this ecologically and economically important species in a wide variety of biochemical and physiological studies.

Many zooplanktonic organisms, like the cyclic parthenogenetic rotifer Brachionus plicatilis (Rotifera: Monogononta), are actually a complex of species and biotypes with a high degree of morphological similarity (i.e. cryptic species). Various phylogenetic studies with molecular markers (e.g. ITS1 and COI) on wild Brachionus populations described the presence of at least nine genetically divergent Brachionus species and biotypes. Because different studies found evidence that these cryptic species and biotypes differ significantly in ecological preferences and thus probably behave differently in response to rearing conditions in the hatchery, questions rise on the actual identity of the rotifer strains used in aquaculture, where Brachionus discrimination is still based on morphology. This study is a part of an investigation of the genetic make-up of strains used in hatcheries, aquaculture research institutes and laboratories, and describes the rapid and sensitive PCR–DGGE method for the detection of Brachionus species and biotypes based on nucleotide sequence variation within the mitochondrial 16S rRNA gene. Considerable genetic diversity was found, albeit smaller within hatcheries than within laboratories and aquaculture research institutes. All 16S haplotypes produced an unambiguous DGGE fingerprint out of which a database was constructed.

The decapod Crangon crangon is one of the most valuable European fisheries commodities. Despite its economic importance, little sequence data is available for this shrimp species. In this paper, we report the transcriptome sequencing for five different stages of C. crangon (early embryo, late embryo, larva, female adults and male adults) and the annotation and stage-specific expression analysis of nuclear receptors (NRs) and RNA interference (RNAi)-related genes. The NRs are transcription factors that play an essential role in growth, development, cell differentiation, molting/metamorphosis and reproduction, while the RNAi-related genes are very important for internal gene expression regulation and in antiviral defense. We discovered a NR in the female C. crangon which is either a very rapidly evolved homolog of HR10, or a novel NR altogether. This new NR could act as a biological marker for sex determination as it is not expressed in male adults. Most RNAi-related genes were present in C. crangon, proving that the requirements for successful RNAi is present in this decapod shrimp. RNAi-based applications in Crangon such as its use in functional genomics or as antiviral therapeutics could become very important in the near future.

pouting; acoustic telemetry; dummy transmitter; survival rate