The synergistic interaction of thermal stress coupled with overstocking strongly modulates the transcriptomic activity and immune capacity of rainbow trout (Oncorhynchus mykiss)

The objective of the present study is to identify and evaluate informative indicators for the welfare of rainbow trout exposed to (A) a water temperature of 27 °C and (B) a stocking density of 100 kg/m3 combined with a temperature of 27 °C. The spleen-somatic and condition index, haematocrit and the concentrations of haemoglobin, plasma cortisol and glucose revealed non-significant differences between the two stress groups and the reference group 8 days after the onset of the experiments. The transcript abundance of almost 1,500 genes was modulated at least twofold in in the spleen of rainbow trout exposed to a critical temperature alone or a critical temperature combined with crowding as compared to the reference fish. The number of differentially expressed genes was four times higher in trout that were simultaneously challenged with high temperature and crowding, compared to trout challenged with high temperature alone. Based on these sets of differentially expressed genes, we identified unique and common tissue- and stress type-specific pathways. Furthermore, our subsequent immunologic analyses revealed reduced bactericidal and inflammatory activity and a significantly altered blood-cell composition in challenged versus non-challenged rainbow trout. Altogether, our data demonstrate that heat and overstocking exert synergistic effects on the rainbow trout’s physiology, especially on the immune system.publishedVersio

Altlastsanierung in der Bundesrepublik Deutschland im Spannungsfeld zwischen mikro- und makrooekonomischer Rationalitaet: Anforderungen an eine kosten-nutzen-orientierte Ordnungspolitik im Bereich von Genehmigungen fuer Reinigungsanlagen und Deponierungen

Available from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel A 193717 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Connecting the Members of Generation Y to Destination Brands: A Case Study of the CUBIS Project

There is direct correlation between building powerful destination brands and the degree to which tourists and locals share the brands values. The massive penetration of the active population by Generation Y has generated a major shift in tourism marketing, based on the profile of this cohort. The members of Generation Y are very different from previous generations. The so-called “digital natives” share high technological proficiency; they like to share their skills; they are disloyal consumers; and they are affected by trends. In order to connect with members of Generation Y and to actively involve them into the life of tourist destinations, viral, participative, interactive, networked and versatile marketing techniques should be employed. This article introduces the Intelligent Solution for Brand Culturalization (CUBIS) Project, which is a collaborative research initiative that offers to Destination Management Organizations an innovative idea of how to connect the members of Generation Y with destination brands using information and communication technologies (ICT). The CUBIS Project aims to create emotional attachment with the brand values and supports the adoption of the brand by young locals and tourists. The CUBIS idea is flexible and highly adaptable to other destinations. The article uses exploratory qualitative research in the form of a case study

Determination and Comparison of Physical Meat Quality Parameters of Percidae and Salmonidae in Aquaculture

Although aquaculture has been the fastest growing food sector for decades, there are no standardized parameters for most of the fish species regarding physical meat quality. Therefore, this study provides for the first time an overview of the physical meat characteristics of the most important fish species of the German Baltic Sea coast. Traditional farmed salmonids (rainbow trout (Oncorhynchus mykiss) and maraena whitefish (Coregonus maraena) as well as two percids (European perch, Perca fluviatilis and pikeperch, Sander lucioperca) were utilized for this comparison. The results demonstrate that the meat of the salmonids is very analogous. However, the post mortem degradation process starts faster in trout meat. In contrast, the meat quality characteristics of the percids are relatively different. The meat of pikeperch has comparatively low shear strength with a high water-holding capacity resulting in high meat tenderness. The opposite situation is present in European perch. The results indicate that it is not possible to establish the overall quality characteristics for fish or production form, as there is a high range of variability. Consequently, it is particularly important that meat quality characteristics are developed for important aquaculture species for further improvement through changes in husbandry conditions when necessary

FIGURE 4. A, B in Brittle stars (Echinodermata: Ophiuroidea) from the continental shelf off Angola and Namibia

FIGURE 4. A, B, Ophiactis plana; A, dorsal aspect; B, ventral aspect. C, D, Ophiopsila annulosa; C, dorsal aspect; D, ventral aspect. E, F, Ophiopsila guineensis; E, dorsal aspect; F, ventral aspect. Scale bars 1 mm

Nutrient Profile of Baltic Coastal Red Algae (<i>Delesseria sanguinea</i>), Baltic Blue Mussel (<i>Mytilus</i> spp.) and King Ragworm (<i>Alitta virens</i>) as Potential Feed Material in the Diet of Rainbow Trout (<i>Oncorhynchus mykiss</i> Walbaum, 1792): A Preliminary Assessment

The use of selected Baltic coastal organisms as potential alternative feed material in the formulation of rainbow trout diets was studied. German coastal water organisms (Delesseria sanguinea, seaweed red algae (A); Mytilus spp., Baltic blue mussel (M); Alitta virens, king ragworm (W)) were analyzed for nutrient, amino acid and mineral composition, and tested in comparative feeding trials. Five dietary treatments were supplied to a total of 165 juvenile rainbow trout (778 ± 111 g) for 75 days, allotted in 15 special brackish (3–5 practical salinity units (PSU)) water basins consisting of 11 fish each (3 fish tanks (300 L) at 12 °C per feeding group). The fish were fed as follows: C group, 100% basic diet (control); A group, 10% red algae in C diet; M group, 10% mussel in C diet; W group, 35% ragworm in C diet; AW group, 10% algae + 30% ragworm in C diet. Feed provision was performed manually, once a day, with the feed offer adjusted to 1.8% of fish weight for the respective tank. The fish weight gain (WG) and feed conversion ratio (FCR) were recorded. In the proximate analysis of the different coastal organisms, the lowest crude protein content in dry matter (DM) was found in blue mussels (10.9%), whereas it was almost doubled in algae (21.8%), with the highest being found in the ragworm (63.1%). By contrast, the crude ash content was the highest in the mussel (84.4%, mostly due to CaCO3 from the shell), much less in the red algae (28.1%) and the lowest in the ragworms (20.1%). The gross energy (GE) concentration was the highest in the ragworm (18.8 MJ × kg−1), 12.1 MJ × kg−1 in the algae and the lowest in the blue mussel (2.93 MJ × kg−1). The final weight of the fish ranged between 1780 and 2310 g at the end of the feeding trial, being the lowest for the fish fed the diet combined with red algae (A diet group) and the highest for the fish fed the control diet. No differences in FCR were found for the fish fed the five dietary treatments (p > 0.05), except for the W diet group (king ragworm has a lower FCR than that of the A group red algae, p < 0.05). The results from this trial suggest that at the tested amounts, both king ragworm and blue mussels are promising alternative feed material for rationing the rainbow trout diet, but not red algae, unless combined with ragworms

Stepping stones along urban coastlines-improving habitat connectivity for aquatic fauna with constructed floating wetlands

Urban development along coastlines is accompanied by habitat fragmentation and loss of habitat connectivity, particularly affecting the habitat and nursery function of estuarine areas for migratory marine species. Constructed floating wetlands, deployed as ‘stepping stones’ along urban coastlines where natural wetlands are missing, offer the potential to partially replace lost ecosystem services. Originally developed for wastewater treatment, constructed floating wetlands are now used to improve landscape aesthetics or create habitats for aquatic fauna and birds. This study presents a toolkit to identify appropriate sites for stepping stones using open source data and open source software alone. The toolkit was used to identify 85 potential installation sites along the German Baltic Sea coast, a large proportion of which are located in protected areas offering synergies with nature conservation measures. Though the sites are often located in protected areas, the field investigation revealed that natural vegetation is largely absent from the estuaries near urban areas. Constructed floating wetlands can never replace ‘core areas’ in ecological networks, but they can serve as stepping stones improving habitat connectivity, especially for diadromous fish species such as the threatened European eel. To ensure not only structural connectivity, but also functional connectivity, restoration efforts at the land-sea interface must be holistic and include adequate hydrologic connectivity

Gradual and Acute Temperature Rise Induces Crossing Endocrine, Metabolic, and Immunological Pathways in Maraena Whitefish (Coregonus maraena)

The complex and still poorly understood nature of thermoregulation in various fish species complicates the determination of the physiological status on the basis of diagnostic marker genes and indicative molecular pathways. The present study aimed to compare the physiological impacts of both gradual and acute temperature rise from 18 to 24°C on maraena whitefish in aquaculture. Microarray-based transcriptome profiles in the liver, spleen and kidney of heat-stressed maraena whitefish revealed the modulation of a significantly higher number of genes in those groups exposed to gradually rising temperatures compared with the acutely stressed groups, which might reflect early adaptation mechanisms. Moreover, we suggest a common set of 11 differentially expressed genes that indicate thermal stress induced by gradual or acute temperature rise in the three selected tissues. Besides the two pathways regulated in both data sets unfolded protein response and aldosterone signaling in epithelial cells, we identified unique tissue- and stress type-specific pathways reflecting the crossroads between signal transduction, metabolic and immunologic pathways to cope with thermal stress. In addition, comparing lists of differentially regulated genes with meta-analyzed published data sets revealed that “acute temperature rise”-responding genes that encode members of the HSP70, HSP90, and HSP40 families; their functional homologs; co-chaperones and stress-signal transducers are well-conserved across different species, tissues and/or cell types and experimental approaches