The carp farmers of today face many challenges, with changing consumer habits, drought, losses of fish to avian predators and diseases presenting some of the most widespread threats. Our study has selected two European carp-farming areas as case studies: the Aischgrund in Germany and the Barycz Valley in Poland, where local stakeholders have initiated region-marketing concepts. The carp provides the core identity of these region-marketing. The region-marketing aims to boost touristic attractiveness of the regions and should indirectly support carp farmers in the strained economic situation for carp aquaculture. Notwithstanding, it is unknown, how the region-marketing effects carp farms' economics. Stakeholders were interviewed to explore the establishment and the essence of these region-marketing concepts. Focus groups of carp farmers have informed our sample of representative farms. The representative farm models enabled to compare the costs and profitability of different carp enterprises. Further, the farm models helped to explore the potential impacts and efficacy of region-marketing initiatives introduced in recent years. Our results show that the single grow-out and traditional sale of conventional fresh carp is scarcely profitable. Farmers in both regions struggle with limited options for adaptation or diversification. The difficulties are most pronounced for small-scale peasant carp farms. We consider the potential of labelling as part of region-marketing and future transfer payments that honor the contribution of carp farming to ecosystem services and cultural value (region's identity). In particular for larger-scaled carp farms, region-marketing seems to be a good means of enhancing direct marketing opportunities and generating new income sources via diversification. Highlights► The study examines the profitability of carp farms in Polish Barycz Valley and German Aischgrund. ► Representative farm models show that the economic situation of carp farmers is harsh today, in particular for smallholders. ► Fisheries Local Action Groups promote the local economy with the carp as core identity. ► It is discussed what positive impact an increased tourism has towards carp farms.

In a search for alternative, environmentally friendly and effective disinfecting agents, a commercially available protease—Neutrase®—was tested in this work for inactivation of koi herpesvirus (KHV) and of viral haemorrhagic septicaemia virus (VHSV). For comparison, the stability of these viral pathogens in similar configurations at various pH values and concentrations of peracetic acid or quicklime, typically used for disinfection, was tested. Therefore, virus suspensions were incubated with various concentrations of different agents for 24 hr and the titre of the remaining infectious particles was determined by virus titration. Furthermore, the treatment of both viruses, with the agents at concentrations that were previously appointed as effective, was also examined in the presence of solid material (quartz sand). All procedures investigated in this study, including the protease treatment, were able to reduce the titre of KHV and VHSV below the detection limit of the titration. Although further studies are necessary, this is the first report of the application of a protease for the inactivation of the selected fish pathogens, demonstrating the great potential of the latter for disinfection.

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Abstract. The mirror carp (Cyprinus carpio) belongs to the cyprinids, the world's largest and most important fish family in aquaculture. The fat content and the fillet yield are important parameters in the marketing of carp. Although the influence of the environment on the body composition of the carp has been well studied, there is little research in the field of breeding. For this purpose, precise phenotyping is indispensable. Therefore, during this study a total of 33 mirror carps were examined using computed tomography (CT) technology. First, the fish were examined alive. Total body weight and linear measurements such as lengths, height and circumferences were measured, and ultrasound was used to determine the back-fat thickness. The fish were then slaughtered and whole body scans of all fish using CT were made. The carps were filleted and the fillets with skin were chemically analyzed. In order to predict the chemical fillet fat content, thickness measurements and volume calculations of the back fat were carried out using CT. Compared to the CT-based back-fat thickness measurement correlated with the results from the chemical analysis (R2=0.62), the CT-based volume measurement of the back fat leads to a higher coefficient of determination (R2=0.85). Prediction results can still be improved by adding linear measurements. The in vivo ultrasound (US) examination of the back-fat thickness was compared with the CT back-fat thickness results. The measurements of the back-fat thickness took place at similar positions in the fish. Coefficients of determination (R2) of 0.63 to 0.77 were obtained. The back fat in mirror carp proved to be an interesting area for determining the fillet fat content. The evaluation of the fillet yield resulted in a mean value of 42.89 % with a standard deviation of ±2.43. Fillet yield (%) correlated with CT-based fillet thickness measurement resulted in a moderate coefficient of determination (R2 of 0.45). A similar coefficient of determination was achieved with selected linear measurements.

Background: Detection of delayed cerebral ischemia (DCI) in high-grade subarachnoid haemorrhage (SAH) is an unsolved issue. Conventional near-infrared spectroscopy (NIRS) with optodes applied over the skin is controversial because the NIRS signal is contaminated by extracerebral tissue. The objective is to quantify and subtract the contribution from extracerebral tissue from the signal by using measurements in parallel with a NIRS brain tissue probe and conventional NIRS.Methods: In a patient with high-grade SAH, two approaches for NIRS were applied. First, a conventional brain tissue probe for intracranial pressure (ICP) monitoring, supplied by optical fibres, was placed into the brain tissue 2 cm deep from the dura. Second, for conventional NIRS, a plaster-based patch carrying optodes (one emitter, two detectors) was attached to the skin. Central venous injections of 0.3 mg/kg body weight (bw) indocyanine green (ICG) were performed. ICG dye dilution curves obtained with the probe and patch were collected simultaneously and analysed for blood flow values.Results: Twelve measurements in parallel with the probe and patch were performed. Mean cerebral blood flow (CBF) for the probe was higher (24.8 ± 9.1 ml/100 g/min) compared with the values obtained with the patch (for detector 1, extracerebral blood flow [ECBF] mean 5.1 ± 1.8 ml/100 g/min; p = 0.002; for detector 2, 6.6 ± 2.1 ml/100 g/min; p = 0.002).