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Introduction: The variety of seafood on the European market has considerably increased in recent years. This study presents data to the main nutritional values and the sensory properties of two exotic fish species, mahi-mahi (Coryphaena hippurus) and emperor sea bream (Lethrinus spp.), sold on retail market in Germany. Information on the quality of frozen and glazed fillets is still missing, but is important to characterize these products. This also includes details on the substances added to increase the water-binding ability. Aims: The paper aims to assess the quality of exotic fish fillets sold on the German market, through the evaluation of physical and chemical parameters, microbiological quality and sensory attributes. Materials and methods: 10 samples of each fish species were analysed after homogenisation to determine the following parameters: pH-value (with a pH meter); water (gravimetrically); ash (in a muffle furnace at 550 °C); salt (NaCl; by auto-titration); fat (by a modified Smedes method); protein (with a LECO TruSpecN based on the principles of the Dumas combustion method); total phosphorus content (photometrically); total volatile basic nitrogen (TVB-N, using the EU reference method); total viable bacteria count (TVC) and specific fish spoiling bacteria (SSO) (by decimal dilutions method). The sensory assessments were done with cooked and fried fillets by a panel consisting of 6 specialists, using a descriptive method. Results: Lipid, ash and salt contents of mahi-mahi were comparable to the emperor sea bream values. Due to low lipid content, both species can be classified as lean species. The protein amount of emperor sea bream was significantly higher compared to mahi-mahi and many other common fish species. In mahi-mahi samples, slightly higher values of total phosphates content were found. The pH values of emperor sea bream were in a normal range for fresh fish, whereas in mahi-mahi significantly higher values were determined which was not correlated with quality deteriorations. TVB-N values in all investigated samples were low and indicate a sufficient fish freshness of the used raw material. The TVC of different mahi-mahi and emperor sea bream fillets indicated a good to sufficient microbiological status. Conclusion: Pleasant sensory properties, low microbiological charge and low fat contents of emperor sea bream and mahi-mahi lead to the conclusion that these exotic fish products are a valuable enrichment of fish products on the market.

A collaborative study for quantification of Anisakis larvae in spiked farmed salmon fillets was conducted by 12 laboratories in 2012, using a modified Codex method (CODEX STAN 244). N = 6 samples with a different number of Anisakis larvae including two blind duplicates were analyzed by participants. All laboratories applied the same modified digestion method with stirring speed of 500–600 rpm, using a triangular stirring bar and a maximum digestion temperature of 35 °C in order to reduce fragmentation of larvae. All participants found correctly no larvae in the control samples while the mean recovery rate of all spiked larvae was 86.6 %. The among-laboratory reproducibility was 16.5 %. Differences were noticed in the interpretation of Anisakis fragments, which occurred as a result of prolonged frozen storage of the samples.

Summary Proximate composition, fatty acid profile, other nutritional values and spoilage indicators were examined in the muscle meat of five species: barramundi (Lates calcarifer) from various origins, tilapia (Oreochromis spp.) of different qualities, cobia (Rachycentron canadum) and leather jacket (Aluterus monoceros) from the Pacific Ocean and Patagonian grenadier (Macruronus magellanicus) from South America. Lowest lipid contents (0.4% and 0.8%) were found in leather jacket and cobia. Leather jacket fillets had lowest protein (16.2%) and highest sodium chloride content (4.9%). Concentrations of ∑EPA + DHA were 0.1 g 100 g−1 for tilapia and leather jacket, 0.2 g 100 g−1 for barramundi and cobia and 0.7 g 100 g−1 for Patagonian grenadier. Barramundi and tilapia were characterised by high taurine content (215 and 276 mg 100 g−1 ww.), and cobia had only low levels (41 mg 100 g−1 ww.). Iodine contents were low and selenium levels varied between 303 and 570 μg kg−1 ww. No sign of spoilage was detected.

Previous studies have shown that Grey gurnard from the North Sea is comparatively heavily infected with the larvae of the parasitic and potentially consumer hazardous nematode Anisakis simplex (s.l.). Especially the high abundance of Anisakis larvae in the fish flesh is of concern regarding the possible intensified utilisation of Grey Gurnard as a food resource. To gain better knowledge of the nematode burden with emphasis on abundance and distribution in the fish flesh, various Grey gurnards from 6 localities across the North Sea, each representing either western, northern or eastern fishing grounds, were examined for anisakid nematodes during summer of 2010 and 2012. The overall prevalence of A. simplex (s.l.) larvae in the gurnards from all localities (n = 188) was nearly total, i.e. only a single fish from the northernmost locality (Viking Bank) was apparently not infected. GLM-analyses revealed that catching locality had by far the strongest effect on larval infection probability, both in total (flesh + viscera) and in the fish flesh, while body size (weight) was a weak but still significant predictor of overall A. simplex (s.l.) abundance, but not in the flesh. Thus, the overall larval abundance in the gurnards from the two western localities off the east-coast of British mainland was significantly higher compared to the other catching localities. In the former localities, the overall mean abundance of A. simplex (s.l.) larvae was 35.0 ± 23.9 and 92.2 ± 87.4, and ranged from 14 to 114 and 9 to 397, respectively. It was further shown that 93.8% of the larvae infecting the fish flesh were situated in the belly flaps, i.e. the ventral portion of each flesh side or fillet, independent of catching locality and fish size. However, trimming of the fillets by removing the belly flaps may reduce the abundance in the fillets to, on an average, 0.3 larvae.

This study discusses the various factors which influence the intake of dioxins and dioxin-like PCBs (dl-PCBs) via fish consumption to support the requirements for additional information for an adequate estimation of consumer’s exposure. Growing consumer preferences towards lean and aquaculture species have to be considered in future. The varying dioxin and dl-PCB levels of herring in relation to the geographical origin and the fishing season and their consequences for the estimation of the exposition are discussed. The levels in herring from different fishing grounds can vary by a factor of 8 between 0.43 and 3.04 ng WHO–PCDD/F–PCB–TEQ2005/kg wet weight. Increasing lipid content of the muscle meat during the feeding cycle of herring and mackerel leads to a “dilution effect” of contaminants based on lipid weight. Changes in the composition of feed for carnivorous species reduced the dioxin levels in farmed salmon and trout considerably between 1997 and 2004. Hence only recently taken data collections should be used for exposure estimation. Furthermore processing and household preparation can change the contaminant levels and should be taken into account.

Summary Proximate composition, fatty acids profiles and other nutritional values were evaluated for fillets of Limanda aspera (yellowfin sole), Lepidopsetta bilineata (southern rock sole) and Lepidopsetta polyxystra (northern rock sole) and compared to North Sea plaice (Pleuronectes platessa). Additional information is given on the composition of fillets from arrowtooth flounder (Atheresthes stomias). Plaice (0.8% lipid) and Alaska soles (1.0–1.2% lipid) can be classified as lean species, resulting in low 0.3–0.5 g ∑EPA+DHA/100 g muscle, although the fatty acid profiles of the extracted lipids were characterised by high amount of n-3 fatty acids (33.2–47.3%). Arrowtooth flounder belong to the medium-fat species (4.3%). Taurine was the most prevalent free amino acid; mean values ranging between 221 mg100 g−1 and 247 mg100 g−1 wet weight. The selenium content varied between 130 and 310 μg kg−1 ww. Sensory attributes of Southern and Northern rock sole were comparable to plaice.

Evolution or revolution? Medical imaging is in a transition from a qualitative to a fully digital, quantitative discipline with fast growing numbers of images and increasing need for multimodal, multidisciplinary assessment. Computer assistance is a key ingredient to efficiency, safety, and quality of care in this domain. With the availability of prior scans in digital format, and with the diversification of the clinical application domains, both data complexity and requests for specialized and integrated tools are rapidly increasing. We will compare radiological imaging with the situation we currently face in digital pathology and discuss major implications and challenges for the future development of computer assisted medical imaging as key technology for modern healthcare. We cover both methodological research and clinical adaptation, ranging from modular and prototypical software integration to prospective clinical evaluation and medical device product integration. For any clinical use of new solutions, quality assurance is performed according to the guidelines defined by the FDA and other regulatory bodies, which represents a particular challenge for novel data driven and self-learning software systems. In addition, decentralized infrastructures including cloud computing will support efficient collaborative research. Medical image computing, quantitative analysis, auto- mated detection of clinically relevant findings, and computerized classification of disease patterns is expected to have major impact on solutions and workflows used in future clinical routine and in large clinical trials. For digital pathology, the automated and robust combination of information across multiple slides will be a key success factor. A major challenge rests on the barriers and costs of validation of a variety of new solutions and their integration into the routine clinical workflow., Diagnostic Pathology, Vol 1 No 8 (2016): 13. European Congress on Digital Pathology

The use of parasites as biological tags for discrimination of fish stocks has become a commonly used approach in fisheries management. Metazoan parasite community analysis and anisakid nematode population genetics based on a mitochondrial cytochrome marker were applied in order to assess the usefulness of the two parasitological methods for stock discrimination of beaked redfish Sebastes mentella of three fishing grounds in the North East Atlantic. Multivariate, model-based approaches demonstrated that the metazoan parasite fauna of beaked redfish from East Greenland differed from Tampen, northern North Sea, and Bear Island, Barents Sea. A joint model (latent variable model) was used to estimate the effects of covariates on parasite species and identified four parasite species as main source of differences among fishing grounds; namely Chondracanthus nodosus, Anisakis simplex s.s., Hysterothylacium aduncum, and Bothriocephalus scorpii. Due to its high abundance and differences between fishing grounds, Anisakis simplex s.s. was considered as a major biological tag for host stock differentiation. Whilst the sole examination of Anisakis simplex s.s. on a population genetic level is only of limited use, anisakid nematodes (in particular, A. simplex s.s.) can serve as biological tags on a parasite community level. This study confirmed the use of multivariate analyses as a tool to evaluate parasite infra-communities and to identify parasite species that might serve as biological tags. The present study suggests that S. mentella in the northern North Sea and Barents Sea is not sub-structured.

Lipid determination by the Smedes method was tested in an interlaboratory trial performed by nine laboratories from seven countries belonging to the West European Fish Technologists Association Analytical Methods Working Group. Five samples of fish and fishery products with different lipid contents, including two blind duplicates, were distributed among the participants. All laboratories applied a slightly modified Smedes method, which included extraction of lipids by cyclohexane and isopropanol, transfer of lipids to the cyclohexane phase by addition of water, phase separation by centrifugation, and gravimetric lipid determination. The results indicate that the RSD for reproducibility (RSDR) was between 4.11 and 6.31% for samples with moderate (7%) and high (14%) lipid content, depending on the sample. Larger SDs among the laboratories were obtained for a cod sample with low lipid content of 0.5%. The method is judged to be suitable as a routine method for lipid determination in fish and fishery products.

140 Milcherzeugnisse aus verschiedenen Regionen Deutschlands wurden 2006 auf Dioxine, dioxinahnliche PCB und nicht dioxinahnliche PCB untersucht. Insgesamt wurden 66 Kase-, 23 Butter- und 51 Quark- bzw. Joghurterzeugnisse analysiert. Die Probenahme erfolgte in Supermarkten und Einzelhandelsgeschaften auf der Basis der Produktionsmengen in den einzelnen Bundeslandern der Bundesrepublik Deutschland. Die Dioxinkonzentrationen und die Summe der WHO-TEQ blieben weit unter den EU-Grenzwerten von 3 pg WHO-PCDD/F-TEQ/g Fett und 6 pg WHO-PCDD/F-PCB-TEQ/g Fett. Die Dioxingehalte lagen bei niedrigen 0,07–0,53 pg WHO-PCDD/F-TEQ/g Fett mit einem arithmetischen Mittelwert von 0,19 pg WHO-PCDD/F-TEQ/kg Fett. Die WHO-PCDD/F-PCB-TEQ Gehalte lagen zwischen 0,21 und 2,1 pg WHO-TEQ/g Fett, mit einem mittleren Gehalt von 0,76 pg WHO-TEQ/g Fett. Regionale Abhangigkeiten und Unterschiede zwischen den einzelnen Produktgruppen konnten nicht festgestellt werden. Langjahrige Messungen der Dioxingehalte in Butter und Kase aus Schleswig-Holstein zeigen uber den Zeitraum von 13 Jahren eine deutliche Abnahme der Gehalte von 0,43 auf 0,19 pg WHO-PCDD/F-TEQ/g Fett.

Grey gurnard ( Eutrigla gurnardus L.) is an abundant and widely distributed demersal fish in the North Sea. It is currently considered a sustainable stock, thus permitting future increased utilisation as a food resource. In order to address both consumer safety and aesthetical product quality, the occurrence and distribution of anisakid nematode larvae in Grey gurnard from two localities in the North Sea were investigated. Two anisakid species were recorded, i.e. Hysterothylacium aduncum in the viscera, and Anisakis simplex in both the viscera and flesh of the fish. Virtually all gurnards were infected with nematode larvae. However, H. aduncum was significantly less abundant than A. simplex in the fish from both localities. Only for the gurnards from the northernmost sampling locality there was a significantly positive correlation between host body weight and total A. simplex abundance. No such correlation was found for H. aduncum in either locality. Separate analyses of the Anisakis infection data in gurnards of marketable size (≥250 g) and pooled for both localities, revealed 83% prevalence of A. simplex larvae in the fish flesh, ranging 1–16 in intensity. The relative larval distribution between the viscera and flesh was 89 and 11%, respectively. Moreover, a significantly positive correlation was found between A. simplex occurring in the viscera and the flesh of this particular host size group, i.e. the number of larvae in the flesh appeared to increase with increasing infection level in the viscera. In general, Grey gurnard from the North Sea can be considered as heavily infected with nematode larvae. Especially the comparatively high abundance of A. simplex larvae in the flesh is of concern regarding the possible intensified utilization of Grey gurnard as a food resource.

The study of the beryciform Anoplogaster cornuta from the Irminger Sea (north Atlantic) revealed the presence of the anisakid nematode Anisakis paggiae inside the body cavity, representing a new host and locality record. This deep-sea fish was infected with Anisakis larvae at a prevalence of 57.1% and a mean intensity of 2.2, with no correlation between the fish standard length and the number of accumulated A. paggiae. Kogiid whales (Kogia breviceps, K. sima), the typical final hosts of this parasitic nematode, have not yet been recorded so far in the north. Because A. cornuta does not migrate outside the Irminger Sea, and by using the parasite as an indicator for the presence of the final hosts, A. paggiae must have been introduced through migratory kogiid final hosts. This would extend their range of distribution into the Irminger Sea. The depth range of the meso- and bathypelagic A. cornuta and the frequent occurrence of Anisakis inside this deep-sea fish demonstrate an oceanic deep-water life cycle for A. paggiae in the north Atlantic.

Up to now the visual inspection of mobility of isolated anisakid larvae serves as a measure of viability and possible risk of infection. This paper presents a new method to rule out unreliability – caused by the temporary immobility of the larvae and by the human uncertainty factor of visual observation. By means of a Near infrared (NIR) imaging method, elastic curvature energies and geometric shape parameters were determined from contours, and used as a measure of viability. It was based on the modelling of larvae as a cylindrical membrane system. The interaction between curvatures, contraction of the longitudinal muscles, and inner pressure enabled the derivation of viability from stationary form data. From series of spectrally signed images within a narrow wavelength range, curvature data of the larvae were determined. Possible mobility of larvae was taken into account in statistical error variables. Experiments on individual living larvae, long-term observations of Anisakis larvae, and comparative studies of the staining method and the VTD measurements of larvae from the tissue of products confirmed the effectiveness of this method. The VTD differentiated clearly between live and dead nematode larvae isolated from marinated, deep-frozen and salted products. The VTD has been proven as excellent method to detect living anisakid nematode larvae in fishery products and is seen as useful tool for fish processing industry and control authorities.

A range of conventionally and organically farmed Pangasius or sutchi catfish fillets available on the German market were analysed to compare both composition and quality. Differentiation of Pangasius hypophthalmus from Pangasius bocourti was achieved by RFLP-SSCP analysis. The protein content of conventionally farmed fillets ranged between 13.3 and 15.7%, whereas organically produced fillets had significantly higher protein contents of between 17.0 and 17.4%. No difference in the fat content between farming methods was observed, which varied between 1.4 and 3.2%. Polyunsaturated fatty acids represented about 24% of the total fatty acids with a high level of linoleic acid. The comparison of the proximate composition indicated that water was added to most of the conventionally farmed products, in different amounts, as well as water-binding capacity enhancing additives. Differential scanning calorimetry was used to demonstrate the presence of polyphosphate on muscle proteins. Differences in texture, water-binding capacity and colour are discussed.

The contaminant levels of dioxins, dioxin-like PCBs and non dioxin-like PCBs were determined in pooled samples of cod liver and corresponding cod muscle from different fishing grounds of the North- and Baltic Sea and from East Greenland. The dependence of the contaminant concentrations was studied on cod of three different sizes caught at the same fishing ground. Samples were taken during different research trips at 11 fishing grounds of the Baltic Sea, and 3 fishing grounds of the North Sea and of East Greenland in 2006 and 2007, respectively. Cod liver from the Baltic- and the North Sea were highly contaminated. Mean concentrations were 93 and 83 ng WHO-TEQ/kg wet weight (w.w.), respectively. Cod livers from East Greenland had only low contaminant levels of 3.4 ng WHO-TEQ/kg w.w. Highest concentrations were found in livers from the Bay of Kiel. Within the same fishing area the concentrations increased with the size of the cod. The WHO-TEQ amounts of the cod fillets were below 1 ng WHO-TEQ/kg w.w. and thus within the commonly observed low range for lean fish.

Concentrations of polychlorinated dibenzodioxins, dibenzofurans and dioxin-like PCBs in the edible part of fish and in fishery products were studied to gain an overview on actual contaminant levels on the German market.

The survival of Anisakis sp. larvae in herring fillets marinated in brines with different concentrations of salt (NaCI) and acetic acid was examined. Traditional German and Danish procedures for marinating herring fillets require a storage time of at least 5 and 6 weeks, respectively, for all larvae to be killed. Other concentrations of salt and acetic acid were also studied. A reduction of the salt content in the water phase of the fish tissue from 9% (w/w) to 4.3% (w/w), while keeping the concentration of acetic acid constant at 2.6%, increased the survival time of the nematodes from at least 35 days to more than 119 days. Increases in the acetic acid concentration or the addition of potassium sorbate had little or no effect on the viability of the larvae.

Fish among meat and dairy products mainly contribute to the human exposition with dioxins and dioxin-like PCBs. Contaminant levels of fish are mainly determined in the edible part of the raw material. In Germany fish are not consumed raw but industrially processed to manifold products and cooked, fried or deep-fried in household. To study the influence of processing on the contaminant levels, changes of dioxins and partly of dioxin-like PCBs were followed during canning of herring fillets, hot smoking of mackerel fillets and Greenland halibut cutlets and during sugar salting of beheaded whole herring. The hot smoking process and sugar salting of herring led to an increase of the dioxin content in the edible part of the final product. The increase was related to the loss of water during processing whereas the fat and thus the lipophilic dioxins remained in the muscle meat. For sugar salting also changes of dioxin-like PCB levels were followed and the same effect was observed. Otherwise the production of canned herring fillets in tomato sauce led to a “dilution” of the dioxin content due to the addition of the sauce.

Comparative ice storage experiments were performed to study the influence of early gutting on the shelf life of gutted and ungutted saithe, plaice and haddock. The investigation included the rating of the external quality attributes according to the EU-quality grading scheme, the sensory assessment of cooked fillets, the chemical analysis of changes in the contents of the total volatile bases (TVB), trimethylamine (TMA) and dimethylamine (DMA), of total viable counts (TVC) and the number of specific spoilage bacteria (SSO) Shewanella putrefaciens on skin and tissue samples.

eingereicht von: Horst Pichler Mit deutscher Zusammenfassung Universität Linz, Univ., Diplomarbeit, 2015

Tilletia caries is a fungus that mainly infects wheat, causing the disease bunt. Wheat bunt had been one of the most dangerous plant diseases before seed dressing was a common practice. However, it is still of importance in organic farming, since seed dressing is not permitted. Trimethylamine (TMA) is a metabolic product of T. caries known to cause a fishy odour of highly contaminated wheat. Therefore, contamination of feed is supposed to decrease feed intake. However, systematic studies on the effect of practically relevant proportions of bunt-infected wheat on performance and health of pigs are not available. Therefore, the aim of the present study was to investigate the effects of increasing proportions of bunt-infected wheat (0%, 10%, 20% and 30% of the diet) corresponding to a total spore content of 0%, 0.2%, 0.4% and 0.6% on the performance and health of piglets during a 5-week experiment starting after weaning. TMA was not detectable in the contaminated wheat and the feed intake of piglets remained unaffected. However, live weight gain decreased linearly and feed-to-gain ratio significantly increased as the proportion of contaminated wheat increased. Haematological and serum clinical-chemical characteristics as well as the viability of peripheral blood mononuclear cells were not influenced by dietary treatments. Based on the limited data of the present experiment it might be concluded from the adverse effects of bunt-infected wheat in piglet diets on the feed-to-gain ratio that a spore content of 0.2% of the complete diet should not be exceeded.

The distribution of Anisakis larvae in fresh caught hake was studied, and the influence of three infection levels of the viscera (low, medium, high) on quality changes of deep frozen muscle was followed over 220 days. Differences in quality were attributed more to the size of the individuals than to the infection degree of the three groups. The removal of belly flaps diminished the risk of consumers infection and sensitization as prevalence and intensity was reduced to 75.6 and 5.9%, respectively. Allergens were detected after 220 days frozen storage, which represents a risk for consumers already allergic to Anisakis., This work was partly financed by the Spanish projects AGL2005-05699-C02-01/02 and AGL2009-12485-C03-01/03

Three toxaphene indicator compounds were determined in fish oil and fish meal of different origin and raw material as well as in feed containing fish oil and fish meal. Fish oil and fish meal from South America contained no or only traces of the indicator congeners. The sum of the three compounds varied in fish oils from Europe between 13 micrograms/kg fat (sand eel oil) and 206 micrograms/kg fat (cod oil). Varying concentrations were also determined in European fish meal and in feed. Toxaphene indicator compounds were as well detected in trout and salmon fed with toxaphene residues containing feed. Results indicate that feed can contribute to toxaphene contamination of farmed salmon from Europe.

Cis-, trans-, oxychlordane and trans-nonachlor were determined in the edible part of more than 140 fish samples of 15 different species and in fish meal, -oil and fish feed. The investigated fish included most of the important fish species consumed in Germany. Highest concentrations were found in muscle of marine fish with high or moderate fat content, but also in eel and farmed salmon. Marine fish with low fat content contained only traces of chlordane in the muscle tissue. A relationship between fishing ground and levels of chlordane could not be established. Contamination level of herring was related to the age (length) of the fish. Data are also given for contamination levels of fish meal, -oil and -feed.

Three toxaphene indicator compounds were determined in more than 100 samples of fish. The investigated fish included nearly all important fish species consumed in Germany. Highest residue concentrations were found in marine fish with high or moderate fat content, e.g. halibut, herring, redfish and mackerel. In fresh water species and marine fish with low fat content less contamination was found. A significant relationship between the fishing ground and the toxaphene residue could not established. Contamination levels of most species were related to the age (length) of the fish. The daily intake of total toxaphene in Germany was estimated at 2.8–5.6 ng/kg body weight.

European smelt Osmerus eperlanus (n = 501) from the German Wadden Sea (North Sea) near the city of Cuxhaven were examined for their infestation with parasitic anisakid nema- todes, especially with sealworms of the genus Pseudoterranova. The distribution of third-stage lar- vae (L3) in the musculature and viscera of the fish was analyzed. In total, we isolated 543 L3 from the hosts' body cavity and musculature. A subsample of 105 larvae were identified as the (sibling) species P. decipiens s.s. using direct sequencing of the highly variable ribosomal ITS1-5.8S-ITS2 genetic marker. The mean abundance was 1.1, the mean intensity was 2.3 P. decipiens s.s. and the prevalence was 47.3%. Total length and total weight, but not Fulton's condition factor (K), were significantly different in infected compared to uninfected smelt. No correlation was found between the total length of infected fish and the intensity of anisakid nematodes. The vast major- ity of P. decipiens s.s. was found in the musculature of the smelt. More than half (55.7%) of all nematodes were located in the 3 parts of the epaxial musculature, whereas 18.4 and 26.0% were found in the hypaxial musculature and the compartments of the tail muscles, respectively.

The prevalence, mean intensity and distribution of Anisakis nematode third-stage larvae (L3) in the muscle and viscera of wild-caught chum salmon Oncorhynchus keta, pink salmon O. gorbuscha and sockeye salmon O. nerka were compared immediately after catch. Salmon were collected during the fishing season in July 2007 in Bristol Bay and Prince William Sound close to Cordova, Alaska (USA). All fish were infected, and more than 90% of the nematode larvae were found in the edible muscle meat. The isolated anisakid L3 were genetically identified as A. simplex (s.s.). The distribution of nematodes in the muscle meat of fresh-caught salmon was examined in 49 O. keta, 50 O. nerka and 12 O. gorbuscha from Cordova. Most of the larvae were detected in the muscle parts around the body cavity, but nematodes were also found in the tail meat and epaxial muscle (loins). The mean intensity of Anisakis larvae in the edible part was 21 individuals for O. gorbuscha, 62 individuals for O. keta and 63 individuals for O. nerka. No difference in the intensity of Anisakis larvae in the hypaxial muscle was found between fresh-caught and immediately gutted salmon and individuals stored ungutted for 24 h either on ice or in refrigerated sea water.

Fifty-four eel samples from 11 different countries were analysed by capillary gas chromatography for levels of the pesticides aldrin, endrin, hexachlorobenzene, alpha- and beta-BHC, lindane, heptachlor, octachlorostyrene, pp'-DDT, pp'-DDD, pp'-DDE, and for the levels of the PCB congeners 28, 52, 101, 138, 153, and 180. Wild eels, especially from the Baltic Sea area, had elevated contents compared to farmed eels. The mean contamination level reached only 1-5% of the allowable values given by German directives and never exceeded the official limits.

The behavior of larvae of Anisakis sp. in North Sea herring (Clupea harengus) after capture was examined by a sensitive quantitative method (digestion). In one winter and one summer experiment, the mean numbers of worms in freshly caught herring were 0.06 and 0.09 (in double fillets), 0.19 and 0.24 (in double belly flaps), and 10.4 and 7.8 larvae (in viscera), respectively. In each experiment herrings were stored ungutted for up to 5 1/2 d on ice (0°C), in refrigerated/chilled sea water (-10°C), or in warm sea water (10°C), but no changes in the numbers of Anisakis larvae in the belly flaps and the fillets could be demonstrated. The present results show that Anisakis larvae are present in the flesh of herring already at capture, but no significant postmortem migration into the flesh could be demonstrated during storage. Thus, immediately gutting on board cannot eliminate or even reduce the risk from eating raw or inadequately processed herring.

In this paper, a fast and robust graph-based approach for boundary estimation of fiber bundles derived from Diffusion Tensor Imaging (DTI) is presented. DTI is a non-invasive imaging technique that allows the estimation of the location of white matter tracts based on measurements of water diffusion properties. Depending on DTI data, the fiber bundle boundary can be determined to gain information about eloquent structures, which is of major interest for neurosurgery. DTI in combination with tracking algorithms allows the estimation of position and course of fiber tracts in the human brain. The presented method uses these tracking results as the starting point for a graph-based approach. The overall method starts by computing the fiber bundle centerline between two user-defined regions of interests (ROIs). This centerline determines the planes that are used for creating a directed graph. Then, the mincut of the graph is calculated, creating an optimal boundary of the fiber bundle.

In this study, we researched the presence of anisakids in specimens of Merluccius merluccius caught in the area of Little Sole Bank, in the Northeast Atlantic, and found that 100% of the European hake examined were infected and showed high average values of abundance (976.88) and intensity (976.88). The larvae were identified in morphological terms as morphotype type I and in molecular terms as Anisakis simplex s.s via polymerase chain reaction (PCR) restriction fragment length polymorphism of the rDNA. The genetic variability of the A. simplex s.s population in the North Atlantic is notable, with at least two ribosomal and three mitochondrial haplotypes which are different from the specimen used as control, reflecting the diversity of this species, an aspect which has scarcely been studied to date. The cox-2 gene appears to be an interesting candidate for generating new genetic markers which can be applied to differentiate between A. simplex s.s and Anisakis pegreffii. We detected 11 fixed differences in this gene, and it also offers the advantage of being easily amplified by PCR. The high prevalence of infection by A. simplex s.s and the extremely high average intensity and abundance values can have significant repercussions on public health, especially among populations which regularly eat insufficiently cooked or raw fish and have a certain genetic predisposition; the genetic variability of the parasite could be another factor to take into account.

To study the time trend of PCDD, PCDF and dl-PCB levels in the muscle of herring from the Western Baltic Sea, samples were collected in 2006 at the same fishing locations as in 1999. The results demonstrated no obvious change in contamination levels based on content in fat during the last 7 years. The site-dependent increase in WHO-PCDD/F-PCB-TEQ concentrations already found in 1999 in fishing grounds between the Skagerrak and the east of Bornholm could be confirmed by this study. In addition, an overview is given in this study on the actual WHO-TEQ concentrations in cod, eel, herring, sprat and some salmon landed at various fishing ports along the coast of Mecklenburg-Western Pomerania/Germany. All herring samples were found to be below the maximum levels and the concentrations in cod were below 1 ng WHO-TEQ kg−1 wet weight (ww). The contaminant levels of 28 pooled eel samples varied considerably between 1.35 and 16.75 ng WHO-TEQ kg−1 ww. The results are discussed in relation to the fat content and to the weight of the eels.

This study was carried out in two research centres which are Centre 1 in Germany and Centre 2 in Ireland. In Centre 1, canning experiments were carried out by using blue whiting that had quality which was principal to be used as a raw material for canned products. However the quality was inferior when compared with commercial canned herring product in tomato sauce that is well accepted in German market. Centre 2 involved evaluation of the shelf life and sensory panel of blue whiting fillets. The blue whiting was sourced as block frozen fillets and individually quick frozen (IQF) fillets. They were tempered and evaluated as chilled fillets packed in modified atmosphere (MAP), or in air to assess their potential suitability for sale from chilled retail markets. Outcomes suggests that chilled Blue whiting fillets originating as block frozen or IQF samples have potential for sale in retail packs at 2-4°C, especially when packed in MA and when cooked by pan frying. These have a high quality shelf life of about 5 days at 2-4°C. Frozen breaded blue whiting goujons and nuggets were also well accepted. Further research was undertaken to observe some trace elements and cholesterol content in the muscle of blue whiting.

This thesis brings quantitative methods on complex medical image data closer to clinical routine, and bridges the gap between manual and automated processing. Efficient and effective image segmentation methods are described, and applied to currently insufficiently solved problems that are relevant for medical diagnosis and therapy monitoring. The methods are designed to be suitable for software assistants that meet the requirements imposed by a quantitative analysis in clinical imaging: Applicability regarding the required hardware and acquisition protocols, as well as an effective and intuitive user control, robustness to variations of image quality and also of anatomy and pathology, precision of all derived quantitative measures, sensitivity with respect to relevant changes of the examined structures, and efficiency in order to be applicable to very large data sets on standard hardware. The first part of this thesis describes novel methods that build upon and extend the morphological watershed transform that is known as the key concept for image segmentation in Mathematical Morphology, with applications to brain segmentation in magnetic resonance imaging as well as bone removal in computed tomography and CT angiography. The second part focuses on quantitative image analysis in general, as well as the volumetry of specific neuroanatomical structures in particular. Morphological Volumetry is proposed as a framework for the reliable volumetric quantification of complex three-dimensional structures found in tomographic medical images, combining the extended watershed transform and automated histogram analysis. In cooperation with clinical and industrial partners, the proposed methods were successfully evaluated on a great variety of patient and volunteer images, as well as on software phantoms. The methods have shown potential to improve medical diagnosis and quantitative therapy monitoring and to enhance objectivity in medical image analysis in various instances.

In 1995-1998 the contents of polychlorinated dibenzodioxins and dibenzofurans of 184 pooled fish samples were analysed. Sampling focused on fish and fishery products with a market share of more than 1% and covered all fishing grounds important for the supply of the German market. Investigation included 15 different fish species, shrimp, mussel and squid samples and various fishery products, typically on the German market. Generally lean fish species like cod, saithe or Alaska pollock were less contaminated on fresh weight basis than fat fish species like herring, Greenland halibut and sardine. In herring the dioxin content is related to the fishing ground. Low concentrations were found in North Sea herring, high concentrations measured in samples from the Baltic Sea. Dioxin contents in fishery products did not differ significantly from the raw fish samples. Results allow an estimation of the daily intake of dioxins and furans via fish consumption in Germany. Based on a daily fish consumption of 20 g the average intake of dioxins via fish is 6.2 pg WHO-PCDD/F-TEQs per person and day.

The FAO/WHO Codex Alimentarius Commission has laid down a Codex standard for salted and dried salted fish which requires an official determination method of the salt content. A draft of an analytical method has been elaborated by a Codex working group and the WEFTA working group on analytical methods and was asked to validate this method. Seventeen laboratories out of 10 countries participated in a WEFFA collaborative trial on salt determination in fish and fishery products. Four samples containing different salt contents were distributed, including two spiked samples and two typical commercial products. All laboratories applied a common method involving the precipitation of fish proteins by Carrez I and II followed by titrimetric determination of the salt content according to Mohr. They also carried out salt determination by their own >home> methods. The following results were obtained: The recovery rate of the common method was nearly quantitative and the relative standard deviation for reproducibility was between 1.96 and 2.64%, depending on the sample. Larger variations were obtained between different laboratories when applying their home methods. In one sample a significant difference of the measured salt content was found between the average results of the common and the home methods. Application of ashing of the sample before salt determination always yielded in lower salt contents compared to other determination procedures. The common method is judged to be suitable as a standard method for salt determination in fish and fishery products.

The levels of 13 polycyclic aromatic hydrocarbons (PAH) were determined by an HPLC method with fluorescence and UV detection and by a GC/MS technique in smoked fishery products from modern smoking kilns with external smoke generation and from traditional smoking kilns. The average benzo(a)pyrene (BaP) concentration of all 35 samples from commercial smoking kilns with external smoke generation was 0.1 microgram/kg (wet weight) and the sum of the carcinogenic compounds determined in the study, i.e. benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene and indeno(1,2,3-c,d)pyrene did not exceed 4.5 micrograms/kg (wet weight). The BaP levels of the 27 smoked fish samples from traditional kilns ranged from 0.2 microgram/kg to 4.1 micrograms/kg, with a mean value of 1.2 micrograms BaP/kg. The average concentration of the sum of the carcinogenic compounds was 9.0 micrograms/kg. Large variations were found in the content of the non-carcinogenic PAHs phenanthrene, anthracene, fluoranthene and pyrene in all samples from both types of smoking kilns.