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Pietsch C.,University of Zürich | Pietsch C.,University of Basel | Katzenback B.A.,University of Alberta | Katzenback B.A.,University of Waterloo | And 6 more authors.
Mycotoxin Research | Year: 2015

The mycotoxin deoxynivalenol (DON) has been shown to regularly occur at relevant concentrations in feed designed for aquaculture use, but little is known about the consequences of its presence on the organisms that consume the DON-contaminated feed. Previous studies indicated a down-regulation of pro-inflammatory responses in carp (Cyprinus carpio L.) after 4 weeks of feeding DON. The present study examined the time course of innate immune responses of carp to orally administered DON. Changes in mRNA levels of immune genes in different organs (head kidney, trunk kidney, spleen, liver, and intestine) were observed indicating immune-modulating properties of DON. The immune-modulatory effects during the acute phase of DON exposure were characterized by the activation of both pro- and anti-inflammatory cytokines and enzymes in carp. The subchronic responses to DON were characterized by activation of arginases culminating in increased arginase activity in head kidney leukocytes after 26 days of DON treatment. These results suggest profound effects of this mycotoxin on fish in aquaculture. © 2015, Society for Mycotoxin Research and Springer-Verlag Berlin Heidelberg.


Pietsch C.,University of Basel | Michel C.,University of Basel | Kersten S.,Friedrich Loeffler Institute FLI | Valenta H.,Friedrich Loeffler Institute FLI | And 4 more authors.
Food and Chemical Toxicology | Year: 2014

Deoxynivalenol (DON) is one of the most important members of Fusarium toxins since it often can be found in relevant concentrations in animal feeds. The effects of this group of toxins on fish are mostly unknown. The present study shows results from a feeding trial with carp (Cyprinus carpio L.) using three different concentrations of DON (352μgkg-1, 619μgkg-1, and 953μgkg-1 final feed, respectively) which are comparable to levels found in commercial fish feeds. Effects on growth and mass of fish were not observed during this 6weeks lasting experiment. Only marginal DON concentrations were found in muscle and plasma samples. Blood parameters were not influenced although smaller erythrocytes occurred in fish treated with 352μgkg-1 DON. Analysis of antioxidative enzymes in erythrocytes showed increased superoxid dismutase and catalase activities in fish fed the low-dose feed. Immunosuppressive effects of DON were confirmed whereby cytotoxic effects on immune cells only partly explained the impairment of innate immune responses. Exact polarization of the immune system into pro-inflammatory or anti-inflammatory responses due to DON exposure should be clarified in further experiments, especially since the current results raise concern about impaired immune function in fish raised in aquaculture. © 2014 Elsevier Ltd.


Adem H.N.,Pilot Pflanzenoltechnologie Magdeburg PPM E. V. | Tressel R.-P.,Pilot Pflanzenoltechnologie Magdeburg PPM E. V. | Pudel F.,Pilot Pflanzenoltechnologie Magdeburg PPM E. V. | Slawski H.,Gesellschaft fur Marine Aquakultur GMA MbH | Schulz C.,Gesellschaft fur Marine Aquakultur GMA MbH
OCL - Oilseeds and fats, crops and lipids | Year: 2014

The main problem of the aquaculture sector is the provision of suitable and sufficient fish feed, because the most important protein source in aquaculture, the fish meal, is a limited resource. Due to their high nutritional value the rapeseed proteins have great potential as an alternative protein source for the fish nutrition. Therefore, the aim of this work is to develop a manufacturing process of high quality rapeseed protein concentrates, which can replace the limited marine resource. For this purpose, small pilot scale processing procedures were performed to produce a rapeseed protein concentrate (RPC). The meal for protein extraction was prepared by gentle meal processing. Rapeseed protein fractions were prepared by an aqueous extraction procedure. The obtained protein solution is further purified and then dried. The investigated rapeseed protein extraction process provides RPC with high nutritional value and low levels of antinutritional factors. From the nutritional point of view the produced RPC can be compared with the fishmeal. Its amino acid profile reflects the amino acid demands of fish. The obtained RPC was utilized for experimental setups of fish meal replacement in diets for rainbow trout, turbot, common carp and wels catfish. Experimental results from the conducted feeding trials demonstrate an enormous potential of RPC as protein source in aquafeeds. The highest fishmeal replacement level (up to 100%) was observed in the feeding trials with rainbow trout. Therefore, especially in the nutrition of rainbow trout, RPC was identified as an excellent fishmeal alternative. © 2014 H.N. Adem et al., published by EDP Sciences.


Rossner Y.,Gesellschaft fur Marine Aquakultur GMA mbH | Rossner Y.,University of Kiel | Krost P.,Coastal Research and Management CRM | Schulz C.,Gesellschaft fur Marine Aquakultur GMA mbH | Schulz C.,University of Kiel
Journal of Applied Phycology | Year: 2014

Extractive seaweed aquaculture is gaining attention in the western Baltic Sea and in particular the co-cultivation with other species for bioremediation or nutrient delivery. However, there are still limitations to viable seaweed production yields in a brackish habitat with a short production period for Saccharina latissima. This investigation presents the specific growth-enhancing effect of Mytilus edulis on the seaweed early nursery stages during the hatchery and during the grow out period at sea in a Baltic fjord. Gametogenesis and juvenile sporophyte development were evaluated with and without blue mussels during 9 weeks of seaweed hatchery. The presence of mussels resulted in a significantly higher abundance of large multicellular sporophytes. After the hatchery period, seedling lines were transferred into the field and installed both in the direct vicinity of and 25 m away from mussel culture ropes. The previously observed supporting effect of mussel co-culture on seaweed development during the hatchery period was still visible after 6 months at sea. Sporophytes were larger, had a higher biomass and had higher carbon content if previously combined with mussels in the hatchery. This investigation suggests that the co-cultivation of seaweed and mussels during seaweed hatchery can increase seaweed crop yields in the following grow out period at sea, with the possibility of being certified organic. © 2014 Springer Science+Business Media Dordrecht.


Samuel-Fitwi B.,Gesellschaft fur Marine Aquakultur GMA mbH | Samuel-Fitwi B.,University of Kiel | Nagel F.,Gesellschaft fur Marine Aquakultur GMA mbH | Meyer S.,Gesellschaft fur Marine Aquakultur GMA mbH | And 4 more authors.
Aquacultural Engineering | Year: 2013

The production of rainbow trout (Oncorhynchus mykiss Walbaum 1792) is practiced in different production systems including extensive system (ES), intensive system (IS) and recirculating aquaculture systems (RAS). These production systems are different in their quantitative requirements of resource utilization and subsequent output and emissions that impact the environment. In this paper, consequential life cycle assessment (LCA) is used to analyze the environmental impact of rainbow trout production using these production systems in an attempt to determine the relative performances and identify options for future improvements. The life cycle impact assessment (LCIA) indicate that impact from four impact categories chosen, RAS showed the largest impact in global warming (GWP), acidification (AP) and land competition (LC), while its impact on eutrophication (EP) and water-use was the lowest relative to ES and IS. This signified that while RAS has the capability to reduce impacts in the EP category by avoiding water emissions, the increased use of energy for water filtration and reuse increases impact through global emissions. However, sensitivity analysis revealed that RAS has the potential to reduce the overall impact when using a marginal energy source based on wind power as compared to ES and IS. In conclusion, impacts which are specific to aquaculture need to be considered in LCA to draw comprehensive analysis of the impacts. In addition, identification of the underlying problems of the different impacts is important in finding solution leading to sustainability of aquaculture. © 2012 Elsevier B.V.


Samuel-Fitwi B.,University of Kiel | Wuertz S.,University of Kiel | Schroeder J.P.,Gesellschaft fur Marine Aquakultur GMA MbH | Schulz C.,University of Kiel
Journal of Cleaner Production | Year: 2012

Aquaculture production has doubled every decade for the past fifty years, representing the fastest growing food sector. This increase reflects the expansion of production areas, increased know-how in husbandry and advances in production technologies, but most importantly it entails increased use of production-inputs that lead to exploitation of natural resources and hence raising concern on environmental distress. In addition, it suggests a similar range of production-outputs apart from the actual target products that are hardly quantified but often are recognized for causing impacts on the environment as well as potential risks for human health. Although several quantitative multi-impact assessment tools have been explored to evaluate environmental impacts of industrial activities, applications in aquaculture have only recently been carried out. However, impact assessment tools applied so far do not reflect the full range of aquaculture activities, and hence incorporate limitations that impair their use in aquaculture environmental assessment. Therefore, the development of tailored environmental assessment tool incorporating impacts distinctive to aquaculture is necessary. By reviewing recent methodologies used in aquaculture, their limitations are identified and future research needs are highlighted. Although large strides have been made in reaching standardized methods for environmental assessment tools such as life cycle assessment (LCA), their use in policy formulation and decision making requires relentless effort to develop the tools using fundamental problems known to aquaculture. As a prerequisite, the most significant impacts of aquaculture are identified but need to be characterized and integrated in aquacultural assessment tool. Furthermore, social aspects of sustainability should be considered; and linkage of operational efficiency with environmental performance can support in optimizing the allocation of resources while minimizing impacts. © 2012 Elsevier Ltd. All rights reserved.

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