Search

Abstract: High dietary content of vegetable oil (VO) has been associated with increased intestinal lipid accumulations in fish. The extent of this in aquacultured Atlantic salmon (Salmo salar L.) and its health effects are not certain. Samples were therefore collected from two separate feeding trials to investigate the effect of high dietary VO on intestinal lipid accumulations in Atlantic salmon. In the first trial, the fish were fed diets high in plant protein and with fish oil or ~80% of the fish oil replaced with either olive oil, rapeseed oil or soybean oil in a land‐based experimental set‐up. The second trial was performed in sea cages under commercial production conditions, and the fish were fed two dietary concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (9.7% or 5.5% EPA + DHA of total fatty acids). Neither dietary VO nor variations in EPA and DHA led to any significant effects on intestinal health or lipid accumulations. There were, however, indications of a delayed lipid transport in the rapeseed oil‐fed fish of the first trial, possibly caused by high dietary ≥18‐carbon fatty acids and low dietary 16:0 fatty acid and cholesterol. [ABSTRACT FROM AUTHOR]

This work studies final nutritional status and transcriptional responses of rainbow trout (Oncorhynchus mykiss Walbaum 1792) (28 g) after a 10 week feeding experiment designed to elucidate the effect of adding a vitamin and mineral premix on growth, health, and nutritional endpoints. Juvenile fish were fed a either a diet supplemented with a vitamin and mineral premix (Diet S) or the same diet without premix supplementation (Diet U). The analyzed micronutrient composition of diets differed accordingly. Pooled livers from 15 fish from each dietary group were used to create suppression subtractive hybridization (SSH) cDNA libraries that were sequenced with 454 FLX GS Titanium Technology. In total 552 812 reads were sequenced from the two cDNA libraries. Ingenuity pathway analysis (IPA) was then used to characterize the hepatic transcriptome of the two dietary groups of rainbow trout. In the present communication we discuss how selected micronutrients may affect the transcriptome at suboptimal status by directly impacting the cellular metabolism, functions, and structures, and by introducing respective compensatory mechanisms. Processes related to lipid metabolism, peptide hydrolysis, oxygen transportation, and growth development were mostly affected. Considering the transcriptomics data relative to changes in nutritional status from the feeding study and the background phenotypic outcome of growth performance and gill histopathology, the outcome of the transcriptional profiling are suggested to be mainly related to suboptimal pantothenic acid and vitamin C nutrition. [ABSTRACT FROM AUTHOR]

The article presents the author's address on the completion of 10 years of the journal "Aquaculture Nutrition." Over the last decade, the journal has seen a gradual increase in contributions of a high scientific standard. The journal's increasing citation index is just one indicator of the success of the journal as a global supplier of knowledge in this field, vital to the future development of aquaculture. The vision of the present editors is to strengthen the global position of "Aquaculture Nutrition" and to ensure that it is the number one journal within its core area. "Aquaculture Nutrition" is actively working toward online submission.

Abstract: The presence of the organochlorine pesticide endosulfan in the water column confers a significant direct risk to the biota therein, yet relatively little is known regarding the toxic impact of dietborne endosulfan to aquatic organisms. Pre-smolt Atlantic salmon (Salmo salar) were fed at levels of technical endosulfan equal to the European Union regulatory limit (5μgkg−1) and at levels 10 and 100 times greater, for a total of 49 days with haematology (e.g. erythrocyte count, haemoglobin, haematocrit, white blood cell composition), blood biochemistry (e.g. serum aminotransferase, plasma ions) and growth parameters (e.g. condition factor) recorded at days 0, 14, 35, and 49. Toxicological assessment of the individual α and β-isomers that comprise technical endosulfan was also attempted. No mortality was observed in any group during the experiment. In the groups exposed to the control, 5, and 50μgkg−1 technical endosulfan feeds no significant alterations in any measured parameters were determined at any time point. No differences were observed between the technical mixture and the individual α and β-isomer treatment groups. Condition factor was significantly reduced in fish exposed to 500μgkg−1 at day 49, while haematocrit, haemoglobin and mean corpuscular haemoglobin were significantly elevated after 35 days of exposure to the same dietary level, but returned to control levels by day 49. The present study shows that with regards to acute toxicity, Atlantic salmon are able to tolerate dietary technical endosulfan levels up to 500μgkg−1. [Copyright &y& Elsevier]