Co-diversification of an intestinal Mycoplasma and its salmonid host.

Understanding the evolutionary relationships between a host and its intestinal resident bacteria can transform how we understand adaptive phenotypic traits. The interplay between hosts and their resident bacteria inevitably affects the intestinal environment and, thereby, the living conditions of both the host and the microbiota. Thereby this co-existence likely influences the fitness of both bacteria and host.

Assessing Mineral Availability in Fish Feeds using Complementary Methods Demonstrated with the Example of Zinc in Atlantic Salmon.

Assessing the availability of dietary micro-minerals is a major challenge in mineral nutrition of fish species. The present article aims to describe a systematic approach combining different methodologies to assess the availability of zinc (Zn) in Atlantic salmon (Salmo salar). Considering that several Zn chemical species can be present in an Atlantic salmon feed, it was hypothesised that Zn availability is influenced by the Zn chemical species present in the feed.

A transcriptomic analysis of diploid and triploid Atlantic salmon lenses with and without cataracts.

To avoid negative environmental impacts of escapees and potential inter-breeding with wild populations, the Atlantic salmon farming industry has and continues to extensively test triploid fish that are sterile. However, they often show differences in performance, physiology, behavior and morphology compared to diploid fish, with increased prevalence of vertebral deformities and ocular cataracts as two of the most severe disorders. Here, we investigated the mechanisms behind the higher prevalence of cataracts in triploid salmon, by comparing the transcriptional patterns in lenses of diploid and triploid Atlantic salmon, with and without cataracts.

Recommendations for dietary level of micro-minerals and vitamin D to Atlantic salmon () parr and post-smolt when fed low fish meal diets.

Atlantic salmon () feeds have changed drastically in their composition from being predominantly marine-based to plant-based. This has altered the dietary supply and availability of micro-nutrients to Atlantic salmon. The impact of graded inclusion levels of a nutrient package (NP) comprising of 25 different micro-nutrients were studied in Atlantic salmon parr in freshwater (Trial 1) and post-smolts in seawater (Trial 2).

Tracking pollutants in dietary fish oil: From ocean to table.

Dietary fish oil used in aquafeed transfers marine pollutants to farmed fish. However, the entire transfer route of marine pollutants in dietary fish oil from ocean to table fish has not been tracked quantitatively. To track the entire transfer route of marine pollutants from wild fish to farmed fish through dietary fish oil and evaluate the related human health risks, we obtained crude and refined fish oils originating from the same batch of wild ocean anchovy and prepared fish oil-containing purified aquafeeds to feed omnivorous lean Nile tilapia and carnivorous fatty yellow catfish for eight weeks.

Chemical characterization of 21 species of marine macroalgae common in Norwegian waters: benefits of and limitations to their potential use in food and feed.

Background: In the past few years, much effort has been invested into developing a new blue economy based on harvesting, cultivating and processing marine macroalgae in Norway. Macroalgae have high potential for a wide range of applications, e.g.

A comparative study: Difference in omega-6/omega-3 balance and saturated fat in diets for Atlantic salmon (Salmo salar) affect immune-, fat metabolism-, oxidative and apoptotic-gene expression, and eicosanoid secretion in head kidney leukocytes.

The aim of this study was to compare how different dietary vegetable oil n-6/n-3 ratios affect gene responses involved in inflammation, signaling pathways, fatty acid synthesis and oxidation, oxidation and apoptosis as well as eicosanoid production in salmon head kidney tissues and isolated head kidney leukocytes. Salmon smolts (200 g) were fed four different diets where the main lipid components were palm oil (n-6/n-3 ratio = 0.7), rapeseed oil (n-6/n-3 ratio = 0.

Effect of storage time, temperature, antioxidant and thawing on fatty acid composition of plasma, serum and red blood cells - A pilot biobank study.

Background: It studies on the factors that affect the stability of fatty acid profiles from human blood specimens are generally performed by evaluating the effect of a single factor on an individual fatty acid and excluding a considerable amount of data from the total fatty acid profiles.

Methods: The stability of fatty acids from plasma, serum and red blood cells (RBC) was evaluated in terms of time, temperature, antioxidant and thawing. The fatty acids were methylated and analyzed by gas chromatography.

Uptake of heavy metals and arsenic in black soldier fly (Hermetia illucens) larvae grown on seaweed-enriched media.

Background: The black soldier fly (Hermetia illucens) is one of the most promising insect species for use in animal feed. However, studies investigating feed and food safety aspects of using black soldier fly as feed are scarce. In this study, we fed black soldier fly larvae feeding media enriched with seaweed, which contains naturally high concentrations of heavy metals and arsenic.

Modulation of nutrient composition of black soldier fly (Hermetia illucens) larvae by feeding seaweed-enriched media.

Black soldier fly (Hermetia illucens) larvae are a promising source of protein and lipid for animal feeds. The nutritional composition of the BSF larvae depend partly on the composition of the feeding medium. The BSF lipid profile in part mimics the feeding media lipid profile, and micronutrients, like minerals and vitamins, can readily accumulate in black soldier fly larvae.

Short-term starvation at low temperature prior to harvest does not impact the health and acute stress response of adult Atlantic salmon.

A period of starvation is regarded as a sound practice in aquaculture prior to handling, transportation and harvest, to minimise impacts on welfare and ensure proper hygiene after harvest. However, documentation of welfare issues such as stress following starvation and handling in adult Atlantic salmon are lacking. This study aimed to examine gut emptying and potential stress during a two week starvation period, and whether this starvation period changed the tolerance for physical stress.

Lens metabolomic profiling as a tool to understand cataractogenesis in Atlantic salmon and rainbow trout reared at optimum and high temperature.

Periods of high or fluctuating seawater temperatures result in several physiological challenges for farmed salmonids, including an increased prevalence and severity of cataracts. The aim of the present study was to compare cataractogenesis in Atlantic salmon (Salmo salar L.) and rainbow trout (Oncorhynchus mykiss) reared at two temperatures, and investigate whether temperature influences lens metabolism and cataract development.

The metabolic response in fish to mildly elevated water temperature relates to species-dependent muscular concentrations of imidazole compounds and free amino acids.

Fish species show distinct differences in their muscular concentrations of imidazoles and free amino acids (FAA). This study was conducted to investigate whether metabolic response to mildly elevated water temperature (MEWT) relates to species-dependent muscular concentrations of imidazoles and FAA. Thirteen carp and 17 Nile tilapia, housed one per aquarium, were randomly assigned to either acclimation (25°C) or MEWT (30°C) for 14 days.

Antioxidant nutrition in Atlantic salmon () parr and post-smolt, fed diets with high inclusion of plant ingredients and graded levels of micronutrients and selected amino acids.

The shift from marine to plant-based ingredients in fish feeds affects the dietary concentrations and bioavailability of micronutrients, amino acids and lipids and consequently warrants a re-evaluation of dietary nutrient recommendations. In the present study, an Atlantic salmon diet high in plant ingredients was supplemented with graded levels of nutrient premix (NP), containing selected amino acids, taurine, cholesterol, vitamins and minerals. This article presents the results on the antioxidant nutrients vitamin C, E and selenium (Se), and effects on tissue redox status.

Atlantic salmon () require increased dietary levels of B-vitamins when fed diets with high inclusion of plant based ingredients.

Aiming to re-evaluate current recommendations for nutrient supplementations when Atlantic salmon are fed diets based on plant ingredients, two regression experiments, with parr and post-smolt, were conducted. A control diet was included to evaluate if ingredients supplied sufficient nutrients without any added nutrient package (NP). The nutrient package consisted of vitamins B, C, E, minerals, cholesterol, methionine, taurine and histidine.

The Association between Hair Cortisol and Self-Reported Symptoms of Depression in Pregnant Women.

Depression has been linked to an imbalance in cortisol. Until recently, cortisol has been studied by measuring concentrations at single time points in blood or saliva samples. Cortisol concentrations vary with circadian rhythm and experiences, from time point to time point.

Correction: Exploring Early Micronutrient Deficiencies in Rainbow Trout (Oncorhynchus mykiss) by Next-Generation Sequencing Technology - From Black Box to Functional Genomics.

[This corrects the article DOI: 10.1371/journal.pone.

In vitro Assessment of Hg Toxicity in Hepatocytes from Heat-Stressed Atlantic Salmon.

Global warming may alter the bioavailability of contaminants in aquatic environments. In this work, mercury (Hg) toxicity was studied in cells obtained from Atlantic salmon smolt kept at 15 °C (optimal growth temperature) for 3 months or at a stepwise increase to 20 °C (temperature-stress) during 3 months prior to cell harvest to evaluate whether acclimation temperature affects Hg toxicity. To examine possible altered dietary requirements in warmer seas, one group of fish following the stepwise temperature regimes was fed a diet spiked with antioxidants.

Fish pre-acclimation temperature only modestly affects cadmium toxicity in Atlantic salmon hepatocytes.

An emerging focus in environmental toxicology is how climate change will alter bioavailability and uptake of contaminants in organisms. Ectothermic animals unable to adjust their temperature by local migration, such as farmed fish kept in net pens, may become more vulnerable to contaminants in warmer seas. The aim of this work was to study cadmium (Cd) toxicity in cells obtained from fish acclimated to sub-optimal growth temperature.

Omega-3 and alpha-tocopherol provide more protection against contaminants in novel feeds for Atlantic salmon ( L.) than omega-6 and gamma tocopherol.

Extended use of plant ingredients in Atlantic salmon farming has increased the need for knowledge on the effects of new nutrients and contaminants in plant based feeds on fish health and nutrient-contaminant interactions. Primary Atlantic salmon hepatocytes were exposed to a mixture of PAHs and pesticides alone or in combination with the nutrients ARA, EPA, α-tocopherol, and γ-tocopherol according to a factorial design. Cells were screened for effects using xCELLigence cytotoxicity screening, NMR spectroscopy metabolomics, mass spectrometry lipidomics and RT-qPCR transcriptomics.

Functional amino acids in fish nutrition, health and welfare.

Protein is the most expensive part of fish diets and supplies amino acids (AA) for energy, growth, protein synthesis and as substrates for key metabolic pathways. Functional AA is a term used to describe AA that are involved in cellular processes apart from protein synthesis. A deficiency, or imbalance, in functional AA may impair body metabolism and homeostasis.

The mining chemical Polydadmac is cytotoxic but does not interfere with Cu-induced toxicity in Atlantic salmon hepatocytes.

To speed up sedimentation of suspended solids the mining industry often uses flocculent chemicals. In this work we evaluated the cytotoxic and mechanistic effects of Polydadmac, and its basic component Dadmac, on fish cells. Dose-response effects, temperature-dependent effects and impact of Dadmac and Polydadmac on Cu toxicity were studied in Atlantic salmon hepatocytes.

Effect of temperature and diet on wound healing in Atlantic salmon (Salmo salar L.).

Compromised skin integrity of farmed Atlantic salmon, commonly occurring under low temperature and stressful conditions, has major impacts on animal welfare and economic productivity. Even fish with minimal scale loss and minor wounds can suffer from secondary infections, causing downgrading and mortalities. Wound healing is a complex process, where water temperature and nutrition play key roles.