Project description:This study was performed to investigate assess the impacts of CO and/or CM containing diets on Atlantic salmon hepatic gene expression in order to identify candidate molecular biomarkers of responses to camelina-containing diets. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial (Control diet: FO; Test diet: 100% FO replacement with CO, with solvent-extracted FM and inclusion of 10% CM (100COSEFM10CM). A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to FO controls at week 16.
Project description:The present work studies the effect of Debaryomyces hansenii yeast-based products on physiological responses in Atlantic salmon exposed to a short-term stress. For this, a control fishmeal-based diet (CD) and experimental diets containing 0.1% of Debaryomyces hansenii were fed to fish for 8 weeks in fresh water. At the end of the feeding experiment, fish were exposed to 1-minute hypoxia stress and samples were collected post-stress
Project description:The objective of the current study was to examine the effects of yeasts on intestinal health and transcriptomic profile of Atlantic salmon fed SBM-based diets in seawater. Cyberlindnera jadinii (CJ) and Wickerhamomyces anomalus (WA) yeasts were produced in-house and processed by direct heat-inactivation with spray-drying (ICJ and IWA) or autolyzed at 50 ºC for 16 h (ACJ and AWA), followed by spray-drying. Six diets were formulated, one based on fishmeal (FM), a challenging diet with 30% soybean meal (SBM) and four other diets containing 30% SBM and 10% of each of the four yeast fractions (i.e., ICJ, ACJ, IWA and AWA). The results showed that the inclusion of CJ yeasts reduced loss of supranuclear vacuolization, along with reduction in population of CD8α positive cells present in the lamina propria of fish fed the SBM diet. The CJ yeasts controlled the inflammatory profile of fish fed SBM through up-regulation of pathways related to wound healing and taurine metabolism. Additionally, the WA yeasts dampened the inflammatory profile of fish fed SBM through down-regulation of pathways related to toll-like receptor signaling, C-lectin receptor, cytokine receptor and signal transduction. The results suggest that yeasts could be used as protein ingredients with functional properties in diets for Atlantic salmon.
Project description:The optimal dietary requirement of omega-3 long-chain polyunsaturated fatty acids (ω3 LC-PUFA), namely docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), for Atlantic salmon that promotes optimal growth and health warrants careful investigation. We used 44K microarrays to study the influence of increasing levels of dietary DHA + EPA (0, 1.0 and 1.4% of the diet, as formulated) in the presence of high linoleic acid (LA) on Atlantic salmon growth and liver transcriptome. After a 14-week feeding trial, Atlantic salmon fed diet ω3LC0 (i.e. 0% of DHA + EPA) showed significantly lower final weight and weight gain, and higher feed conversion ratio compared with ω3LC1.0 and ω3LC1.4 diet groups. The microarray experiment identified 55 and 77 differentially expressed probes (Rank Products analyses; PFP < 10%) in salmon fed diets ω3LC1.4 and ω3LC1.0 compared with those fed diet ω3LC0, respectively. The comparison between ω3LC1.4 and ω3LC1.0 revealed 134 differentially expressed probes.
Project description:This study was performed to investigate assess the impacts of CO and/or CM containing diets on Atlantic salmon hepatic gene expression in order to identify candidate molecular biomarkers of responses to camelina-containing diets. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial (Control diet: FO; Test diet: 100% FO replacement with CO, with solvent-extracted FM and inclusion of 10% CM (100COSEFM10CM). A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to FO controls at week 16. Atlantic salmon were fed for 16 weeks with the FO or 100COSEFM10CM diet (three tanks per diet). Liver samples were taken from 7 fish from each tank at week 16. A universal reference design was used for the microarray experiment. For the test samples, RNA was used from individual livers of fish from the 2 treatment groups: FO and 100COSEFM10CM. For each treatment group we used 9 biological replicates (3 fish from each of 3 tanks). All test samples were labeled with Cy5. The common reference was a pool of 18 RNA samples from livers of fish from all individuals invovled in microarray experiment. The common reference was labeled with Cy3. Each individual test sample was hybridized together with the common reference sample on an array, so the experiment consisted of 18 arrays
Project description:Background: Commercial Atlantic salmon is fed diets with high fat levels to promote fast and cost-effective growth. To avoid negative impact of obesity, food additives that stimulate fat metabolism and immune function are of high interest. TTA, tetradecylthioacetic acid, is a synthetic fatty acid that stimulates mitochondrial β -oxidation most likely by activation of peroxysome proliferator-activated receptors (PPARs). PPARs are important transcription factors regulating multiple functions including fat metabolism and immune responses. Atlantic salmon experiments have shown that TTA supplemented diets significantly reduce mortality during natural outbreaks of viral diseases, suggesting a modulatory role of the immune system. Results: To gain new insights into TTA effects on the Atlantic salmon immune system, a factorial, high-throughput microarray experiment was conducted using a 44K oligo nucleotide salmon microarray SIQ2.0 and the Atlantic salmon macrophage-like cell line ASK. The experiment was used to determine the transcriptional effects of TTA, the effects of TTA in poly(I:C) elicited cells and the effects of pretreating the cells with TTA. The expression patterns revealed that a large proportion of genes regulated by TTA were related to lipid metabolism and increased mitochondrial β -oxidation. In addition we found that for a subset of genes TTA antagonized the transcriptional effects of poly(I:C). This, together with the results from qRT-PCR showing an increased transcription of anti-inflammatory IL10 by TTA, indicates anti-inflammatory effects. Conclusions: We demonstrate that TTA has significant effects on macrophage-like salmon cells that are challenged by the artificial dsRNA poly(I:C). The immune stimulatory effect of TTA in macrophages involves increased lipid metabolism and suppressed inflammatory status. Thus, suggesting that TTA directs the macrophage-like cells towards alternative, anti-inflammatory, activation. This has positive implications for TTA as a feed additive.
Project description:The effect of different diets (i.e. fish oil based vs vegetable oil based) on liver transcription profiles over the life history stages (freshwater and marine phases) of cultured Atlantic salmon (Salmo salar) were explored. Two groups of fish were raised from first feeding on different lipid containing diets; a) the standard 100% fish oil based diet, the other enriched with a blend of vegetable oils (75%) + fish oil (25%). Liver samples were taken from fish at four time points: two freshwater phase (as parr 36 weeks post hatch (wph); as pre-smolts, 52 wph) and two marine phase ( as post-smolts 55 wph; and as adult fish , 86 wph). A total of 96 cDNA microarray hybridisations - TRAITS / SGP Atlantic salmon 17k feature cDNA microarray - were performed ( 2 diets x 4 time points x 6 biological replicates x 2 -dye swap) using a comon pooled reference contol design.
Project description:Fish were fed a standard fish meal (FM) diet or a diet with partial replacement of FM with solvent extracted camelina meal (CM) (8%, 16% or 24% CM inclusion) during a 16-week feeding trial. A significant decrease in growth performance was seen in fish fed the CM inclusion diets. A 44k oligonucleotide array experiment was used to identify any differentially expressed transcripts in the distal intestine of the fish fed the 24% CM diet compared to the control. The expression level of these genes was validated using quantitative polymerase chain reaction, which was also used to measure transcript expression in the fish fed the 8% CM and 16% CM diets. Histopathological analysis was used to quantify any physical signs in inflammation in the distal intestine of the Atlantic salmon fed the CM-containing diets.
Project description:In this experiment, we used four diets, one based on FM, a challenging diet with 40% soybean meal (SBM), and two diets containing 40% SBM with 5% of Cyberlindnera jadinii yeast exposed to different down-stream processing conditions (heat-inactivated or autolysation). The immunomodulatory effects of the diets were analyzed in the spleen of Atlantic salmon after 37 days of feeding. The results showed that the inclusion of autolysed C. jadinii (ACJ) was able to modulate the response of Atlantic salmon compared to fish fed the SBM-diet, through the activation of biological pathways related to endocytosis, PPRs-signal transduction and transporter activity. Finally, we suggest that the spleen is a good candidate to characterize the immunomodulatory effects of functional ingredients in Atlantic salmon.