Project description:Stocking density is considered as a key factor determining the productivity of fish aquaculture systems. The transcriptomic response to crowding stress is, however, still poorly investigated. We aimed at the identification of potential biomarker genes via microarray analyses to get insight into molecular pathways modulated through density-induced stress in farmed rainbow trout Oncorhynchus mykiss. Transcriptome profiling in liver, kidney, and gills was complemented with behaviarol observation and analysis of classical plasma parameters. Individuals of two trout strains were exposed for eight days to definite stocking densities, 1 kg/m³ (low density); 10 kg/m³ (moderate); 18 kg/m³ (elevated); and 35 kg/m³ (high). Whereas stocking density had no significant effect on cortisol levels, plasma glucose levels were elevated in trout kept at high density. Pathway enrichment analyses confirmed the upregulation of HIF1a signaling in liver contributing to glucose homeostasis during stress conditions, while mTOR and PI3K/AKT signaling pathways were downregulated. Further perturbed hepatic pathways were involved in protein ubiquitination and the biosynthesis of cholesterol, retinol and glutathione. Three stocking density conditions were investigated: an uncrowded âmoderateâ density (MD: 10 kg trout/m³) , an elevated density (ED: 18 kg/m³ ), and high density (HD: 35 kg/m³). The experiment was performed twice with two strains of Steelhead rainbow trout (Troutlodge and Born trout), randomly assigned to identical glass tanks with MD (30 and 34 individuals), ED (60 and 64 individuals), and HD (120 and 140 individuals). Trout were sampled 8 d after experimental onset.
Project description:Stress represents a major factor negatively affecting fish welfare in aquaculture. The objective of the present study was to identify and evaluate informative indicators for the welfare of rainbow trout Oncorhynchus mykiss exposed to (A) a critical water temperature of 27 °C and (B) acute crowding of 100 kg/m3 combined with water temperature of 27 °C. In order to make an approximate assessment of the overall condition, we determined health index, spleen-somatic index and haematocrit and recorded the blood concentrations of haemoglobin, cortisol and glucose of rainbow trout under challenging versus control conditions. Moreover, we analysed the transcriptomic profiles of the spleen of the two stress-treatment and the reference groups to identify gene sets, which are specific for temperature stress alone or combined temperature and crowding stress.
Project description:Stocking density is considered as a key factor determining the productivity of fish aquaculture systems. The transcriptomic response to crowding stress is, however, still poorly investigated. We aimed at the identification of potential biomarker genes via microarray analyses to get insight into molecular pathways modulated through density-induced stress in farmed rainbow trout Oncorhynchus mykiss. Transcriptome profiling in liver, kidney, and gills was complemented with behaviarol observation and analysis of classical plasma parameters. Individuals of two trout strains were exposed for eight days to definite stocking densities, 1 kg/m³ (low density); 10 kg/m³ (moderate); 18 kg/m³ (elevated); and 35 kg/m³ (high). Whereas stocking density had no significant effect on cortisol levels, plasma glucose levels were elevated in trout kept at high density. Pathway enrichment analyses confirmed the upregulation of HIF1a signaling in liver contributing to glucose homeostasis during stress conditions, while mTOR and PI3K/AKT signaling pathways were downregulated. Further perturbed hepatic pathways were involved in protein ubiquitination and the biosynthesis of cholesterol, retinol and glutathione.
Project description:The aim of present study is to identify and quantify proteins involved in the events of fertilization and early embryo development using a label-free protein quantification method in rainbow trout (Oncorhynchus mykiss) as an economically important fish species in aquaculture.
Project description:A rapid decline in temperature poses a major challenge for poikilothermic fish. The gene expression of rainbow trout Oncorhynchus mykiss having undergone such a cold shock (0 °C) and a control (5 °C) were compared in a microarray-based study.
Project description:The hypoxia frequently occurs in natural aquatic systems and aquaculture environment due to the natural reasons and human factors such as extreme climate, high density farming, environmental pollution and global warming, which have gradually become a huge threat to aquatic ecosystem functions and aquatic organism survival, causing serious ecological damage and enormous economic losses. Rainbow trout (Oncorhynchus mykiss), as a hypoxia-sensitive fish species, is a good model to study hypoxia stress. The molecular regulation and oxidative stress of rainbow trout still remains unknown in response to environmental hypoxia and reoxygenation stress. In this study, the transcriptome and biochemical indexes of rainbow trout liver in response to hypoxia for different durations were analyzed to highlight the changes in the molecular regulation and oxidative stress.
Project description:The objective of this study was to identify and quantify proteomic profiles of intestine of rainbow trout (Oncorhynchus mykiss). Specific pathogen free rainbow trout (mean length 15 ± 1 cm) were maintained in recirculating de-chlorinated water at 19±1 °C. Prior to the experiment, fish were distributed between aquaria. The test groups were infected by immersion of Yersinia ruckeri CSF007-82 (biotype 1) and 7959-11 (biotype 2) strains. The control group was immersed similar with sterile broth medium. Fish were anaesthetized and sampled aseptically at different time points. Each intestine was washed three times with sterile phosphate-buffered saline containing a cocktail of mammalian protease inhibitors. Intestinal mucosa was scraped with a sterile large scalpel blade. Intestinal samples were snap-frozen in liquid nitrogen and stored at –80 °C.
Project description:The objective of this study was to identify and quantify proteomic profiles of spleen of rainbow trout Oncorhynchus mykiss. Specific pathogen free rainbow trout (mean length 15 ± 1 cm) were maintained in recirculating de-chlorinated water at 19±1 °C. Prior to the experiment, fish were distributed between 9 aquaria, 18 fish per aquarium. The test groups were infected by immersion of Yersinia ruckeri strains: CSF007-82 (biotype 1) and 7959-11 (biotype 2). The control group was immersed similar with sterile broth medium. There were 3 aquaria per each group (CSF007-82-infected, 7959-11-infected and control). Nine fish from infected and control fish groups were anaesthetized with MS-222 at 3, 9 and 28 days post exposure and sampled aseptically. Each spleen was washed three times with sterile phosphate-buffered saline containing a cocktail of mammalian protease inhibitors. Spleen samples were snap-frozen in liquid nitrogen and stored at –80 °C.
Project description:Rainbow trout (Oncorhynchus mykiss) is highly sensitive to high-temperature stress as an important economic cold-water fish. While previous research has concentrated on the transcriptomic to acute heat stress in rainbow trout, there remains a gap in knowledge regarding the overarching regulatory mechanisms at the translation level. In our research, we utilized a combination of transcriptomic and translatomic analyses to investigate the intricate molecular response mechanisms in the liver of rainbow trout when subjected to heat stress. Through comprehensive multi-omics analysis, we revealed the dynamic translational pattern of rainbow trout liver under heat stress for the first time. Comparative analysis of ribosome analysis data with RNA-seq data showed that the fold changes of gene expression at the transcriptional level were highly correlated (R2 = 0.83) with those at the translational level globally. In total, 2,203 genes exhibited significant alterations exclusively within the translational level. However, the limited overlap in response genes between transcription and translation under heat stress suggests that these two processes may independently modulate the cellular response to thermal challenges. Significant changes in the translation efficiency of 809 genes were observed under heat stress. Further analysis indicated that the translation efficiency of genes were strongly influenced by sequence characteristics such as GC content, coding sequence length and NMFE. Moreover, 3,468 putative uORFs were identified in 2,676 genes, which potentially modulating translation efficiency of mORFs. These findings provide a novel perspective for understanding the physiological adaptations of rainbow trout in response to changes in ambient temperature.