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 a typical cold-water fish, the development of rainbow trout aquaculture was severely hampered via the high temperature in summer. Understanding the regulatory mechanism of rainbow trout response to chronic heat stress can provide a theoretical basis for formulating measures to relieve heat stress. In the study, changes in the biochemical parameters revealed that a strong stress response occurred in rainbow trout at 24 °C, the organisms stress defense system was activated, and the immune system was also affected. Proteome of rainbow trout liver tissues under heat stress (24 °C) and control conditions (18 °C) were performed using DIA/SWATH. A total of 390 DEPs were identified by strict threshold (q-value <0.05 and fold changes >1.5), among them 175 were up-regulated and 225 were down-regulated. Some proteins related to HSP, metabolism and immunity were identified. GO analysis showed that some proteins that were highly induced to express at high temperature were involved in the regulation of cell homeostasis, metabolism, adaptive stress and stimulation. KEGG analysis shows that some pathways play an important role in the regulation of heat stress, such as metabolic pathway, protein processing in endoplasmic reticulum pathway, PPAR signaling pathway and complement and coagulation cascades pathway, etc. PPI network analysis shows HSP90b1 and C3 maybe cooperative to protect the integrity of cell membrane function under heat stress. Our finding provide a comprehensive review of protein expression of rainbow trout liver under heat stress, which helps to formulate strategies for rainbow trout to relieve heat stress during high temperature in summer.