Project description:ISAV is one of the most dangerous pathogens causing high mortality of farmed Atlantic salmon. In this study, transcriptome responses to the virus were examined in vitro in Atlantic salmon head kidney cells culture (ASK). Poly(I:C), synthetic double-stranded RNA stimulating antiviral responses was used as a positive control.
Project description:Comparison of two single cell transcriptomic approaches to investigate cellular heterogeneity within the head kidney of healthy farmed Atlantic salmon (Salmo salar)
Project description:RNA-seq expression data from 6 libraries in Caligus rogercresseyi RNA from pooled samples from farmed Atlantic salmon was extracted by mixer-mill (Retsch) homogenization in Trizol (Invitrogen), followed by column clean-up using the RNeasy kit (QIAGEN)
Project description:Unintentional use of mold-infested plant-based feed ingredients are sources of mycotoxins in fish feeds. The presence of the emerging mycotoxins ENNB and BEA in Norwegian commercial fish feeds and plant-based feed ingredients has raised concerns regarding the health effects on farmed Atlantic salmon (Salmon salar). Atlantic salmon pre-smolts were exposed to a non-lethal single-dose of BEA and ENNB, and total RNA sequencing of the intestine and liver was carried out to evaluate gut health and identify possible hepatological changes after a single-dose dietary exposure. ENNB and BEA did not give acute toxicity, however ENNB caused the onset of pathways linked to acute intestinal inflammation and BEA exposures caused the onset of hepatic hematological disruption. The prevalence and concentration of ENNB found in today's commercial feed could affect the fish health if consumed over a longer time-period.
Project description:Norway is the largest producer and exporter of farmed Atlantic salmon (Salmo salar) worldwide. Skin disorders correlated with bacterial infections represent an important challenge for fish farmers due to the economic losses caused. Little is known about this topic, thus studying the skin-mucus of Salmo salar and its bacterial community depict a step forward in understanding fish welfare in aquaculture. In this study, we used label free quantitative mass spectrometry to investigate the skin-mucus proteins associated with both Atlantic salmon and bacteria. In addition, the microbial temporal proteome dynamics during 9 days of mucus incubation with sterilized seawater was investigated, in order to evaluate their capacity to utilize mucus components for growth in this environment.
Project description:Fish gills are not only the respiratory organ, but also essential for ion-regulation, acid-base control, detoxification, waste excretion and host defense. Multifactorial gill diseases are common in farmed Atlantic salmon, and still poorly understood. Understanding gill pathophysiology is of paramount importance, but the sacrifice of large numbers of experimental animals for this purpose should be avoided. Therefore, in vitro models, such as cell lines, are urgently required to replace fish trials. An Atlantic salmon gill epithelial cell line, ASG-10, was established at the Norwegian Veterinary institute in 2018. This cell line forms a monolayer expressing cytokeratin, e-cadherin and desmosomes, hallmarks of a functional epithelial barrier. To determine the value of ASG-10 for comparative studies of gill functions, the characterization of ASG-10 was taken one step further by performing functional assays and comparing the cell proteome and transcriptome with those of gills from juvenile freshwater Atlantic salmon. The ASG-10 cell line appear to be a homogenous cell line consisting of epithelial cells, which express tight junction proteins. We demonstrated that ASG-10 forms a barrier, both alone and in co-culture with the Atlantic salmon gill fibroblast cell line ASG- 13. ASG-10 cells can phagocytose and express several ATP-binding cassette transport proteins. Additionally, ASG-10 expresses genes involved in biotransformation of xenobiotics and immune responses. Taken together, this study provides an overview of functions that can be studied using ASG-10, which will be an important contribution to in vitro gill epithelial research of Atlantic salmon.
Project description:Moritella viscosa is a bacterial pathogen causing winter-ulcer disease in Atlantic salmon. The lesions on affected fish lead to increased mortality, decreased fish welfare, and inferior meat quality in farmed salmon. MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional regulation by guiding the miRNA induced silencing complex to specific mRNA transcripts (target genes). The goal of this study was to identify miRNAs responding to Moritella viscosa in salmon by investigating miRNA expression in head-kidney and the muscle/skin from lesion sites caused by the pathogen. Protein coding gene expression was investigated by microarray analysis in the same materials.
Project description:Due to multi-generation domestication selection, farmed and wild Atlantic salmon diverge genetically, which raises concerns about potential genetic interactions among escaped farmed and wild populations and disrupts local adaptation through introgression. When farmed strains of distant geographic origin are used, it is unknown whether the genetic risks posed by escaped farmed fish will be greater than if more locally derived strains are used. Quantifying gene expression differences among divergent farmed, wild and F1 hybrids under controlled conditions is one of the ways to explore the consequences of hybridization. We compared the transcriptomes of late sac fry of a European (EO) farmed (“StofnFiskur”, Norwegian strain), a North American (NA) farmed (Saint John River, NB strain), a Newfoundland (NF) wild population with EO ancestry, and related F1 hybrids using 44K microarrays. Our findings indicate that the wild population showed greater transcriptome differences from the EO farmed strain than that of the NA farmed strain. We also found the largest differences in global gene expression between the two farmed strains. We detected fewer differentially expressed transcripts between F1 hybrids and domesticated/wild maternal strains. We also found that the differentially expressed genes between cross types over-represented GO terms associated with metabolism, development, growth, immune response, and redox homeostasis processes. These findings suggest that the interbreeding of escaped EO/NA farmed and NF wild population would alter gene transcription, and the consequences of hybridization would be greater from escaped EO farmed than NA farmed salmon, resulting in potential effects on the fitness of wild populations.
Project description:Marine farmed Atlantic salmon (Salmo salar) are repeatedly susceptible to amoebic gill disease (AGD) caused by the ectoparasite Neoparamoeba perurans over their life cycle. The parasite elicits a highly localized response within the gill epithelium mucosa resulting in multifocal mucoid patches at the site of parasite attachment. This host-pathogen response drives a complex immune reaction within the pathology of the disease, which remains poorly understood. A dual RNA-seq approach was employed using Illumina sequencing technology to investigate both the linteraction between the host and the parasite.
Project description:Farmed and wild Atlantic salmon was given either vegetable oil (low DHA and EPA) feed or fish oil (high in DHA and EPA) feed or phospholipid (high in phospholipid) feed from start of feeding. We sampled and RNAseq two tissues (pyloric caeca and liver) on day 0, day 48, day 65 and day 94 after initial feeding.