Project description:Infectious diseases among fish present an important economic burden for the aquaculture and fisheries industries around the world. For example, the infectious salmon anemia virus (ISAV) is known to infect farmed Atlantic salmon (Salmo salar), and results in millions of dollars of lost revenue to salmon farmers. Although improved management and husbandry practices over the last few years have minimized the losses and the number of outbreaks, the risk of new virulent isolates emerging is still a looming threat to the viability and sustainability of this industry. An understanding of the host-pathogen interactions at the molecular level during the course of an infection thus remains of strategic importance for the development of molecular tools and efficient vaccines capable of minimizing losses in the eventual case of a new outbreak. Using a 32 k cDNA microarray platform (cGRASP), we have studied various signaling pathways and immune regulated genes, activated or repressed, in Atlantic salmon head-kidney during the course of an ISAV infection. Gene expressions were measured at 5 different time-points: 6h, 24h, 3d, 7d and 16d post infection to get an overall view of changes as they occurred in time. The earliest time points showed only a few differentially expressed genes in infected fish, relative to controls, although as time progressed, many additional genes involved in key defense pathways were up-regulated including MHC type I, beta-2 microglobulin, TRIM 25 and CC-chemokine 19. During the latest stage of the infection process, many genes related to oxygen transportation were under-expressed, which correlates well with the anemia observed prior to death in Atlantic salmon infected with virulent strains of ISAV. Atlantic salmon smolts from 2 families of Atlantic salmon were IP injected with either 0.1mL of 10e5 TCID50 mL-1 of virus or 0.1mL of sham solution (L15 culture medium) and divided equally in four 1000 L tanks: 2 duplicate tanks containing ISAV injected fish and 2 duplicate control tanks containing sham solution injected fish. Four fish per family were sampled immediately prior to injection. An additional two fish per family per tank (four fish per family total) were sampled at 6h, 24h, 3d, 7d and 16d post injection. Head-kidney was dissected from each fish and used for microarray analysis. ISAV infected Atlantic salmon were compared to non-infected Atlantic salmon for each time-point.
Project description:The present work characterizes the response of co-habited Atlantic (Salmo salar), chum (Oncorhynchus keta) and pink salmon (Oncorhynchus gorbuscha) to sea lice infections. Atlantic and pink salmon anterior kidney samples were profiled at three time points over nine days after the start of an experimental infection. Chum salmon anterior kidney was profiled at day six post infection only. All three species were also profiled at six days post exposure for skin responses of the pectoral fin, typically associated with lice infection.
Project description:The present study aimed to identify the persistent molecular changes occurring in Atlantic Salmon salmon (Salmo salar) eggs after 24h exposure to high concentrations (5000 mg/L) of road salt at fertilization.
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:Infectious diseases among fish present an important economic burden for the aquaculture and fisheries industries around the world. For example, the infectious salmon anemia virus (ISAV) is known to infect farmed Atlantic salmon (Salmo salar), and results in millions of dollars of lost revenue to salmon farmers. Although improved management and husbandry practices over the last few years have minimized the losses and the number of outbreaks, the risk of new virulent isolates emerging is still a looming threat to the viability and sustainability of this industry. An understanding of the host-pathogen interactions at the molecular level during the course of an infection thus remains of strategic importance for the development of molecular tools and efficient vaccines capable of minimizing losses in the eventual case of a new outbreak. Using a 32 k cDNA microarray platform (cGRASP), we have studied various signaling pathways and immune regulated genes, activated or repressed, in Atlantic salmon head-kidney during the course of an ISAV infection. Gene expressions were measured at 5 different time-points: 6h, 24h, 3d, 7d and 16d post infection to get an overall view of changes as they occurred in time. The earliest time points showed only a few differentially expressed genes in infected fish, relative to controls, although as time progressed, many additional genes involved in key defense pathways were up-regulated including MHC type I, beta-2 microglobulin, TRIM 25 and CC-chemokine 19. During the latest stage of the infection process, many genes related to oxygen transportation were under-expressed, which correlates well with the anemia observed prior to death in Atlantic salmon infected with virulent strains of ISAV.
Project description:Head kidney (HK) and distal intestine (DI) from Atlantic salmon (average 550g) were collected. Immune cells from DI and HK were extracted and grown at 12°C in Leibovitz’s L-15 Medium (L-15). The isolated DI or HK leukocytes were allowed to adhere on a petri dish with 2 mL L-15+ for 2 days at 12°C. After removing the supernatant containing non-adherent cells, the adherent cells on petri dish were detached by washing three times with 1.5 mL ice-cold PBS supplemented with 5 mM EDTA. The cells were centrifuged (500 × g, 5 min, 4°C) and re-suspended with 2 mL L-15+. Total RNA was extracted from adherent cells from HK or DI (< 500,000 cells). To understand the miRNA expression profiles of adherent intestinal cells (AICs) and to compare them with those of adherent head kidney cells (AKCs), twelve libraries (6 for AIC and 6 for AKC) were prepared. Small RNA-sequencing revealed 37 differentially expressed miRNAs; 20 were up-regulated and 17 were down-regulated. Of them, 12 miRNAs in AIC were found to be involved in regulating macrophage functions.