Disinfection by ozonation of sea-water may reduce the risk of transmission of nodavirus, a major fish pathogen, via Atlantic halibut Hippoglossus hippoglossus eggs. In the present study, eggs at 4 d prior to hatching were exposed to nodavirus and then to ozonated sea-water using different concentrations (0.3 to 10 mg l-1) and exposure times (0.5 to 10 min). None of the larvae from virus-exposed...

The present study shows that differences in pathogenicity exist among fish nodavirus strains. In challenge trials, a Japanese strain (SJ93Nag) was highly virulent to larvae of the striped jack Pseudocaranx dentex but replication was not detected in larvae of Atlantic halibut Hippoglossus hippoglossus at 6 degrees C. Conversely, a Norwegian nodavirus strain (AH95NorA) that was highly virulent to...

During the past 12 years fishery managers responsible for federal fisheries off Alaska have developed and implemented three new fishery management limited access/quota share programs in place of traditional open access management. The three limited access programs are unique but each provides for the allocation of quota shares to individual participants in the halibut and sablefish longline fis...

bstract. The fish leech Johanssonia arctica (Johansson, 1898) was collected from king crabs Paralithodes camtschaticus Tilesius, 1815) in Finnmark, N Norway, and allowed to feed on experimental fish hosts in the laboratory. This leech ingested lood from laboratory-reared cod (Gadus morhua) and halibut (Hippoglossus hippoglossus). Some experimental halibut acquired rypanosome infection, with par...

Detailed mass balance food web models were constructed to compare ecosystem characteristics for three Alaska regions: the eastern Bering Sea (EBS), the Gulf of Alaska (GOA), and the Aleutian Islands (AI). This paper documents the methods and data used to construct the models and compares ecosystem structure and indicators across models. The common modeling framework, including biomass pool and ...

Christos Palaiokostas Institute of Aquaculture i Abstract The aim of the current thesis was the analysis of the genetics of sex determination of farmed fish with sexual dimorphism, using Next Generation Sequencing. Three different species of farmed fish with sex-determining systems of varying complexity were studied. Both full-sibs and more distantly related specimens of Atlantic halibut (Hippo...

In farms, Atlantic halibut (Hippoglossus hippoglossus) exhibit low appetite to formulated feeds, resulting in slow growth rate and feed wastage. Addition of attractants and/or stimulants in feeds may motivate them to actively feed in optimum quantities. In this study, olfactory and gustatory (facial) nerve responses to some feed-related chemical compounds were recorded. The olfactory thresholds...

Fecundity in several fish species is subject to down-regulation by atresia so if fecundity is estimated many months before spawning, this will be an overestimation of the realised fecundity (actual number of eggs spawned). In order to get accurate measurements of fecundity it is important to have knowledge on when potential fecundity (estimated fecundity at time of sampling) closely resembles t...

The Northeast Fisheries Science Center’s (NEFSC) stock assessments have historically assumed that the landings reported in the dealer weighout database represent a census of total United States (US) landings. In 2009, individual fishermen reviewing the National Marine Fisheries Service’s (NMFS) records of vessel groundfish landing histories reported discrepancies between the NMFS record and the...