587 research outputs found
The effect of carotenoids on the development of roe and on growth rate of Atlantic salmon fry
Staging Cultural Identities as Political Performance: HĂĄlogaland Teater, North Norwegian stage language and the emancipation of North Norwegian identities
When Hålogaland Teater was established in Tromsø in 1970 as Norway’s first regional theatre, the main goal was to create a professional company that would act as a people’s theatre of North Norway. In order to achieve this, the underlying principle of the theatre was that they should produce plays about the North Norwegian reality using a North Norwegian stage language and that these plays should be devised in close collaboration with the local population. Initially this caused a lot of controversy because the theatre challenged accepted standards of theatre-making both in terms of content and representation. For some it was utterly inconceivable that national and international classics such as Peer Gynt and Hamlet should be performed in a low-status North Norwegian dialect. It was simply perceived to be a sign of the deterioration of the arts! Despite heated debates and major conflicts, the artistic and political principles of Hålogaland Teater remained constant and today, almost fifty years later, both Shakespeare and Ibsen are performed in North Norwegian dialect without any protests and with great success. How was this development possible? And what has it meant for the northern region and its people? These are questions that I am exploring in this article with the aid of Bourdieu's “thinking tools”. The main argument is that Hålogaland Theatre has been central in the revaluation of Northern Norwegian identities and culture by elevating the low-status Northern Norwagian dialect to the status of official stage language
Causes of variation in carcass traits of Atlantic salmon (Salmo salar)
The aim of the present study was to reveal causes of variation
in carcass traits of farmed Atlantic salmon (Salmo salar). During slaughtering of one year class Atlantic salmon,
composed of half sib and full sib groups, samples for
determination of carotenoid levels in flesh and ovaries were
collected. Also the hepatosomatic and viscerosomatic indexes
as well as relative visceral fat content were determined. As expected it was found that these traits were influenced by
several factors. The material is too limited for firm
conclusions, but evidently the carotenoid level depends largely on stage of maturity and possibly also on genetic factors. Genetic factors seem to influence the visceral fat
content. In hepatosomatic and visceral indexes, and possibly
in visceral fat content, a strange and still unexplained interaction between sex and stage of maturation was observed
Wild salmon should not be threatened by healthy and non-genetically manipulated escapees
Rungruangsak-Torrissen K. Cultured salmon as escapees should never threaten salmon stocks in the wild as long as they are healthy and are not genetically manipulated. By studying a key digestive protease, trypsin, which is sensitive to environmental changes and influences on food utilisation and growth during the whole life cycle of Atlantic salmon, it is indicated that changes in the phenotypic expression of trypsin can be induced by temperature during egg incubation and the start-feeding period of the alevins. In addition, Atlantic salmon with the same trypsin phenotype showed different feed conversion efficiency and growth rate at different temperatures. Trypsin genes seem to be stable, and although the pattern of expressed genes varies extensively, the expression of trypsinogen mRNA is quantitatively similar between individual salmon in line with the observation that the total trypsin specific activity was similar between the fish with different trypsin phenotypes. However the luminal secretion of the active enzyme, and probably the relative amounts of trypsin isozymes, could be modified by water temperature and food quality. These results indicate that changes in the environmental condition can influence gene expressions of the fish at DNA, RNA and protein levels, regardless of genetic expression of parents. This means that whether the escapees or wild fish is the spawning population, an incidence of the offsprings to have their gene expressions adapted to that environment will be similar. It is the environmental condition that has to be conserved in order to control the genetic structure of animals in the wild. It is naive to think that genetically manipulated escapees such as triploid salmon will not have any impact on wild population, as they are not fertile. Under a more favourable condition for growth, triploid escapees could compete with wild fish on food availability as they have higher consumption rates for higher growth rates, unlike ordinary diploid salmon that could have better food utilisation at a similar consumption rate. This may cause a higher survival rate in triploid escapees and if they spawn, hatching success and survival rate of the offsprings will be low due to low gamete quality for reproduction in triploid fish. This could result in a smaller population of the new generation in that environment in the wild.Wild salmon should not be threatened by healthy and non-genetically manipulated escapeesacceptedVersio
The effect of carotenoids on the development of roe and on growth rate of Atlantic salmon fry
Forbedring av avlsstammer for Atlantisk laks ved bruk av gener som koder for trypsin-like isozymer
Sluttrapport NFR/NFFR- nr. 1402 - 701.30
Neural computational model GrowthEstimate: A model for studying living resources through digestive efficiency
Neural computational model GrowthEstimate: A model for studying living resources through digestive efficiencyThe neural computational model GrowthEstimate is introduced with focusing on new perspectives for the practical estimation of weight specific growth rate (SGR, % day–1). It is developed using recurrent neural networks of reservoir computing type, for estimating SGR based on the known data of three key biological factors relating to growth. These factors are: (1) weight (g) for specifying the age of the growth stage; (2) digestive efficiency through the pyloric caecal activity ratio of trypsin to chymotrypsin (T/C ratio) for specifying genetic differences in food utilization and growth potential, basically resulting from food consumption under variations in food quality and environmental conditions; and (3) protein growth efficiency through the condition factor (CF, 100 × g cm–3), as higher dietary protein level affecting higher skeletal growth (length) and resulting in lower CF. The computational model was trained using four datasets of different salmonids with size variations. It was evaluated with 15% of each dataset, resulting in an acceptable range of SGR outputs. Additional tests with different species indicated similarity between the estimated SGR outputs and the real SGR values, and the same ranking of wild population growth. The developed model GrowthEstimate is exceptionally useful for the precise and comparable growth estimation of living resources at individual levels, especially in natural ecosystems where the studied individuals, environmental conditions, food availability and consumption rates cannot be controlled. It is a revelation and will help to minimize uncertainty in wild stock assessment process. This will improve our knowledge in nutritional ecology, through the biochemical effects of climate change and environmental impact on the growth performance quality of aquatic living resources in the wild, as well as in aquaculture. The original GrowthEstimate software is available at GitHub repository (https://github.com/RungruangsakTorrissenManoonpong/GrowthEstimate). All other relevant data are within the paper. It will be improved for generality for future use, and required co-operations of the biodata collections of different species from different climate zones. Therefore, a co-operation will be available.publishedVersio
Artificial hatching substrate and different time of transfer to startfeeding: Effect on growth and protease activities of the Atlantic salmon (Salmo salar).
Groups of Atlantic salmon (Salmo salar) eggs were hatched in a Californian hatching system with and without an astro-turf artificial substrate, and food was presented at four different points in development. Dry weight development and protease activities were studied. Irrespective of time of transfer the astro-turf reared fry were bigger than the flat
screen reared fry at the termination of the experiment. In
respect of growth the first and the fourth transfers were
clearly suboptimal for the fry from both systems
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