The project is off to a good start. Results from experiments with clonal Atlantic salmon were recently presented at the AQUA 2024 conference in Copenhagen, and a scientific article about physiology and morphology in clonal Atlantic salmon will soon be submitted for publication. Another scientific article have already been submitted for publication in August 2024 (currently under review), and is about physiology and morphology in fast and slow growing Atlantic salmon. Additionally, new equipment has been acquired, specifically respirometry systems for larger sized salmon. Here, a smaller experiment has recently been completed and the data obtained will be presented at HAVBRUK2024 in Tromsø in October 2024, and a paper is currently in prep. Further experiments are already planned in detail for autumn 2024 and first half of 2025. These will focus on effects of acclimation temperature, acute thermal and hypoxia tolerances, oxygen uptake rates, and morphology in hearts and gills across different sizes of Atlantic salmon. Moreover, salmon with wild, domesticated, and hybrid genotypes have been produced in Matre. These are expected to be used in experiments either in late 2025 or 2026 once they have reached an appropriate size.
This project for young research talents seeks to decipher the cause for variation in functional phenotypic traits of Atlantic salmon using experimental biology based on ecophysiological principles. Farmed salmon have been selectively bred for 50 years with a strong focus on growth performance which may have led to negative trade-offs with other key health related traits. In parallel, conservation concerns with wild populations exists owing to escaped farm fish interbreeding in nature, which may introduce inferior genotypes and thus hurt the natural fitness of wild salmon. However, owing to the tremendous capacity for phenotypic plasticity in fish, it remains unclear how different wild and domesticated salmon actually are from each other when considering environmental effects.
Here, different genotypes will be studied in different environmental contexts with a dedicated focus on resultant functional phenotypes as assessed through physiological, morphological and immunological measurements.
Wild caught salmon will be compared to hatchery reared counterparts of both domesticated and wild genetic origin. Moreover, clonal salmon lines using both heterozygous, homozygous and triploid variants will be used as a novel model to study phenotypic variation while genotypes remain constant. Different feeding regimes and incubation temperatures will be used to manipulate growth and development rates, while acclimation studies to thermal extremes will be used to compare climate resilience between wild and farmed salmon.
Physiological performance traits will be measured and include aerobic scopes, swimming capacities, hypoxia response, and thermal tolerance. Parasite tolerance and immunological responses to Lepeophtheirus salmonis in different genotypes will be assessed. Furthermore, functional cardiac morphology as influenced by genotype and development rates across life-stages will be analyzed along with the occurrences of vertebral and otolith deformities.