Block 1. Endocrinology of feed intake and flesh quality (25.UGOT, 20.USTAN, month 0-60)
Elucidates how feed intake mediates effects on lipid mobilization and protein accretion, and thus flesh quality traits, through ghrelin stimulation of the GH-secretagogue receptor and subsequent activation of the GH-IGF-I axis, including muscle expression of the IGF-I gene.
Block 2. Genetics of muscle quality traits (20.USTAN, 1.DIFRES, month 0-18)
Encompasses cloning of genes known to be important for flesh quality traits (firm texture, low gaping, enhanced storage and processing characteristics), and the identification of quality trait variation among natural populations of cod by reviewing the literature and linking this variation to candidate genes by searching the Fugu genomic database.
Block 3. Immunology of myogenic cell markers (20.USTAN, 66.JSF, 70.AGA, month 19-36)
Includes production of specific antibodies against myogenic cell markers (e.g. MNF, Pax 7, CD34, Myf-5) and validation of analytical methods developed in salmon for use in cod and halibut.
Block 4. Water-soluble feed components for improved flesh quality (2. NIFA, 25.UGOT, 69.BIOMAR, month 0-60)
Will focus on water soluble components with potential health promoting effect (taurine, anserine, carnosine) and feed components relevant for good taste (free amino acids and nucleotides) by feeding experiments with rainbow trout.
Block 5. Natural variation in quality-related genes (1.DIFRES, 20.USTAN, 25.UGOT, month 6-60)
Will study the genetic variation at identified candidate loci for quality in natural populations and compare that to a background of neutral genetic (microsatellite) variation, including the myostatin gene that influences both muscle density and fibre number, and the GH gene that affects both lipid and protein metabolism.
Block 6. Heritability of quantitative trait loci for flesh quality (1.DIFRES, 70.AGA, month 19-60)
Will be to estimate the heritability of QTL (quantitative trait loci) for quality traits shown to vary in natural populations.
Block 7. Integrated approach to flesh quality traits (20.USTAN, 25.UGOT, 66.JSF, 70.AGA, month 36-60)
Will exploit the novel methodologies established through blocks 1, 2, and 3 to investigate the relationship between FNmax (an important growth and quality trait), the density of muscle stem cells, including the relationship between the biological properties of muscle and flesh quality traits, as well as activity of the ghrelin-GH-IGF-I system in different populations, including comparisons between wild and farmed fish.