Present address: Ocean Sciences Center, Memorial University of Newfoundland, St John's, Newfoundland A1C 5S7, Canada.
Digestive capacities, inbreeding and growth capacities in juvenile Arctic charr Salvelinus alpinus
Article first published online: 28 JAN 2010
© 2009 The Authors. Journal compilation © 2009 The Fisheries Society of the British Isles
Journal of Fish Biology
Volume 75, Issue 10, pages 2695–2708, December 2009
How to Cite
Ditlecadet, D., Blier, P. U., Le François, N. R. and Dufresne, F. (2009), Digestive capacities, inbreeding and growth capacities in juvenile Arctic charr Salvelinus alpinus. Journal of Fish Biology, 75: 2695–2708. doi: 10.1111/j.1095-8649.2009.02468.x
- Issue published online: 28 JAN 2010
- Article first published online: 28 JAN 2010
- (Received 23 June 2008, Accepted 25 September 2009)
- growth rate;
- relatedness coefficient;
- metabolic capacities
Genetic variation in growth performance was estimated in 26 families from two commercial strains of Arctic charr Salvelinus alpinus. Physiological determinants of growth and metabolic capacities were also assessed through enzymatic assays. A relatedness coefficient was attributed to each family using parental genotypes at seven microsatellite loci. After 15 months of growth, faster growing families had significantly lower relatedness coefficients than slower growing families, suggesting their value as indicators of growth potential. Individual fish that exhibited higher trypsin activity also displayed higher growth rate, suggesting that superior protein digestion capacities can be highly advantageous at early stages. Capacities to use amino acids as expressed by glutamate dehydrogenase (GDH) activities were lower in the liver of fast-growing fish (13–20%), whereas white muscle of fast-growing fish showed higher activities than that of slow-growing fish for amino acid metabolism and aerobic capacity [22–32% increase for citrate synthase (CS), aspartate aminotransferase (AAT) and GDH]. The generally higher glycolytic capacities (PK and LDH) in white muscle of fast-growing fish indicated higher burst swimming capacities and hence better access to food.