Breeding programs on Atlantic salmon in Norway: lessons learned

An early establishment of selective breeding programs on Atlantic salmon has been crucial for the success of developing efficient and sustainable salmon farming in Norway. A national selective breeding program was initiated by AKVAFORSK at the beginning of the 1970s, by collecting fertilized eggs from more than 40 Norwegian river populations. Several private selective breeding programs were also initiated in the 1970s and 1980s. While these private programs were initiated using individual selection (i.e. massselection) to genetically improve growth, the national program was designed to gradually include all economically important traits in the breeding objective (i.e. growth, age at sexual maturation, disease resistance and quality traits) using a combined family and within-family selection strategy. Independent of which selection strategy and program design used, it is important to secure and maintain a broad genetic variation in the breeding populations to maximize selection response. It has been documented that genetically improved salmon from the national selective breeding program grow twice as fast as wild Atlantic salmon and require 25 per cent less feed, while salmon representing the private breeding programs all show an intermediate growth performance. As a result of efficient dissemination of genetically improved Atlantic salmon, the Norwegian salmon farming industry has reduced its feed costs by more than US$ 230 million per year! The national selective breeding program on Atlantic salmon was commercialized into a breeding company (AquaGen) in 1992. Five years later, several private companies and the AKVAFORSK Genetics Center (AFGC) established a second breeding company (SalmoBreed) using breeding candidates from one of the private breeding programs. These two breeding companies have similar products, but different strategies on how to organize the breeding program and to disseminate the genetically improved seed to the Norwegian salmon industry. Greater competition has increased the necessity to document the genetic gain obtained from the different programs and to market the economic benefits of farming the genetically improved breeds. Both breeding companies have organized their dissemination to get a sufficient share of the economic benefits in order to sustain and improve their breeding programs.Biotechnology, Genetics, Food fish, Genetic drift, Genetic diversity, Aquatic animals, DNA, Selective breeding, Breeding success, Research programmes Salmonidae

Breeding programs on Atlantic salmon in Norway: lessons learned

An early establishment of selective breeding programs on Atlantic salmon has been crucial for the success of developing efficient and sustainable salmon farming in Norway. A national selective breeding program was initiated by AKVAFORSK at the beginning of the 1970s, by collecting fertilized eggs from more than 40 Norwegian river populations. Several private selective breeding programs were also initiated in the 1970s and 1980s. While these private programs were initiated using individual selection (i.e. massselection) to genetically improve growth, the national program was designed to gradually include all economically important traits in the breeding objective (i.e. growth, age at sexual maturation, disease resistance and quality traits) using a combined family and within-family selection strategy. Independent of which selection strategy and program design used, it is important to secure and maintain a broad genetic variation in the breeding populations to maximize selection response. It has been documented that genetically improved salmon from the national selective breeding program grow twice as fast as wild Atlantic salmon and require 25 per cent less feed, while salmon representing the private breeding programs all show an intermediate growth performance. As a result of efficient dissemination of genetically improved Atlantic salmon, the Norwegian salmon farming industry has reduced its feed costs by more than US$ 230 million per year! The national selective breeding program on Atlantic salmon was commercialized into a breeding company (AquaGen) in 1992. Five years later, several private companies and the AKVAFORSK Genetics Center (AFGC) established a second breeding company (SalmoBreed) using breeding candidates from one of the private breeding programs. These two breeding companies have similar products, but different strategies on how to organize the breeding program and to disseminate the genetically improved seed to the Norwegian salmon industry. Greater competition has increased the necessity to document the genetic gain obtained from the different programs and to market the economic benefits of farming the genetically improved breeds. Both breeding companies have organized their dissemination to get a sufficient share of the economic benefits in order to sustain and improve their breeding programs

Digestibility in selected rainbow trout families and modelling of growth from the specific intake of digestible protein

The experiments aimed to clarify variations in digestibility of dietary nutrients in rainbow trout. Furthermore, the objective was to study how differences in digestibility might be related to growth and feed utilisation at various growth rates. When comparing the results from the experiments it appeared that particularly protein digestibility was closely related to specific growth rate and feed conversion ratio at high growth rates. As a tool to visualise the relationship between protein digestibility and growth of rainbow trout a growth model was developed based on the specific intake of digestible protein, and general assumptions on protein content and protein retention efficiency in rainbow trout. The model indicated that increased protein digestibility only partly explained growth increase and that additional factors were important for growth increment

Effects of geographic origin on growth and food intake in Eurasian perch (Perca fluviatilis L.) juveniles under intensive culture conditions

Survival, growth, and food intake of Eurasian perch (Perca fluviatilis) juveniles from different stocks originating from various geographic regions of Europe were compared under the same conditions of laboratory-scale intensive culture. In Experiment 1, four stocks originating from Italy (1), southwest (SF) and northwest (NF) France, and Belgium (B) were examined at larval and early juvenile (initial body weight, IBW = 0.53 g) stages. In Experiment 2, B stock was compared to a Finnish (F) one in two trials, including small (IBW = 1.26 g) and large (IBW = 32 g) juveniles. In Experiment 3, small (IBW = 1.29 g) and large (IBW = 7.33 g) juveniles from Polish (P), F, and B stocks were examined. In Experiment 1, body weight means at hatching and survival at the end of the larval stage were significantly lower in the I and SF stocks than in the B and NF stocks. In the early juvenile stage, survival and growth rates were significantly lower in the I and SF stocks than in the B and NF ones. In Experiment 2, {early juvenile stage} survival in the F stock was significantly lower than in the B stock, partly due to a higher incidence of cannibalism. During this stage, growth rates and food intake or feed efficiency in the F and B stocks were comparable, but at the end of the juvenile stage, the F stock outperformed the B one. In Experiment 3, survival in all the three stocks was comparable both in small and large juveniles. In contrast to the higher performance of F juveniles in Experiment 2, growth rates were comparable between the B and F stocks, and fish from the P stock had the highest growth rates. The results indicate a high level of variation within and between hatchery stocks in survival rates, growth rates, and food intake. These variations depended on the geographic origin of the fish, with the lowest survival and growth potentials being in the stocks originating from the southern regions. These findings highlight the interest in evaluating growth and food consumption of different Eurasian perch stocks. Such evaluation is a necessary tool for genetic selection in improving performance in perch aquaculture. (C) 2004 Elsevier Science B.V. All rights reserved