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Genetic parameters and response to selection for growth in tambaqui
E C Campos1,2, C A L Oliveira1,3, F C T Araújo1,2
1PeixeGen Research Group - Management, Breeding and Molecular Genetics of Freshwater Fish, Department of Animal Science, State University of Maringá, Avenida Colombo 5790, Maringá, Paraná, Brazil.
Animal : an International Journal of Animal Bioscience
|March 21, 2020
Summary
Breeding values for tambaqui (Colossoma macropomum) growth traits can be estimated and used for selection as early as 6 months after tagging. This approach can lead to significant genetic gains in growth, with potential improvements ranging from 8% to 31%.
Area of Science:
- Aquaculture
- Animal Genetics
- Fish Breeding
Background:
- Tambaqui (Colossoma macropomum) is Brazil's most cultivated native fish.
- Breeding values for growth traits are underutilized in commercial fingerling production.
- Accurate selection is crucial for improving tambaqui aquaculture efficiency.
Purpose of the Study:
- Estimate (co)variance components for tambaqui growth traits.
- Determine optimal age for selection in breeding programs.
- Assess potential genetic gains from selection.
Main Methods:
- Measured body weight, length, and width of 2500 tambaqui at tagging, 6, and 12 months.
- Estimated heritability and common full-sib effects.
- Analyzed genetic correlations between growth traits.
- Simulated sex ratios considering sexual dimorphism.
Main Results:
- Heritability estimates for growth traits were low at tagging (0.10-0.19) but moderate to high at 6 and 12 months (0.23-0.81).
- Common full-sib effects were significant at tagging but diminished by 12 months.
- Positive genetic correlations among growth traits at 6 and 12 months were high (0.80-0.99).
- Expected genetic gains ranged from 8% to 31%.
Conclusions:
- Selection for growth traits in tambaqui is feasible and effective at 6 months post-tagging.
- Accurate heritability estimates require accounting for sex ratio, especially in heavier individuals.
- Developing early-stage sex determination tools could further enhance selection response in tambaqui aquaculture.
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