Well-functioning fish seed systems are crucial for human nutrition and improved livelihoods. Yet fish seed systems have received considerably little attention in the diffusion process for genetically improved strains. This study examined how seed systems of genetically improved fish strains function, assessed constraints faced, and explored entry-points to increased diffusion. To address these objectives, the study combined the seed systems performance assessment framework with innovation systems thinking.
The 2019 Annual Report outlines the CGIAR Research Program on Fish Agri-Food Systems (FISH) achievements in delivering evidence-based solutions that address the complex challenges and opportunities in fish agri-food systems in the developing world. Three years into the Program, FISH research is having a positive impact on the lives of people who depend on fisheries and aquaculture in global food systems.
The Convention on Biological Diversity provides a framework for countries to implement laws regulating the access, use and exchange of genetic resources, including how users and providers share the benefits from their use. While the international community has been preoccupied with resolving the unintended effects of access and benefit sharing (ABS) on domestication in agriculture for the past 25 years, its far-reaching consequences for global aquaculture has only recently dawned on policymakers, aquaculture producers and researchers.
Phenotypic and genetic parameters were estimated for three body traits (harvest weight, carapace length and standard length) and for adult male morphotypes of the giant freshwater prawn Macrobrachium rosenbergii in a fully pedigreed synthetic population in India. The data set included 9,173 progeny produced over four generations from 162 sires and 234 dams. Variance components and genetic parameters were estimated fitting an animal model using the residual maximum-likelihood methodology.
Establishing breeding programs that improve farmed fish performance across multiple environments is crucial in a globalized aquaculture market.
Animal breeding programs have been very successful in improving the mean levels of traits through selection. However, in recent decades, reducing the variability of trait levels between individuals has become a highly desirable objective. Reaching this objective through genetic selection requires that there is genetic variation in the variability of trait levels, a phenomenon known as genetic heterogeneity of environmental (residual) variance.
Selection for increased body weight at harvest in Nile tilapia (Oreochromis niloticus) was carried out for five generations from 1991 to 1996, as a part of the project Genetic Improvement of Farmed Tilapias (GIFT). The base population for selection was composed of a mixture of various three- and four-way cross individuals descending from four wild African strains and four farmed Asian strains.
The main objectives of this study were to evaluate growth performance and estimate line crossing parameters of improved Abbassa tilapia strain and a commerciall Manzala strain within a complete diallel cross at 6 weeks old after hathing. This is done in order to determine the optimum utilization of these strains and crosses for the production of premiun growth and survival of tilapia seeds.
The development of genomic markers is described for Nile tilapia, Oreochromis niloticus, using the Diversity Arrays Technology (DArT) genotype-by-sequencing platform. A total of 13 215 single nucleotide polymorphism (SNP) markers and 12 490 silicoDArT (dominant) markers were identified from broodstock of two selective breeding programs [Genetically Improved Farmed Tilapia (GIFT) strain from Malaysia and the Abbassa strain from Egypt]. Over 10 000 SNPs were polymorphic in either strain, and 2985 and 3087 showed strain-specific polymorphisms for the GIFT and Abbassa strains respectively.
The objectives of this study were (i) to quantify the degree of G x E by assessing the growth performance of Genetically Improved Farmed Tilapia (GIFT) across three countries (Malaysia, India and China) and (ii) to quantify the genetic heterogeneity of environmental variance for body weight at harvest (BW) in GIFT as a measure of micro-environmental sensitivity.