Of all the species in the Mekong Delta, striped catfish (Pangasianodon hypophthalmus) is the most economically important fresh water fish farmed in Vietnam. However, the challenges to its culture have been associated with many reasons but above all, lack of high quality seed, water pollution, diseases epidemic and lack of elite brooders with high genetic variability which subsequently have led to prolonged production cycles and hence high costs of production. The direct selection responses from the previous three generations for BW traits was 9.3% genetic gain per generation and this justifies the success of the selection. This study aims at estimating heritability and the selection responses for growth traits in the 4th selected generation of striped catfish of a breeding program using a nested mating design (30 sires and 60 dams) where 7200 individual fingerlings will be independently raised in hapas from 120 families and afterwards tagged using Passive Integrated Transponder (PIT) tags after 120 days. They will be communally tested in an outdoor rectangular pond (2,000m²) till harvest at an average body weight of 1.0 kg (6 months of culture). Univariate and bivariate linear animal mixed models will be used to estimate variance and covariance components of four groups of traits (body, carcass, fish body condition and survival) during grow-out period. Findings of this study will generate information that will be used in broodstock selection with desired additive genetic traits for sustainable increased commercial production of striped catfish in the Mekong Delta.
Keywords: Pangasianodon hypophthalmus, heritability, genetic variability, selection.