A breeding program for Nile tilapia in Brazil: Results from nine generations of selection to increase the growth rate in cages. (22nd September 2021) - Yoshida, Grazyella Massako
Abstract: Variance components and heritabilities for daily weight gain (DWG) were estimated for Nile tilapia farmed in cages across nine generations (G1–G9) of selection in a breeding program in Brazil. DWG was measured in 16, 272 accumulated tagged animals representing 535 full‐ and half‐sib families of Nile tilapia under cage farming. The additive genetic variance showed a slight variation (0.051–0.066), and heritability estimates ranged from 0.20 to 0.33. The common environmental effect accounted for a higher proportion of the total variance in DWG, especially in the last generations (6%–24%). A genetic trend based on all data available showed a substantial increase in the DWG (about 3.3% per generation) of Nile tilapia across nine generations of selection. Furthermore, our results demonstrate ample scope for further genetic improvement.