Abstract:

Resilience is the ability of an animal to adapt with environmental changes while maintaining consistent performance over time. A selective breeding program for growth in brackish water of Sukamandi strain tilapia is conducted in Indonesia. The resilience of fish is also important for producing tilapia in variable saline conditions. The objectives of this study were to estimate the genetic parameters of resilience for Sukamandi strain, expressed as consistency in growth. We used the log-transformed variance of deviations (LnVar) from weight, recorded five times during grow-out. We also estimate the correlation of LnVar with weight (W), daily growth coefficient (DGC), condition factor (K) and survival (S). The heritability of LnVar in time point 4 and 5 were 0.02 and 0.07, respectively. The genetic correlations were positive (0.35-0.76) for LnVar with W, DGC, S and negative (-0.31) with K. These estimates showed that selection for growth and survival will moderately increase LnVar and may lead to the decreasing resilience. However, selection for K could contribute to increased resiliency of tilapia.