Genetic parameter estimates for resistance to Enteric Septicemia of Catfish on Pangasianodon hypophthalmus

Abstract

Genetic parameters were estimated for resistant traits against Enteric Septicemia of Catfish (ESC) on the first generation of selection on striped catfish. In total, 8,207 and 5,838 individuals from 147 and 130 full-sib families were challenged by Edwardsiella ictaluri causing ESC on fingerlings and tested growth in pond accordingly. Harvest body weight (HW), length (HL) and survival (SURGROW) from grow-out test and ESC resistant traits such as binary alive-dead survival (SUR) and time to dead (TIME) at different truncated points from challenged test of fingerlings were recorded. Heritability for each trait and genetic correlations among these recorded traits were estimated. High heritabilities were found for HW (0.48) and HL (0.47), and mostly from medium to high values were estimated for SURGROW (0.23), SUR (0.13 - 0.40) and TIME (0.25 - 0.39). Genetic correlations among different truncated SUR and TIME traits were almost highly positive (0.57 - 0.99). Genetic correlations among different truncated SUR and TIME traits with HW and SURGROW were low positive (0.10 - 0.40). In summary, selection for ESC resistance would not negatively affect the growth in fingerling stage.