Response to Mass Selection for Disease Resistance in Walking Catfish,Clarias macrocephalus

Two populations of walking catfish, Clarias macrocephalus, with different genetic backgrounds were subjected to mass selection for resistance to Aeromonas hydrophila for one generation by IP injection of 1 x 10¹ cells A. hydrophila/mL. No significant difference between selected and control lines were observed in survival rate and time at which 50% mortality occurred after disease challenge. Differences in mean were estimated. Heritability values for the two populations were 0.17 and 0.10.