Selection response and heritability in growth trait of first generation (G1) of djambal catfish population (Pangasius djambal)

Djambal catfish (Pangasius djambal) is a freshwater fish species native to Indonesia. It can be found especially in Sumatera and Kalimantan rivers. An effort to increase productivity of djambal catfish in aquaculture can be done through the use of superior broodstock that can be obtained from a breeding program. This study implemented a breeding program to obtain the population of first generation (G1) with faster growth compared to previous generation. The selection method was within family selection. Breeding candidates were created by half-sib mating of broodstocks with male to female ratio of 2:1 Ten families resulting from the spawning were reared in indoor area until they reached juvenile size. The juvenile were then grown in net cage sizing of 3 x 5 x 1.5 m suspended in an earthen pond at the density of 10 fish m-2 for five months. Fish selection was done on the basis of body weight. The observed parameters were growth rate, coefficient of variance, differential selection, selection response, and heritability. This study showed that G1 population of djambal catfish has faster growth rate than the G0 population. The average absolute weight of G1 population was 701.85±118.92 g; control population was 564.70±74.52 g; and selected population was 889.56±61.97 g. The value of coefficient of variation, selection response, differential selection, and heritability were 16.94%, 137.15 g (24.29%), 187.71 g (26.74%) and 0.33, respectively. The implementation of within family selection method in catfish has proved effective to obtain next generation with faster growth than previous generation.