Phenotypic diversity in three generations of domesticated Asian redtail catfish, Hemibagrus nemurus (Valenciennes, 1840) in Indonesia

It is necessary to characterize the phenotypes of each produced generation to evaluate the rate of changes to support the success of a domestication program. This study aimed to analyze the phenotype diversity of three domesticated Asian redtail catfish (Hemibagrus nemurus) generations (G-1, G-2 and G-3) based on parameters such as truss morphometry, growth performance, and survival rate. The truss morphometric analysis was performed using 30 individuals sampled from each generation. Growth performance and survival rate analysis were experimentally carried out using a completely randomized design (CDR) with three replications. Rearing of the three Asian redtail catfish generations begun with an acclimatization period for one week and continued through up to 90 days. Rearing was done in 9 concrete ponds (3 x 2 x 1 m) with a circulation system. The water level in each pond was maintained at 80 cm. The stocking density was 100 individuals m. Fish were fed on commercial pellet containing protein (28%) at a 5% feeding rate (of the total biomass of fish). The results of truss morphometric analysis canonical function on 21 characteristics showed differences in characters occurring in the midsection (B3) and rear body of the fish (C1, C3, and C5). The analysis of intrapopulation similarity index revealed the highest values in G-1 and G-2 (60.0 %), whereas the lowest was observed in G-3 (40.0%). The results of domesticating three generations of Asian redtail catfish for 90 days showed the G-3 had the highest length growth performance, SGR, FCR and survival rate (p < 0.05) which were 6.49±0.39 cm; 0.70±0.03% per day; 2.3 and 67.67%, respectively.