Growth, production and feed conversion performance of the gurami sago (Osphronemus goramy Lacepède, 1801) strain in different aquaculture systems

Background: Giant gourami ( Osphronemus goramy, Osphronemidae), belonging to gurami sago strain, is an important economic fish species that was newly released for domestication in 2018 in Indonesia. The present study aimed to determine the growth, production and feed conversion efficiency of gurami sago strain in different aquaculture systems. Methods: A mean of 240 juveniles were stocked (initial weight mean, 54.53 g and length 13.88 cm) into concrete ponds, floating net cages and earthen freshwater ponds (12 m (3)) with three replicates of each. The juveniles were fed a floating commercial pellet diet containing 30% crude protein and 5% crude lipids. Feed was supplied at 3% of fish biomass per day throughout the 90 days of the experiment. The research was conducted in the area surrounding Lake Maninjau of Indonesia. Results: After 90 days, the mean weight of fish reared in concrete ponds was 166.86 g, floating net cages was 179.51 g and earthen freshwater ponds was 149.89 g. The mean final biomass was 37.64 kg for concrete ponds, 41.27 kg for floating net cages, and 33.72 kg for earthen freshwater ponds. The specific growth rates (%/day) for concrete ponds, floating net cages and earthen freshwater ponds were 0.67, 0.75 and 0.62, respectively. The feed conversion rates were 1.45 for concrete ponds, 1.30 for floating net cages and 1.87 for earthen freshwater ponds. The net yields (kg m (ˉ3)) were 2.05 for concrete ponds, 2.27 for floating net cages, and 1.73 for earthen freshwater ponds. The exponents (b) of the length–weight relationship were calculated for concrete ponds (1.0146), floating net cages (1.2641), and earthen freshwater ponds (1.0056). Conclusion: The study showed that the growth performance, production and feed conversion efficiency of the gurami sago strain were the best found in floating net cages and considered a new aquaculture system in the future.