Digestibility study of various of seaweed in nile tilapia Oreochromis niloticus and giant gouramy Osphronemus gouramy

R. Samsudin^a*, MTD. Sunarno^a, D. Jusadi^b, LH. Suryaningrum^a
^a Institute of Freshwater Aquaculture Research and Development (IFARaD), Jl. Sempur No 1 Bogor, Indonesia 16154
^b Faculty of Fisheries and Marine Science, Bogor Agricultural Institute, Jl. Rasamala, Bogor, Indonesia 16680

The experiment was conducted to determine the apparent digestibility of various of seaweed in nile tilapia Oreochromis niloticus and giant gouramy Osphronemus gouramy. Apparent digestibility coefficients (ADCs) of ingredients were determined using indirect techniques using chromium oxide as the marker and collecting faecal material by passive settlement. Ingredients tested included wild (Sargassum sp (WS); Caulerpa sp (WC) and Rhodimenia sp (WR)) and cultured (Eucheuma cottoni (CE), Sargassum (CS)) sea weed. Wild type seaweed were collected from Binuangen Beach, Pandeglang District, Province of Banten. Cultured seaweed collected from Brebes District, Province of Central Java. The majority of these ingredients were examined at the 30% inclusion level and reference diet at the 70% level. Nile tilapia with initial weight 10.25±0.53 g.fish^-1 and giant gouramy with initial weight 18.32±1.33 g.fish^-1 were used as experimental fish. 30 aquaria (volume = 60 l) were equipped with thermostat and aeration was used in this experiment. Stocking density for each fish were 30 and 20 fish.aquarium^-1 respectively. In all experiments, faecal material was collected from n = 3 replicate tanks. The result showed that there were various values of ADC among seaweed in tilapia. The ADC value for WS, WC, WR, CE, and CS in nile tilapia were 59.32; 64.29; 58.50; 64.82; and 61.18% respectively. The best protein digestibility value was found for WC (66.42%). CE gave the best crude fiber digestibility with the value 65.77%. The ADC value for WS, WC, WR, CE, and CS in giant gouramy were 62.33; 66.72; 59.81; 68.07; and 63.21% respectively. The data generated in this study will be useful for formulating research and commercial feeds seaweed based.