GROWTH OF NILE TILAPIA (Oreochormis niloticus) FRY FED WITH COCONUT TESTA-CASSAVA BAGASSE MIXED SUBSTRATE FERMENTED USING Rhizopus oryzae - Pradana, Yudha Wali; Sriherwanto, Catur; Yunita, Etyn; Sujaâi, Imam (Badan Pengkajian dan Penerapan Teknologi (BPPT), 2017)
Utilization of agroindustrial byproduct as cheap raw materials for aquafeed was hampered by its poor nutritional value as well as high antinutrition content which could be overcome through fermentation. Coconut testa (CT) and cassava bagasse (CB) were mixed, and fermented using Rhizopus oryzae for preparing aquafeed. Subsequent feeding test was carried out on tilapias (Oreochormis niloticus L.) using 5 feeding treatments: one unfermented feed (commercial feed 100%), and the other four feeds produced by fermentation using substrate mixture of CT and CB in 4 different ratios, namely 100%:0%, 75%:25%, 50%:50%, and 25%:75%. Feeding 100% commercial feed (true protein 22.64% and crude fibre 14.67%) showed the best results on the fish growth with body weight gain of 3.96 g and feed conversion ratio of 8.63. Meanwhile, feeding fermented feeds (true protein 7.96-20.27% and crude fiber 14.14-18.47%) resulted in body weight gain in the range of 2.22 to 2.75 g with feed conversion ratio of 10.89 to 13.62. Thus, the fermented feeds promoted growth in tested tilapias albeit less optimally than commercial feed did.Keywords: Rhizopus oryzae, Oreochromis niloticus, coconut testa, cassava bagasse, fermentation ABSTRAKPenggunaan hasil samping agroindustri sebagai bahan pakan murah ikan terkendala rendahnya nutrisi dan tingginya antinutrisi yang dapat diatasi melalui fermentasi. Dalam penelitian ini, kulit daging buah kelapa (KK) dan onggok singkong (OS) dicampur dengan perbandingan tertentu, lalu difermentasi menggunakan Rhizopus oryzae untuk pakan ikan. Uji pemberian pakan dilakukan terhadap ikan nila (Oreochormis niloticus L.) dengan 5 perlakuan: satu perlakuan pakan tanpa fermentasi (pakan komersial 100%), dan empat perlakuan pakan fermentasi substrat campuran KK dan OS dengan 4 perbandingan yang berbeda, yakni 100%:0%, 75%:25%, 50%:50%, dan 25%:75%. Pemberian pakan komersial 100% (protein sejati 22,64% dan serat kasar 14,67%) memperlihatkan hasil terbaik pada pertumbuhan ikan nila dengan pertambahan bobot badan 3,96 g dan rasio konversi pakan 8,63. Sebaliknya, pemberian pakan fermentasi (protein sejati berkisar 7,96-20,27% dan serat kasar 14,14-18,47%) menghasilkan pertambahan bobot badan ikan pada kisaran 2,22-2,75 g dengan rasio konversi pakan 10,89-13,62. Dengan demikian pakan fermentasi tersebut mendorong pertumbuhan ikan nila namun kurang optimal dibandingkan pakan komersial.Kata Kunci: Rhizopus oryzae, Oreochromis niloticus, kulit daging buah kelapa, onggok, fermentasi