The growth rate of Nile tilapia Oreochromis niloticus fry fed on fermented Lemna sp. meal

ABSTRACT This research aimed to evaluate the supplementation of fermented Lemna sp. meal (FLM) in the artificial diet on the growth rate of Nile tilapia Oreochromis niloticus. The research design used was complete randomized design consisting of four treatments; A (0% FLM), B (20% FLM), C (30% FLM), and D (40% FLM) in triplicates. The parameters observed were the nutritional composition of LFM, daily growth rate (DGR), feed conversion ratio (FCR), survival rate (SR), and water quality. Fermentation with Effective Microorganism 4 (EM4) has increased crude protein and crude lipid of FLM respectively 5.60% and 5.76%. However it decreased the crude fiber of FLM up to 15.27%. The result suggested that supplementation of FLM 0–40% in the artificial diet could give DGR 0.81–1.20%, FCR 2.48–2.97; and SR 72%–84% in Nile tilapia. The addition of 40% LFM showed the best result among all treatments. Key words: Lemna meal, EM4, fermentation, Nile tilapia fry ABSTRAK Tujuan dari penelitian ini adalah untuk mengevaluasi penggunaan tepung Lemna sp. fermentasi (TLF) pada pakan buatan terhadap laju pertumbuhan ikan nila Oreochromis niloticus. Rancangan penelitian yang digunakan adalah rancangan acak lengkap (RAL) terdiri atas empat perlakuan, yaitu A (0% TLF), B (20% TLF), C (30% TLF), dan D (40% TLF) dengan masing-masing tiga ulangan. Parameter yang diamati dalam penelitian antara lain nilai nutrisi TLF, laju pertumbuhan harian (LPH) ikan nila, rasio konversi pakan (RKP), sintasan (SR), dan kualitas air. Fermentasi dengan Effective Microorganism 4 (EM4) meningkatkan protein kasar dan lemak kasar TLF sebesar masing-masing 5,60% dan 6,76%, akan tetapi menurunkan serat kasar hingga 15,27%. Hasil penelitian menunjukkan bahwa pemberian TLF 0–40% dalam pakan komersial menghasilkan LPH 0,81–1,20%; RKP 2,48– 2,97; dan SR 72%–84%. Pemberian TLF sebanyak 40% merupakan perlakuan yang menunjukkan hasil terbaik. Kata kunci: tepung Lemna, EM4, fermentasi, benih ikan nila