<![CDATA[ABSTRACT The study was aimed to determine the optimum dietary protein level and energy protein ratio which can optimize growth performance of the eel A. bicolor bicolor on nursery phase. Four treatments and three replications were applied in this study. The treatments were P1, containing 37.66% protein with energy protein ratio 14.75 kcal GE/g (37.66%; 14.75 kcal GE/g), treatment P2 (41.30%; 13.51 kcal GE/g), treatment P3 (45.38%; 12.27 kcal GE/g), and treatment P4 (49.60%; 11.31 kcal GE/g). Eels used for this study were 6.5±0.3 g in average body weight. Eels were reared in a series of aquaria with dimension 90×40×40 cm3 and filled with 100 L of fresh water. Total weight of eel stocked in aquarium were 400 g. Eels were fed until satiated twice a day at 8 am and 4 pm for 60 days. The result showed that different protein level and energy protein ratio was significantly affected growth performance (feed consumption, specific growth rate, feed efficiency, protein retention, and lipid retention), protein and fat of whole body eels at confident limit of 5%. In contrary, there was no significant different on the survival rate, hepatosomatic index, ash content, and nitrogen free extract of the body eel. The optimal growth performance was reached by dietary protein level and energy protein ratio of 45.38%; 12.27 kcal GE/g and 49.60%; 11.31 kcal GE/g. Keywords: Anguilla bicolor bicolor, energy protein ratio, feed, growth performance, protein ABSTRAK Penelitian ini bertujuan menentukan kadar protein dan rasio energi protein optimum yang dapat meningkatkan kinerja pertumbuhan ikan sidat A. bicolor bicolor fase pendederan. Empat macam perlakuan dan tiga ulangan digunakan dalam penelitian ini. Perlakuan tersebut adalah P1 yang mengandung protein 37,66%; dengan rasio energi protein 14,75 kkal GE/g (37,66%; 14,75 kkal GE/g), perlakuan P2 (41,30%; 13,51 kkal GE/g), perlakuan P3 (45,38%; 12,27 kkal GE/g) dan perlakuan P4 (49,60%; 11,31 kkal GE/g). Bobot rata-rata ikan sidat yang digunakan adalah 6,5±0,3 g. Ikan sidat dipelihara dalam akuarium berukuran 90×40×40 cm3 dengan volume air 100 L. Total bobot ikan yang digunakan dalam setiap akuarium adalah 400 g. Ikan sidat diberi pakan sekenyangnya dengan frekuensi dua kali sehari yaitu pukul 08.00 dan pukul 16.00 WIB selama 60 hari. Hasil menunjukkan bahwa pemberian kadar protein dan rasio energi protein pakan berbeda, memberikan pengaruh nyata (P<0,05) terhadap kinerja pertumbuhan (jumlah konsumsi pakan, laju pertumbuhan spesifik, efisiensi pakan, retensi protein, retensi lemak), protein tubuh dan lemak tubuh, tetapi tidak berpengaruh nyata (P>0,05) terhadap tingkat kelangsungan hidup, indeks hepatosomatik, kadar abu, dan bahan ekstrak tanpa nitrogen (BETN) tubuh ikan sidat. Kinerja pertumbuhan optimal dicapai oleh kadar protein dan rasio energi protein pakan 45,38%; 12,27 kkal GE/g dan 49,60%; 11,31 kkal GE/g. Kata kunci: Anguilla bicolor bicolor, kinerja pertumbuhan, pakan, protein, rasio energi protein ]]>
