Pengembangan pemakaian hasil samping agroindustri berbahan dasar jagung sebagai alternatif bahan baku pakan ikan kerapu tikus Cromileptes altivelis

ABSTRACTThis experiment was conducted to evaluate the use of by product of corn ethanol industry, DDGS (distiller dried grain with soluble) and hominy as feed raw material on digestibility and the growth performance of humpback grouper Cromileptes altivelis juvenile. Three experimental diets containing isoprotein (48%) but different in DDGS contain were used. Diet A containing 0% of DDGS and hominy while diet B and C containing 10.13% (6.13% of DDGS and 4% of hominy) and 19.05% (15.05% of DDGS and 4% of hominy). Reduce of fish meal level in the diet was happen as a consequence of balancing amino acid. For digestibility experiment and Cr2O3 at level of 0.05% was used as a tracer. The feces were daily collected 30‒60 minutes after feeding for 14 days. Dry matter and protein were used as digestibility parameters. Completely randomized design with three treatments and two replicates was used in this experiment. Humpback grouper with an average weight of 11‒14 g were reared at floating net cages (FNG) of 3×2×1.5 m3. The stocking density for each cage was 167 fish/FNG and reared for six months. For digestibility measurement 30 fish were held in cylindrical fiber tank filled with 800 L of sea water. Fish were fed three times daily at satiation level. For maintaining net in a clean condition net was changed in every ten days. Feed consumption, digestibility of protein and total, growth performance indicator i,e specific growth rate, feed efficiency protein and lipid retention were used as evaluating parameters. The results showed that the fish fed with diet containing DDGS (6.13%) dan hominy (4%), at the level of 10.13% (diet B), shows similar growth performance indicators with the fish fed diet A (0% of DDGS and hominy) and the growth performance indicator was higher when being compared to those fish fed diet C (containing 19.05% of DDGS (15.05%) and hominy (4%)) (p<0.05). More over the inclusion of DDGS and hominy at the level of 10,13% give no negatif impact to feed palatability (shown by total feed consumption value) and digestibility of protein. The increasing level of DDGS and hominy more than 10% reduced palatability and protein digestibility. Based on this research, DDGS and hominy can be used up to 10% in the feed formulation of humpback grouperKeywords: digestibility, growth performance, DDGS, hominy, humpback grouper, Cromileptes altivelisABSTRAKPenelitian ini dilakukan untuk mengevaluasi pemanfaatan limbah jagung dari industri etanol dalam bentuk distillate dried grain with soluble (DDGS) dan homini sebagai bahan baku pakan terhadap kinerja pertumbuhan ikan kerapu bebek Cromiliptes altivelis. Ikan yang digunakan dalam penelitian ini adalah juvenil ikan kerapu bebek berukuran 11‒14 g. Ikan dipelihara dalam karamba jaring apung yang berukuran 3×1,5×2 m3 dengan kepadatan 167 ekor/jaring. Ikan diberi pakan sampai kenyang sebanyak dua kali sehari. Untuk menjaga agar jaring tetap bersih maka dilakukan pergantian jaring setiap satu sampai dua minggu sekali. Ikan dipelihara selama lima bulan dan setiap bulan dilakukan sampling. Tiga macam pakan digunakan dalam penelitian ini dengan kadar protein 47% dan rasio energi protein 10 kkal/g protein. Pakan A adalah pakan yang tidak mengandung DDGS dan homini, pakan B mengandung DDGS 6,13% dan 4% (total 10,13%), dan pakan C mengandung DDGS 15,05% dan Homini 4% (total 19,5%). Untuk mengevaluasi ketercernaan nutrien maka kromium oksida (Cr2O3) digunakan sebagai penelusur. Penelitian ketercernaan dilakukan di laboratorium dengan menggunakan fiber dengan volume 800 L. Rancangan acak lengkap dengan tiga perlakuan dan dua ulangan digunakan dalam penelitian ini. Hasil penelitian menunjukkan bahwa nilai ketercernaan nutrien tidak berbeda sampai total kadar DDGS dan homini 10,13% (pakan B) dan peningkatan DDGS serta homini sampai 19,05% (pakan C) menurunkan nilai ketercernaan. Ikan yang diberi pakan dengan DDGS sebesar 10,13% (pakan B) memiliki nilai efisiensi pakan, sintasan, laju pertumbuhan spesifik, konsumsi pakan dan retensi protein yang sama dengan pakan tanpa DDGS (pakan A), akan tetapi nilai-nilai tersebut lebih tinggi jika dibandingkan dengan ikan yang diberi pakan B (p<0,05). Retensi lemak ikan yang diberi pakan B memiliki nilai yang lebih tinggi jika dibandingkan dengan ikan yang diberi pakan A dan C. Dari penelitian ini dapat disimpulkan bahwa DDGS dan homini dapat digunakan sebagai bahan baku pakan ikan kerapu bebek sampai level 10,13% (DDGS 6,13% dan homini 4%).Kata kunci: pertumbuhan, ketercernaan, DDGS, homini, ikan kerapu bebek, Cromileptes altivelis