PROFIL PERTUMBUHAN, ENZIMATIS, DAN NUTRISI IKAN BANDENG (Chanos chanos) GENERASI KEDUA (G-2) TERSELEKSI DENGAN MENERAPKAN STANDAR OPERASIONAL PROSEDUR (SOP) PEMELIHARAAN LARVA
Isu nasional menurunnya produksi budidaya ikan bandeng di tambak pantai utara Pulau Jawa didugasebagai akibat rendahnya kualitas benih produk Hatchery Skala Rumah Tangga (HSRT) di Bali, yang secara kontinu merupakan sumber utama pasok benih. Banyak faktor yang mempengaruhi kualitas benih, antara lain kualitas telur dan induk, serta manajemen pemeliharaan induk dan larva. Tujuan penelitian ini adalah untuk mengevaluasi performa pertumbuhan,aktivitas enzim pencernaan dan nutrisi benih ikan bandeng dari HSRT dan generasi kedua (G2) terseleksi yang dipelihara berdasarkan standar operasional prosedur. Penelitian dilakukan di tambak Pejarakan, dengan hewan uji benih produk HSRT dan benih generasi ke-2 (G-2) terseleksi dengan panjang total rata-rata 11,79 ± 1,64 mm, masing-masing dengan padat tebar 5.000 ekor/petak dengan luasan 0,5 Ha/petak, diberi pakan jenis pelet kering berkadar protein 25 % dan dipelihara selama 6 bulan. Hasil penelitian menunjukkan performa benih ikan bandeng dipengaruhi oleh sumber induk dan manajemen pemeliharaan saat larva. Pertumbuhan benih ikan bandeng asal HSRT dengan SOP pemeliharaan larva menunjukkan peningkatan laju pertumbuhan panjang dan bobot sebesar 10,11% dan 47,18% lebih tinggi dibandingkan benih G2-terseleksi, dan 13,82% dan 50,55% lebih tinggi dibandingkan benih HSRT tanpa SOP. Aktivitas enzimatis pada benih HSRT dengan SOP lebih efisien dibandingkan benih G2-terseleksi. Aktivitas enzimatis pada benih HSRT tanpa SOP adalah yang paling rendah dimana hal ini terlihat dari laju pertumbuhannya yang juga paling rendah. Benih HSRT yang dipelihara dengan SOP mampu menekan rasio konversi pakan sebesar 28,29% lebih rendah dibandingkan benih G2-terseleksi, dan 22,64% dibandingkan benih HSRT yang dipelihara tanpa SOP. Currently, there is a national concern regarding the decreasing of milkfish production from ponds in North Java allegedly due to a low quality of milkfish seed produced by small-scale hatcheries in Bali, which is the main producer of milkfish seed. Some factors can influence seed quality, such as quality of egg and broodstock also rearing management of broodstock and larvae. The aim of this experiment was to evaluate morphological aspect (growth rate) and biological aspect (digestive enzymes activities) of seed from backyard hatchery and selected G2 milkfish. Research on grow-out of milkfish seed was conducted at the IMRAD ponds facility in Pejarakan, using milkfish seed produced by small-scale hatcheries as well as selected second-generation (G-2) seed, each with the density of 5,000 seed/pond (1 pond=0.5 ha). The seeds were fed with dry pellet and reared for 6 months.The result showed performance of seed in terms of morphological and biological influenced by broodstock itself and larvae rearing management.The growth of seed of HSRT origin with larvae rearing SOP had increased the length of and weight growth rates of 10.11% and 47.18%, respectively compared to seed G2 selected and 13.82% and 50.55% from seed HSRT without SOP. Enzymatic activity in HSRT seed with SOP was more efficient than that of selected G2 seed. Enzymatic activity in HSRT seed without SOP was the lowest in which correlated to the lowest growth. Seed from HSRT origin with SOP had better feed conversion ratio which was 28.29% lower than that of selected G2 seed and 22.64% lower than that of HSRT seed without SOP.