摘要：This study was aimed to determine optimum dose of L-Ascorbyl-2-Phosphate Magnesium in the diet of patin, Pangasius hypophthalmus fingerlings. Five isoprotein and isocaloric diets containing different dose of L-Ascorbyl-2-Phosphate Magnesium, i.e. 0, 25, 75 and 100 mg/kg diet were used in this experiment. Fish with an average size of 5.00±0.11 g were maintained at a density of 15 fish per aquarium. Fish were fed three times a day at satiation , for 40 days. The results of study shows that vitamin C content in fish body increased as the vitamin C level of the diet increased. Similar pattern to vitamin C content was also found in protein retention, lipid retention, daily growth rate, and feed efficiency ( p Keywords: vitamin C, patin, Pangasius hypophthalmus . ABSTRAK Penelitian ini bertujuan untuk menentukan kadar optimum L-Ascorbyl-2-Phosphate Magnesium dalam pakan ikan patin, Pangasius hypophthalmus ukuran sejari. Lima macam pakan isoprotein dan isokalori mempunyai kandungan L-Ascorbyl-2-Phosphate Magnesium berbeda, berturut-turut 0, 25, 50, 75 dan 100 mg/kg pakan telah digunakan dalam penelitian ini. Benih berukuran rata-rata 5,00±0,11 g dipelihara dalam akuarium dengan kepadatan 15 ekor per akuarium. Ikan diberi pakan tiga kali sehari, secara at satiation , selama 40 hari. Hasil penelitian menunjukkan bahwa kadar vitamin C tubuh meningkat sejalan dengan kadar vitamin C pakan. Demikian pula retensi protein, retensi lemak laju pertumbuhan harian, efisiensi pakan mengikuti pola yang sama seperti kandungan vitamin C tubuh (p Kata kunci: vitamin C, ikan patin, Pangasius hypophthalmus .
