Dietary vitamin C requirement of fingerling, Cirrhinus mrigala (Hamilton), based on growth, feed conversion, protein retention, hematological indices, and liver vitamin C concentration.

摘要

This study was conducted to quantify dietary vitamin C requirement of fingerling, Cirrhinus mrigala, (0.79+or-0.07 g; 3.51+or-0.15 cm) by feeding casein-gelatin based purified diets (400 g/kg crude protein; 3.45 kcal/g digestible energy) containing nine levels of vitamin C as l-ascorbyl-2-polyphosphate (0.0, 5, 15, 25, 35, 45, 55, 75, and 95 mg vitamin C equivalent/kg diet) to triplicate groups of fish to apparent satiation for 16 wk. Absolute weight gain (AWG, g/fish), feed conversion ratio (FCR), protein retention efficiency (PRE%), RNA/DNA ratio, hemoglobin (Hb, g/dL), and hematocrit value (Hct%) were taken as the response criteria to determine vitamin C requirement of mrigal. Fish fed diet with 35 mg/kg vitamin C had significantly higher AWG (9.94 g/fish), FCR (1.39), PRE (27.72%), RNA/DNA ratio (4.18), Hb (11.15 g/dL), and Hct (34.44%) values. However, liver vitamin C concentration was found to be higher (64.92 micro g/g wet tissue) in diet containing 45 mg vitamin C/kg. Broken-line regression analysis of AWG data estimated the requirement of 35.65 mg/kg, whereas that of the liver vitamin C concentration data projected the requirement to 41.99 mg/kg.