Two distinct nutritional experiments were conducted sequentially with fry of channel cattish Ictalurus punctatus Initial weight of fish was 0.030 ± 0.003 g in experiment I and 1.36 ± 0.03 g in experiment 2 In both experiments, fry were fed a semipurified, casein-gelatin-based diet containing no ascorbate supplement (AA-frce) or a diet supplemented with 640 mg ascorbale/ kg as ascorbyl monophosphate (AP); fry used in experiment 2 had been given the AP-supplemented diet in experiment I Fish fed a diet devoid of vitamin C showed significantly reduced growth after 14 d in experiment 1 and 28 d in experiment 2 In experiment 1, fry fed starter feed lacking vitamin C showed significantly increased mortalities during the sixth through eighth weeks At the same lime, gross clinical signs of deficiency appeared, such as darker skin pigment, scoliosis lordosis and eroded fins In experiment 2, larger fry did not show any mortality or external pathologies during the 54 d of the feeding study The ascorbate concentration in whole fish bodies before exogeneous feeding was 19.6 ± 0.7 μ, g/g and did not change after 8 weeks when fish increased their body weight 48-fold on an AP-supplemenled diet (experiment 1) Small fry fed an AA-free diet increased their body weight 9-fold, and ascorbate was below detectable levels (0.5 pμg/g) Larger fry fed an ascorbate-supplemented diet had significantly higher concentrations of ascorhate in the liver (8.3 ± 0.3 μ, g/g) and kidneys (13.2 ± 0.9 μ, g/g) than fish fed a diet devoid of this vitamin.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Aquatic Animal Health|
|State||Published - Mar 1996|
ASJC Scopus subject areas
- Aquatic Science