イシダイ飼料の至適アスコルビン酸添加量

概要

論文の詳細を見る
Juvenile Japanese parrot fish Oplegnathus fasciatus were fed purified test diets supplemented with 0, 25, 50, 75, 100 and 300mg of ascorbic acid (AsA) per 100g of diet. In the no AsA supplemented diet group, growth declined and deficiency signs of deformity or abnormal swimming appeared from week 8. At week 16, the values of blood character-istics such as hemoglobin, hematocrit, glucose, total protein, alkaline phosphatase and calcium, and the hepatosomatic index of the fish fed diet containing no AsA supplement had significantly decreased than the other groups. On the other hand, normal growth and regular values of hematological parameters with no deformities were observed among the fish groups fed with diets with supplementary AsA levels of 25mg per 100g diet or greater. Moreover, the AsA contents of the brain, gill, kidney and liver of the fish were reached saturation level when the supplementary AsA level exceeded 50mg per 100g of diet. These results indicate that the sufficient supplementary AsA level to maintain normal growth and health of the Japanese parrot fish was estimated to be 25mg of AsA per 100g of diet under this experimental condition. It was also estimated that 50mg of supplementary AsA per 100g of diet is needed to saturate the tissue AsA levels.