Dietary choline requirement of fingerling yellowtail

摘要

Two experiments were conducted to identify choline deficiency signs in fingerling yellowtail, Seriola quinqueradiata and to determine their dietary requirement for this vitamin. Fingerlings were fed purified diets with and without supplemental choline chloride (control and choline-deficient diets, respectively) for a period of 20 days. Fish fed the choline-deficient diet developed deficiency signs such as anorexia and poor growth within 5 days. On day 8, the diet for half of the choline-deficient fish was changed to the control diet, which contained 800 mg choline chloride/100 g of diet. Deficiency signs in these fish disappeared whithin 3 days. In the requirement experiment, diets with nine levels of choline chloride (0, 10, 25, 50, 100, 200, 300,400 and 800 mg/100 g of diet) were fed to fingerlings for a period of 17 days. Weight gain and liver choline data indicated that the choline requirement of fingerling yellowtail are 210-290 mg (as chloride)/100g of diet.