Feeding strategy does affect carbohydrate utilization by hybrid Tilapia Oreochromis niloticus x O. aureus

An eight-week growth trial was conducted to evaluate the effect of feeding strategy (continuous fed vs two meals per day) on the utilization of carboh ydrate by juvenile hybrid tilapia, Oreochromis niloticus x O. aureus. The c arbohydrates were starch and glucose, and included at 44% of the diet. Aver age initial body weight of the fish was 0.47+/-0.01 g, and fish were fed at a rate of 5% body weight per day. The results indicated that weight gain w as significantly higher (p<0.05) for fish fed continuously than for those f ed two meals a day for both carbohydrate diets. Higher hepatic phosphofruct okinase (PFK) and malic enzyme (ME) activities were observed in the continu ous-fed fish than in meal-fed fish. Hepatic asparate transaminase (AST) and alanine transaminase (ALT) activities of the continuous-fed fish with gluc ose diet were lower than those of the meal-fed fish. Plasma AST and ALT act ivities were higher in the meal-fed fish than in the continuous-fed fish. T hese data suggest that carbohydrate utilization by tilapia is affected by f eeding strategy and that continuous fed improves carbohydrate utilization.