THE EFFECT OF DIETARY L-CARNITINE ON GROWTH-PERFORMANCE AND LIPID-COMPOSITION IN RED-SEA BREAM FINGERLINGS

The present study is concerned with the effect of dietary L-carnitine supplementation on growth and lipid composition of red sea bream finge rlings. Varying dietary levels of L-carnitine (75, 545, 1087, 2088, an d 4162 mg/kg) were administered to five groups of fish during a 42 day period. Fish receiving 2088 mg/kg L-carnitine in their diet showed th e highest increase in growth. Feed efficiency was positively correlate d with the growth rate of fish and remarkably improved as the amount o f L-carnitine in the diet increased up to 2088 mg/kg. Analysis of lipi d composition showed that L-carnitine reduces the amount of free fatty acids in liver indicating an increased fatty acid utilization. Specif ically it seems that L-carnitine promotes the utilization of long chai n fatty acids (20-22 carbon atoms) judging from their reduced content in livers of fish fed on L-carnitine supplemented diets.