Effects of L-carnitine and Dietary Protein on Body Composition and Liver Lipid Content in Juvenile New GIFT Strain Nile Tilapia (Oreochromis niloticus)

To assess the effects of different levels of dietary protein and L-carnitine on body composition and liver lipid content in juvenile Nile tilapia, triplicate groups of fish were fed on three levels of dietary protein (22, 25 and 28%) and five levels of L-carnitine (0, 200, 400, 600 and 800 mg kg(-1)) for a period of 56 d. The whole body and muscle protein contents increased, but the lipid content decreased with the increases in dietary protein levels. At the same dietary protein levels, protein contents in whole body and muscle tissue increased with the increases in L-carnitine levels. Lipid contents in whole body, muscle tissue and liver in all treatment groups decreased with the increases in L-carnitine levels. This experiment demonstrated that L-carnitine supplementation can help improve utilization of fats from the diets.