High L-carnitine levels can influence the nutritional efficiency of L-lysine in great sturgeon (Huso huso L.) fingerlings

Abstract

A dose-response method-based study was conducted to investigate the effects of L-lysine supplementation of L-carnitine-enriched diet on growth and biochemical composition of carcass in great sturgeon (Huso huso L.) fingerlings. To do so, the fish was assigned to five groups receiving 0, 0.75, 1.5, 2.25 or 3% L-lysine-enriched diet at 6000 mg/kg L-carnitine level. Feeding was done three times daily on a 4% body weight basis and growth indices and biochemical composition of the carcass were assayed during the 56 days experimental period. Our results indicated that the growth indices of animals fed with L-lysine-supplemented diet and those fed with the basal diet did not differed significantly (p≥0.05) at the end of the experiment. Also, ambiguous pattern of changes was observed in carcass composition of fish fed with L-lysine-supplemented food in comparison with basal diet. It is concluded that the excess levels of L-carnitine may induce lysine/arginine antagonism in the body and suppress growth in fish. © 2013 Taylor & Francis.