Determination of growth performance of goldfish (Carassius auratus L.1758) fry fed with diets supplemented different levels of L-carnitine

In this study, the effect of L-karnitin on growth in diets for goldfish fry, Carrasius auratus was investigated. Five isonitrogenous, isolipidic and isoenergetic diets were formulated to contain 40% protein, 6% lipid and 3540 DE kcal kg-1. L-karnitin was supplemented by 0 (control group), 250, 500, 750 ve 100 mg kg-1. Goldfish fry were reared in 65 lt glass aquaria maintained in stagnant water. Each dietary treatment was tested in triplicate groups of 20 fish per aquarium in a completely randomized design. Fish with average weight of 0,311±0,01 g were fed the diets twice per daily to apparent satiation for 84 days. In the experiment, diets were evaluated based on growth performance and diet utilization. End of the research, there was no significant difference in growth performance, condition factor, specific growth rate, feed conversion ratio and protein efficiency ratio between dietary treatments. Survival was similar for all dietary treatments (100%). In conclusion, supplemental dietary L-carnitine has no beneficial effects on improving growth performance and feed conversion ratio in goldfish fry.