عنوان مقاله [English]
Study of dietary lipid levels is too important; therefore, in order to evaluate the effects of different lipid levels on growth indices and survival rates of gold fish, a nutritional study was designed for 180 days on fish with an average of 3.5 grams to achieve the rate of desired fat requirements. Three different levels of lipid level 9, 12 and 15 % with digestible energy of 3790 to 3900 Kj / kg were considered in this study. The results of the effect of different dietary lipid levels indicated a significant increase in final body weight, body weight gain, body weight gain, specific growth rate, condition factor and survival rate, and a significant decrease in food conversion rate (P<0.05). Based on the findings of this study, the increase in fat content by 15% has led to improved studied indices. The highest growth, survival rate and the best feed conversion ratio were obtained at 15% lipid. Accordingly, in this study the optimum lipid content for diet of goldfish was considered as 15%.