en aquaculture aquaculture پژوهشي Orginal research papers <p style="margin: 0cm 0cm 10pt; text-align: justify; line-height: 200%; unicode-bidi: embed; direction: ltr;"><font color="#000000"><span new="" style="line-height: 120%; font-family:;" times="">This study was performed to investigate the effects of feeding rates on growth performance, feed conversion and body composition of juvenile snow trout (<i>Schizothorax zarudnyi</i>). For this purpose, fish with an initial body weight of 2.17&plusmn;0.1 g were fed a commercial diet (40% protein, 3.8 Kcal g^-1 diet) at five ration sizes of 2%, 4%, 6%, 8% and 10% of their body weight per day, for 60 days. The feeding trial was conducted in triplicate. Maximum weight gain, best feed conversion ratio (FCR), best specific growth rate (SGR %), highest energy retention (ERE %) and protein efficiency ratio (PER %) were evident for rations of 4&ndash;6% body weight. Second-degree polynomial regression analysis for PER, FCR and ERE indicated the break-points occurred at 4.9, 5.1 and 5.2% BW day^&minus;1, respectively. Maximum body protein content was obtained for 4% and 6% rations. Body moisture, fat and ash content remained unchanged. Based on the above results,</span><span adv="" focio="" style="line-height: 120%; font-family:;"> </span><span new="" style="line-height: 120%; font-family:;" times="">it may be concluded that the 4.9-5.2% body weight per day ration is optimal for the growth, conversion efficiencies and body composition of juvenile <i>S. zarudnyi</i> and it entails favorable economic benefits.</span></font></p> Growth, Body composition, Ration, Schizothorax zarudnyi 507 516 http://jifro.ir/browse.php?a_code=A-10-2093-1&slc_lang=en&sid=1 H. khandan Barani hashem.barani94@gmail.com 100319475328460030307 100319475328460030307 Yes Hamoun International Wetland Research Institute, University of Zabol, Zabol, Iran H. Dahmardeh Dahmardeh 100319475328460030308 100319475328460030308 No Department of Fisheries, faculty of Natural Resources, University of Zabol, Zabol, Iran M. Miri Mirimohadeseh@uoz.ac.ir 100319475328460030309 100319475328460030309 No Hamoun International Wetland Research Institute, University of Zabol, Zabol, Iran M. Rigi mahin.rigi@uoz.ac.ir 100319475328460030310 100319475328460030310 No Hamoun International Wetland Research Institute, University of Zabol, Zabol, Iran