en aquaculture aquaculture پژوهشي Orginal research papers <span style="font-size:11pt"><span style="line-height:120%"><span style="font-family:Calibri,sans-serif"><span lang="TR" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">This study was conducted to compare the effectiveness of Ovaprim<b>^&trade;</b> and Ovapass<b>^&trade;</b> hormones to induce spawning in <i>Schizothorax zarudnyi</i>. The female (<a name="_Hlk133710340">n=48; 1535.12&plusmn;180.09 g</a>) and male broodstocks (n=53; 752.00&plusmn;48.30 g) were randomLy allocated in 4 experimental groups including T1: females which received 0.2, 0.5 and 0.5 mL /kg body weight (BW) Ovaprim with 24-h time intervals, T2:</span></span></span></span> <span lang="TR" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">females which treated with 0.5 and 0.5 mL <a name="_Hlk125334594">/kg </a>BW Ovapass with 12-h time intervals, T3: females were injected with 0.2, <a name="_Hlk125335180">0.5 and 0.5 mL /kg BW Ovapass with 24-h time intervals</a>, and T4: females were injected with a combination of Ovaprim (0.2 mL/kg) and Ovapass (0.5 and 0.5 mL/kg BW) with 24-h time intervals. The amount of injection in the first stage was 10%, the second stage was 90%, and the male fish were simultaneously injected with the second stage of the females at 0.3 mL/kg. The results showed that the highest rate of fertilization was detected in treatments 2 and 4 (93.33% and 92.33%, respectively), which had a significant difference with other groups (<i>p</i><0.05). No significant differences were observed between the treatments in the indices of relative and working fecundity and dry egg diameter (<i>p</i>>0.05). The lowest and highest latency period was observed in treatments 2 (27.33&plusmn; 0.66 h) and 1 (36.20&plusmn;3.77 h), respectively (<i>p</i><0.05). The results of this study clearly suggested that the Iranian Ovapass hormone is highly effective for <i>S. zarudnyi</i> reproduction and might be successfully replace with Ovaprim.</span></span></span></span><span dir="RTL" lang="AR-SA" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black"></span></span></span></span></span></span></span> Schizothorax zarudnyi, Artificial reproduction, Ovaprim, Ovapass, Fertilization 643 657 http://jifro.ir/browse.php?a_code=A-10-136-4&slc_lang=en&sid=1 B. Mohammadi Avizi arshadi.ali@gmail.com 100319475328460049035 100319475328460049035 No Department of Fisheries, Faculty of Natural Resources, University of Zabol, Zabol, Iran. A. Arshadi arshadi@uoz.ac.ir 100319475328460049036 100319475328460049036 Yes Department of Fisheries, Faculty of Natural Resources, University of Zabol, Zabol, Iran. A. Rahdari rahdari67@gmail.com 100319475328460049037 100319475328460049037 No Department of Aquatic Sciences, Hamoun International Wetland Institute, Research Institute of Zabol, Zabol, Iran.