en aquaculture aquaculture پژوهشي Orginal research papers <font face="Times New Roman" size="3"> </font><p class="MsoNormal" style="margin: 0cm 0cm 0pt text-align: justify line-height: 120% text-justify: kashida text-kashida: 0%"><font size="3"><font face="Times New Roman"><span style="line-height: 120% mso-bidi-font-size: 12.0pt">A 6-week feeding experiments were carried out to determine the effects of different levels of dietary betaine on growth performance, food efficiency and survival rate of pike perch which has a critical period during transition feeding. Fingerlings of pike perch were fed with live food (treatment A), without betaine added to biomar (treatment B), 1% betaine added to biomar (treatment C) and 2% betaine added to biomar (treatment D) in 1000 l concreted tanks. 200 fingerlings (1.50 g, mean weight) were stocked in each tank and fed up to 7 meals per day. Higher increment in body weight (4.99 </span><span style="line-height: 120% mso-bidi-font-family: "Times New Roman" mso-bidi-font-size: 12.0pt">±</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt"> 0.73 g), specific growth rate (3.90 </span><span style="line-height: 120% mso-bidi-font-family: "Times New Roman" mso-bidi-font-size: 12.0pt">±</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt"> 0.06) and food efficiency (104.42 </span><span style="line-height: 120% mso-bidi-font-family: "Times New Roman" mso-bidi-font-size: 12.0pt">±</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt"> 4.27) were obtained with treatment D (2% betaine added to biomar). This treatment also showed significant (P<0.05) decrease in food conversion ratio (0.93 </span><span style="line-height: 120% mso-bidi-font-family: "Times New Roman" mso-bidi-font-size: 12.0pt">±</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt"> 0.04) in comparison with other treatments. Highest survival rate was observed in treatment B (biomar without betaine) with a 34.5 % rate and greatest cannibalism (1.03 </span><span style="line-height: 120% mso-bidi-font-family: "Times New Roman" mso-bidi-font-size: 12.0pt">±</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt"> 0.01) was found in treatment D, respectively. It was concluded that betaine could increase the palatability and acceptability of food and could be suitable to weaning the pike perch fingerlings to artificial diet. <o:p /></span></font></font></p><font face="Times New Roman" size="3"> </font> Sander lucioperca, Betaine, Food attractants, Growth, Food efficiency 902 910 http://jifro.ir/browse.php?a_code=A-10-1-208&slc_lang=en&sid=1 E. Zakipour Rahimabadi e_zakipour@yahoo.com 10031947532846004773 10031947532846004773 Yes M. Akbari 10031947532846004774 10031947532846004774 No A. Arshadi 10031947532846004775 10031947532846004775 No E Effatpanah 10031947532846004776 10031947532846004776 No