en aquaculture aquaculture پژوهشي Orginal research papers <span style="font-size:11pt"><span style="line-height:120%"><span sans-serif="" style="font-family:Calibri,"><span style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">Regarding to the roles of prebiotics and probiotics in feeding the aquatic animals, the aim of this study was to evaluate the effects of <i>Pediococcus acidilactici</i>, Mannan-oligosaccharide prebiotic and Beta-glucan on hematologic and immunologic parameters of the trout. 720 healthy rainbow trout were divided into four groups as the control group and groups treating with prebiotics, probiotics and both. After the treatment, immunologic, hematologic, growth-nutritional parameters were measured with various stressors indicating the positive effects of simultaneous probiotic and prebiotic treatment on all above-mentioned parameters and stress prevention in the trout. </span></span></span></span></span></span></span> Trout, Pediococcus Acidilacitc, Mannan-oligosaccharide and beta-glucan, Hematology, Immunology 278 302 http://jifro.ir/browse.php?a_code=A-10-2541-1&slc_lang=en&sid=1 M.H. Nakhei Rad nakhaeirad_hadi@yahoo.com 100319475328460047742 100319475328460047742 No Aquatic Animal Health and Diseases PhD candidate, College of Veterinary Medicine, Islamic Azad University Science and Research Branch, Tehran, Iran A. Haghighi Khiabanian ASl gpathologist@gmail.com 100319475328460047743 100319475328460047743 Yes Assistant professor, Department of aquatic animal health and diseases, College of Veterinary Medicine, Islamic Azad University Science and Research Branch, Tehran, Iran Gh. Azari Takami gh-azari@srbiau.ac.ir 100319475328460047744 100319475328460047744 No Full professor, Department of aquatic animal health and diseases, College of Veterinary Medicine, Islamic Azad University Science and Research Branch, Tehran, Iran V. Razavilar vrazavi@ut.ac.ir 100319475328460047745 100319475328460047745 No Full professor, Department of aquatic animal health and diseases, College of Veterinary Medicine, Islamic Azad University Science and Research Branch, Tehran, Iran M. Tehrani Sharif maysamtehrani@yahoo.com 100319475328460047746 100319475328460047746 No Department of Clinical Pathology, College of Veterinary Medicine, Islamic Azad University Garmsar Branch, Garmsar, Iran